Search

Purpose: The disease course of chronic lymphocytic leukemia (CLL) varies significantly within cytogenetic groups. We hypothesized that high-resolution genomic analysis of CLL would identify additional recurrent abnormalities associated with short time-to-first therapy (TTFT).Experimental Design: We undertook high-resolution genomic analysis of 161 prospectively enrolled CLLs using Affymetrix 6.0 SNP arrays, and integrated analysis of this data set with gene expression profiles.Results: Copy number analysis (CNA) of nonprogressive CLL reveals a stable genotype, with a median of only 1 somatic CNA per sample. Progressive CLL with 13q deletion was associated with additional somatic CNAs, and a greater number of CNAs was predictive of TTFT. We identified other recurrent CNAs associated with short TTFT: 8q24 amplification focused on the cancer susceptibility locus near MYC in 3.7%; 3q26 amplifications focused on PIK3CA in 5.6%; and 8p deletions in 5% of patients. Sequencing of MYC further identified somatic mutations in two CLLs. We determined which catalytic subunits of phosphoinositide 3-kinase (PI3K) were in active complex with the p85 regulatory subunit and showed enrichment for the α subunit in three CLLs carrying PIK3CA amplification.Conclusions: Our findings implicate amplifications of 3q26 focused on PIK3CA and 8q24 focused on MYC in CLL. Clin Cancer Res; 18(14); 3791–802. ©2012 AACR.

XLS file, 1603KB.

PDF file, 449KB.

Improved biomarkers are needed to guide the optimal use of autologous stem cell transplantation (ASCT) for patients with relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL). We hypothesized that minimal residual disease (MRD) identified using immunoglobulin high-throughput sequencing in apheresis stem cell (ASC) samples or post-ASCT peripheral blood mononuclear cell (PBMC) and plasma samples could predict relapse. We studied 159 patients with R/R DLBCL who underwent ASCT, of whom 98 had an ASC sample and 60 had post-ASCT surveillance samples. After a median post-ASCT follow-up of 60 months, the 5-year progression-free survival (PFS) was 48%. MRD was detected in 23/98 (23%) ASC samples and was associated with very poor PFS (5-year PFS 13% vs 53%, p

The addition of high-dose cytarabine to rituximab/bendamustine (RB) induction could improve outcomes for transplant-eligible patients with mantle cell lymphoma (MCL). We conducted a pooled analysis of 2 phase 2 trials and an off-trial cohort each testing 3 cycles of RB and 3 cycles of rituximab/high-dose cytarabine (RC) followed by autologous stem cell transplantation (ASCT) among untreated, transplant-eligible patients with MCL. Dana-Farber Cancer Institute (DFCI) and Washington University in St. Louis (WUSTL) led separate phase 2 trials testing sequential and alternating cycles of RB/RC, respectively. Patients treated at DFCI with sequential RB/RC off trial were retrospectively identified. Minimal residual disease (MRD) was assessed in the DFCI trial. A total of 88 patients (23 DFCI trial, 18 WUSTL trial, and 47 off trial) received RB/RC; 92% of patients completed induction, and 84% underwent planned consolidative ASCT. Grade 3 or 4 adverse events among trial patients included lymphopenia (88%), thrombocytopenia (85%), neutropenia (83%), and febrile neutropenia (15%). There were no treatment-related deaths during induction and 2 following ASCT. Among 87 response-evaluable patients, the end-of-induction overall and complete response rates were 97% and 90%, respectively. After a median follow-up of 33 months, 3-year progression-free survival and overall survival were 83% and 92%, respectively. Patients undergoing MRD testing experienced prolonged MRD negativity after ASCT with emergence of MRD occurring in only 1 patient who subsequently relapsed. RB/RC followed by ASCT achieves high rates of durable remissions in transplant-eligible patients with MCL. These trials were registered at www.clinicaltrials.gov as #NCT01661881 (DFCI trial) and #NCT02728531 (WUSTL trial).

Disease relapse remains the leading cause of failure after autologous stem cell transplantation (ASCT) for patients with relapsed/refractory diffuse large B-cell lymphoma (R/R DLBCL). We conducted a phase 2, multicenter, single-arm study of the anti–PD-1 monoclonal antibody pembrolizumab given after ASCT in patients with chemosensitive DLBCL, hypothesizing that it would improve the progression-free survival (PFS) at 18 months after ASCT (primary endpoint) from 60% to 80%. Pembrolizumab was administered at 200 mg IV every 3 weeks for up to 8 cycles, starting within 21 days of post-ASCT discharge. Twenty-nine patients were treated on this study; 62% completed all 8 cycles. Seventy-nine percent of patients experienced at least one grade 3 or higher adverse event, and 34% experienced at least one grade 2 or higher immune-related adverse event. Overall, 59% of patients were alive and progression free at 18 months, which did not meet the primary endpoint. The 18-month overall survival was 93%. In conclusion, pembrolizumab was successfully administered as post-ASCT consolidation in patients with R/R DLBCL, but the PFS did not meet the protocol-specific primary objective and therefore does not support a larger confirmatory study. This trial was registered at www.clinicaltrials.gov as #NCT02362997.

Disease overview Follicular lymphoma (FL) is generally an indolent B cell lymphoproliferative disorder of transformed follicular center B cells. Follicular lymphoma is characterized by diffuse lymphadenopathy, bone marrow involvement, and splenomegaly. Extranodal involvement is less common. Cytopenias are relatively common but constitutional symptoms of fever, night sweats, and weight loss are uncommon in the absence of transformation to diffuse large B cell lymphoma. Diagnosis The diagnosis is based on histology from a biopsy of a lymph node or other affected tissue. Incisional biopsy is preferred over needle biopsies in order to give adequate tissue to assign grade and assess for transformation. Immunohistochemical staining is positive in virtually all cases for cell surface CD19, CD20, CD10 and monoclonal immunoglobulin, as well as cytoplasmic expression of bcl-2 protein. The overwhelming majority of cases have the characteristic t(14;18) translocation involving the IgH/bcl-2 genes. Risk stratification The Follicular Lymphoma International Prognostic Index (FLIPI) uses five independent predictors of inferior survival: age > 60 years, hemoglobin normal, Ann Arbor stage III/IV, number of involved nodal areas >4. The presence of 0-1, 2, and ≥ 3 adverse factors defines low, intermediate, and high-risk disease. There are other clinical prognostic models but the FLIPI remains the most common. Other factors such as time to relapse of less than 2 years from chemoimmunotherapy and specific gene mutations may also be useful for prognosis. Regardless of the prognostic model used, modern therapies have demonstrably improved prognosis. Risk-adapted therapy Observation continues to be appropriate for asymptomatic patients with low bulk disease and no cytopenias. There is no overall survival advantage for early treatment with either chemotherapy or single agent rituximab. For patients needing therapy, most patients are treated with chemoimmunotherapy, which has improved response rates, duration of response and overall survival (OS). Randomized studies have shown additional benefit for maintenance rituximab. Lenalidomide was non-inferior to chemoimmunotherapy in a randomized front-line study and, when combined with rituximab, was superior to rituximab alone in relapsed FL. Kinase inhibitors, other immunotherapies, and stem cell transplantation (SCT) are also considered for recurrent disease.

PI3 kinase (PI3K) activity is critical for survival of neoplastic B cells in patients with chronic lymphocytic leukemia (CLL). Blockade of PI3K signaling with idelalisib is effective for the treatment of relapsed CLL in combination with the anti-CD20 antibody ofatumumab. In this single-arm, open-label, nonrandomized phase 2 study, we investigated the efficacy and safety of idelalisib with ofatumumab in 27 patients with treatment-naïve CLL in need of therapy. Patients were planned to receive idelalisib for 2 monthly cycles, then idelalisib and ofatumumab for 6 cycles, followed by idelalisib indefinitely. The study was closed early and all patients ceased therapy when an increased rate of death as a result of infection was observed on other first-line idelalisib trials. Median time on therapy was 8.1 months, and median duration of follow-up was 39.7 months. We previously reported high rates of hepatotoxicity in a smaller cohort of patients in this trial; toxicities necessitated therapy discontinuation in 15 patients after a median of 7.7 months. The most frequent grade ≥3 adverse events were transaminitis (52% of patients), neutropenia (33%), and colitis/diarrhea (15%). The best overall response rate (ORR) was 88.9%, including 1 complete response. Median progression-free survival (PFS) was 23 months (95% confidence interval [CI], 18-36 months); 11 patients have not yet required second-line therapy. Idelalisib and ofatumumab demonstrated an unacceptable safety profile in the first-line setting, which resulted in a short PFS despite a high ORR. Future development of PI3K inhibitors for use in treatment-naïve CLL will require novel approaches to mitigate toxicities. This trial was registered at www.clinicaltrials.gov as #NCT02135133.

Background Bendamustine is a potent chemotherapy agent increasingly used to treat indolent non-Hodgkin lymphoma (iNHL). While effective, it causes significant T-cell lymphopenia, which may increase risk of infection. We examined infectious complications associated with bendamustine-containing regimens among older patients with iNHL. Methods For this Surveillance, Epidemiology, and End Results (SEER)-Medicare cohort study, we identified 9395 patients with iNHL (follicular, marginal zone, Waldenstrom macroglobulinemia) treated with chemotherapy from 2006 to 2013. Thirteen percent received bendamustine-containing regimens. We compared baseline characteristics and infection incidence rates between patients treated with and without bendamustine. We conducted multivariate Cox proportional hazards regression (adjusting for demographics, comorbidities, disease and treatment characteristics, risk factors for infection, and antimicrobial prophylaxis) to determine infectious risks associated with bendamustine. Results Bendamustine was associated with an increased risk of both common infections such as bacterial pneumonia (hazard ratio [HR], 1.50 [95% confidence interval {CI}, 1.21-4.85]) and opportunistic infections such as cytomegalovirus (HR, 3.98 [95% CI, 1.40-11.26]), varicella zoster virus (HR, 1.49 [95% CI, 1.18-1.89]), histoplasmosis (HR, 3.55 [95% CI, 1.10-11.42]), and Pneumocystis jirovecii pneumonia (when administered as third-line therapy: HR, 3.32 [95% CI, 1.00-11.11]). Risk of infections was more prominent in patients receiving bendamustine as part of later (third-line and above) regimens, and independently associated with well-established factors such as neutropenia and corticosteroid exposure. Conclusions Bendamustine is associated with an increased risk of common and opportunistic infections in patients with iNHL. Further prospective investigation into the potential role of antimicrobial prophylaxis is needed in these patients.

Summary Background CD37 is expressed on B-cell lymphoid malignancies, thus making it an attractive candidate for targeted therapy in non-Hodgkin lymphoma (NHL). IMGN529 is an antibody-drug conjugate comprising a CD37-binding antibody linked to the maytansinoid DM1, a potent anti-mitotic agent. Methods This first-in-human, phase 1 trial recruited adult patients with relapsed or refractory B-cell NHL. The primary objective was to determine the maximum tolerated dose (MTD) and recommended phase 2 dose. Secondary objectives were to evaluate safety, pharmacokinetics, and preliminary clinical activity. IMGN529 was administered intravenously once every 3 weeks, and dosed using a conventional 3 + 3 dose-escalation design. Results Forty-nine patients were treated at doses escalating from 0.1 to 1.8 mg/kg. Dose limiting toxicities occurred in eight patients and included peripheral neuropathy, febrile neutropenia, neutropenia, and thrombocytopenia. The most frequent treatment-emergent adverse events were fatigue (39%), neutropenia, pyrexia, and thrombocytopenia (each 37%). Adverse events led to treatment discontinuation in 10 patients (20%). Eight patients (16%) had treatment-related serious adverse events, the most common being grade 3 febrile neutropenia. The MTD (with growth factor support) was 1.4 mg/kg every 3 weeks. IMGN529 plasma exposure increased monotonically with dose and was consistent with target-mediated drug disposition. Five (13%) of 39 response-evaluable patients achieved an objective response (one complete response and four partial responses), four of which occurred in the subgroup of patients with diffuse large B-cell lymphoma. Conclusions The manageable safety profile of IMGN529 and preliminary evidence of activity, particularly in DLBCL patients, support the continued development of this novel CD37-targeting agent. Electronic supplementary material The online version of this article (10.1007/s10637-018-0570-4) contains supplementary material, which is available to authorized users.

Disease overview Follicular lymphoma is generally an indolent B cell lymphoproliferative disorder of transformed follicular center B cells. Follicular lymphoma (FL) is characterized by diffuse lymphadenopathy, bone marrow involvement, splenomegaly and less commonly other extranodal sites of involvement. In general, cytopenias can occur but constitutional symptoms of fever, nightsweats, and weight loss are uncommon. Diagnosis Diagnosis is based on histology of preferably a biopsy of a lymph node. Immunohistochemical staining is positive in virtually all cases for cell surface CD19, CD20, CD10, and monoclonal immunoglobulin, as well as cytoplasmic expression of bcl-2 protein. The overwhelming majority of cases have the characteristic t(14;18) translocation involving the IgH/bcl-2 genes. Risk stratification The Follicular Lymphoma International Prognostic Index prognostic model for FL uses five independent predictors of inferior survival: age >60 years, hemoglobin normal, Ann Arbor stage III/IV, number of involved nodal areas > 4. The presence of 0, 1, 2, and ≥ 3 adverse factors defines low, intermediate, and high-risk disease. With the use of more modern therapies, outcomes have improved. Risk-adapted therapy Observation continues to be adequate for asymptomatic patients with low bulk disease and no cytopenias, with no survival advantage for early treatment with either chemotherapy or rituximab alone. For patients needing therapy, most patients are treated with chemotherapy plus rituximab, which has improved response rates, duration of response and overall survival. Randomized studies have shown additional benefit for maintenance rituximab both following chemotherapy-rituximab and single agent rituximab. Experimental therapies as well as stem cell transplantation (SCT) are considered for recurrent disease.

Background: Autologous stem cell transplantation (ASCT) can be curative for a subset of patients (pts) with relapsed/refractory classical Hodgkin lymphoma (cHL). Post-ASCT maintenance therapy with brentuximab vedotin (BV) improves progression-free survival (PFS) among pts with high-risk clinical features, and PD-1 blockade is also being investigated in this setting. Ideally, novel biomarkers could be used to guide pt selection for these post-ASCT therapies. We hypothesized that the presence of minimal residual disease (MRD), quantified using immunoglobulin-based next generation sequencing (IgNGS), could predict post-ASCT relapse. As a preliminary test of this hypothesis, we analyzed a cohort of cHL pts who had serial peripheral blood mononuclear cell (PBMC) and plasma samples collected before or after ASCT. Methods: Samples from 2 cohorts (n=36) were analyzed. 28 pts were prospectively enrolled on a biobanking protocol and underwent ASCT at Dana-Farber Cancer Institute between 2014-2016 (biobank cohort). In addition, 8 pts underwent ASCT between 2015 and 2016 and subsequently participated in a multicenter phase II trial of post-ASCT pembrolizumab maintenance (PM) (trial cohort) (Armand, Blood 2020). Tumor tissue and serial post-ASCT plasma and PBMC samples were collected for all pts, and some pts also had pre-ASCT PB samples available for analysis. NGS of Ig receptor sequences (IgNGS) (clonoSEQ Ò, Adaptive Biotechnologies) was used to identify and track tumor clonotypes, as previously described (Ching, BMC Cancer 2020). MRD testing was not used for clinical decision making. Results: The 36 enrolled pts received a median of 2 lines of therapy, and 30 pts (83%) achieved a complete response (CR) on pre-ASCT positron emission tomography (PET). In total, 19 pts received post-ASCT treatment - PM (n=8, all on trial), radiation therapy (n=5), BV maintenance (n=4), and allogeneic stem cell transplantation as part of a planned tandem transplant (n=2). Among 36 enrolled pts, 12 (33%) had an identifiable clonotype (11/28 biobank and 1/8 trial). Higher rates of clonotype detection were seen in pts aged The 12 clonotyped pts had a median of 4 (range 1-13) post-ASCT plasma and 3 (range 1-17) post-ASCT PBMC samples. Among the 4 pts who relapsed, 3 had MRD detected within plasma samples with lead times of 0, 11, and 909 days (Figure 1). The pembrolizumab trial pt had detectable MRD early after ASCT which cleared within 9 weeks of starting pembrolizumab therapy, remained undetectable for the duration of pembrolizumab treatment, and became detectable again 5 months after completing PM in conjunction with clinical relapse. All pts with detectable MRD in a post-ASCT plasma sample subsequently relapsed (100% specificity). One pt relapsed without detectable MRD, but had a long interval (312 days) from last plasma sample to relapse. IgNGS testing from PBMC samples did not correlate with clinical outcomes; only two PBMC samples had detectable MRD and both were from a pt who did not relapse. 3 pts had pre-ASCT plasma samples collected concurrently with post-salvage PET scans. One pt achieved a partial response (PR) after 2 cycles of bendamustine and BV (Benda-BV), progressive disease after 4 cycles of Benda-BV, and a CR after pembrolizumab. MRD was detected after two cycles of Benda-BV (6.52 counts per million), was rising after 4 cycles of benda-BV (8.99 counts per million) and was undetectable after pembrolizumab. The pt remains in remission after a tandem transplant. Pre-ASCT samples were MRD negative in two other pts (1 CR, 1 PR) following salvage chemotherapy, both of whom remain in remission after ASCT. Conclusions: The clonotype detection rate among pts with cHL was considerably lower than has been reported for other B-cell lymphomas, likely due to the scarcity of Reed Sternberg cells within cHL tumor samples. Novel MRD techniques for cHL should be investigated. In this pilot study, among pts with a detectable clonotype, MRD was a dynamic marker of response to different therapies and was a specific indicator of impending relapse, suggesting that additional studies of MRD in cHL are warranted. Figure 1 Figure 1. Disclosures Brown: Gilead, Loxo/Lilly, SecuraBio, Sun, TG Therapeutics: Research Funding; Invectys: Other: Data Safety Monitoring Committee Service; Abbvie, Acerta/Astra-Zeneca, Beigene, Bristol-Myers Squibb/Juno/Celgene, Catapult, Eli Lilly, Genentech/Roche, Janssen, MEI Pharma, Morphosys AG, Nextcea, Novartis, Pfizer, Rigel: Consultancy. Crombie: Roche: Research Funding; Incyte: Consultancy; Karyopharm: Consultancy; Merck: Research Funding; Abbvie: Research Funding; Bayer: Research Funding. Davids: TG Therapeutics: Consultancy, Research Funding; Verastem: Consultancy, Research Funding; Takeda: Consultancy; Surface Oncology: Research Funding; AbbVie: Consultancy; Genentech: Consultancy, Research Funding; BMS: Consultancy, Research Funding; Astra-Zeneca: Consultancy, Research Funding; MEI Pharma: Consultancy, Research Funding; Ascentage Pharma: Consultancy, Research Funding; Novartis: Consultancy, Research Funding; Pharmacyclics: Consultancy, Research Funding; Adaptive Biotechnologies: Consultancy; BeiGene: Consultancy; Celgene: Consultancy; Eli Lilly and Company: Consultancy; Janssen: Consultancy; MEI Pharma: Consultancy; Merck: Consultancy; Research to Practice: Consultancy. Jacobsen: Takeda: Consultancy; Syros: Consultancy; Janssen: Research Funding; Novartis: Research Funding; Pharmacyclics: Research Funding; Acerta: Research Funding. Jacobson: Lonza: Consultancy, Honoraria, Other: Travel support; Precision Biosciences: Consultancy, Honoraria, Other: Travel support; Kite, a Gilead Company: Consultancy, Honoraria, Other: Travel support; Axis: Speakers Bureau; Clinical Care Options: Speakers Bureau; Nkarta: Consultancy, Honoraria; Novartis Pharmaceuticals Corporation: Consultancy, Honoraria, Other: Travel support; Pfizer: Consultancy, Honoraria, Other: Travel support, Research Funding; Humanigen: Consultancy, Honoraria, Other: Travel support; AbbVie: Consultancy, Honoraria; Celgene: Consultancy, Honoraria, Other: Travel support. LaCasce: Bristol-Myers Squibb Company.: Other: Data Safetly and Monitoring. Dahi: Kite / Gilead: Membership on an entity's Board of Directors or advisory committees. Chen: Gamida: Consultancy; Incyte: Consultancy. Herrera: ADC Therapeutics: Consultancy, Research Funding; Merck: Consultancy, Research Funding; Tubulis: Consultancy; Kite, a Gilead Company: Research Funding; Seagen: Consultancy, Research Funding; Takeda: Consultancy; Gilead Sciences: Research Funding; AstraZeneca: Consultancy, Research Funding; Karyopharm: Consultancy; Genentech: Consultancy, Research Funding; Bristol Myers Squibb: Consultancy, Research Funding. Armand: IGM: Research Funding; Tensha: Research Funding; Roche: Research Funding; Genentech: Consultancy, Research Funding; AstraZeneca: Consultancy; Regeneron: Consultancy; Epizyme: Consultancy; Enterome: Consultancy; Daiichi Sankyo: Consultancy; Miltenyi: Consultancy; Tessa Therapeutics: Consultancy; GenMab: Consultancy; C4: Consultancy; Kite: Research Funding; Pfizer: Consultancy; Infinity: Consultancy; Otsuka: Research Funding; Sigma Tau: Research Funding; Morphosys: Consultancy; Celgene: Consultancy; ADC Therapeutics: Consultancy; Adaptive: Consultancy, Research Funding; Affimed: Consultancy, Research Funding; BMS: Consultancy, Honoraria, Research Funding; Merck: Consultancy, Honoraria, Research Funding.

Purpose Double-hit lymphomas (DHLs) and double-expressor lymphomas (DELs) are subtypes of diffuse large B-cell lymphoma (DLBCL) associated with poor outcomes after standard chemoimmunotherapy. Data are limited regarding outcomes of patients with relapsed or refractory (rel/ref) DEL or DHL who undergo autologous stem-cell transplantation (ASCT). We retrospectively studied the prognostic impact of DEL and DHL status on ASCT outcomes in patients with rel/ref DLBCL. Methods Patients with chemotherapy-sensitive rel/ref DLBCL who underwent ASCT at two institutions and in whom archival tumor material was available were enrolled. Immunohistochemistry for MYC, BCL2, and BCL6 and fluorescence in situ hybridization (FISH) for MYC were performed. In cases with MYC rearrangement or copy gain, FISH for BCL2 and BCL6 was also performed. Results A total of 117 patients were included; 44% had DEL and 10% had DHL. DEL and DHL were associated with inferior progression-free survival (PFS), and DHL was associated with poorer overall survival (OS). The 4-year PFS in patients with DEL compared with those with non-DEL was 48% versus 59% ( P = .049), and the 4-year OS was 56% versus 67% ( P = .10); 4-year PFS in patients with DHL compared with those with non-DHL was 28% versus 57% ( P = .013), and 4-year OS was 25% versus 61% ( P = .002). The few patients with concurrent DEL and DHL had a poor outcome (4-year PFS, 0%). In multivariable models, DEL and DHL were independently associated with inferior PFS, whereas DHL and partial response ( v complete response) at transplant were associated with inferior OS. Conclusion DEL and DHL are both associated with inferior outcomes after ASCT in patients with rel/ref DLBCL. Although ASCT remains a potentially curative approach, these patients, particularly those with DHL, are a high-risk subset who should be targeted for investigational strategies other than standard ASCT.

Background: While most patients (pts) with follicular lymphoma (FL) have excellent outcomes with frontline chemoimmunotherapy (CIT), a subset of pts will experience early progression, which is associated with inferior survival. Earlier identification of high-risk FL pts could allow for intervention with novel treatments to forestall early progression. Current prognostic tools are imperfect, particularly for pts receiving bendamustine-based regimens, and novel biomarkers are needed. In Hodgkin lymphoma, interim positron emission tomography (iPET) evaluated based on Deauville score (DS) is highly prognostic and is used to guide response-adapted therapy. The prognostic value of iPET using DS has not yet been assessed in a large population of FL pts receiving frontline CIT. We hypothesized that iPET would predict progression-free survival (PFS) in this population which could support PET-guided treatment approaches. Methods: We retrospectively identified pts with a diagnosis of FL (grade 1-3B) who initiated frontline CIT at Dana-Farber Cancer Institute from 1/2005-3/2019 and underwent an iPET after 2-4 cycles of CIT. Pts who received radiation (XRT) prior to CIT were included. Baseline, interim, and (when available) end-of-treatment (EOT) PET scans were reviewed by a nuclear medicine radiologist in a blinded fashion and assigned a DS of 1-5. Results: 118 pts were identified. The median age was 55 (range 26-82). 73 pts (62%) had grade 1-2 FL, 17 pts (14%) grade 3A, 15 pts (13%) grade 3B, 12 pts (10%) grade 3 NOS, and 1 pt (1%) grade not reported. FLIPI score was low for 32%, intermediate for 42% and high for 26%. In total, 5 pts (4%) received XRT before CIT. The most common CIT regimens were RCHOP (54%) and BR (42%) (Table 1). 107 pts (91%) received 6 cycles of CIT and 4 pts (3%) received 8 cycles, while 7 pts (6%) discontinued CIT after 4-5 cycles due to cytopenias (4), heart failure (1), infection (1), or pt decision (1). 88% of iPETs were performed after 3 cycles. iPET DS was 1 for 18%, 2 for 57%, 3 for 13%, 4 for 9%, and 5 for 3%. EOT PET was available for review for 112 pts (95%) and demonstrated DS of 1 for 32%, 2 for 56%, 3 for 3%, 4 for 4%, and 5 for 5%. After CIT, 29 pts (25%) received a median of 9 doses (range 1-13) of rituximab maintenance (RM) and 2 pts (2%) received consolidative XRT. With a median follow-up of 54 months (range 5-186), the 4-year (yr) PFS and overall survival (OS) for the entire cohort were 69% (95% CI 58-77%) and 94% (95% CI 87-98%), respectively. iPET was a significant predictor of PFS (p=0.0011 for 5 categories). Compared to pts with an iPET DS of 1-2, pts with a DS of 3 (HR 3.0, p=0.006) or a DS of 4-5 (HR 3.4, p=0.004) had inferior PFS (Figure 1) and were grouped together in a +iPET group (n=30) for all analyses. The 4-yr PFS for DS 1-2 and DS 3-5 pts were 77% and 46%, respectively (HR 3.2, p EOT PET was also a significant predictor of PFS (p Conclusions: Our study suggests that iPET may be a useful prognostic marker in FL. Additionally, iPET interpretation may be different in FL compared to other lymphomas. In this cohort, pts with a DS of 3 on iPET had inferior PFS with outcomes similar to those of pts with a DS of 4-5. A DS of 3-5 on iPET appears to predict earlier progression independent of EOT PET while providing response-driven prognostic information earlier in a patient's treatment course. If validated, these results suggest that iPET could be investigated as a tool for response-adapted treatment strategies in FL. Disclosures Salles: BMS/Celgene: Honoraria, Other: consultancy or advisory role; Kite, a Gilead Company: Honoraria, Other: consultancy or advisory role ; Epizyme: Honoraria, Other: consultancy or advisory role; Janssen: Honoraria, Other: consultancy or advisory role; MorphoSys: Honoraria, Other: consultancy or advisory role; Novartis: Honoraria, Other: consultancy or advisory role; Roche: Honoraria, Other: consultancy or advisory role; Abbvie: Other: consultancy or advisory role; Autolos: Other: consultancy or advisory role; Debiopharm: Consultancy, Honoraria, Other: consultancy or advisory role; Genmab: Honoraria, Other; Karyopharm: Honoraria; Takeda: Honoraria. Zelenetz:MEI Pharma: Research Funding; Celgene: Research Funding; Sandoz: Research Funding; Novartis: Consultancy; Gilead: Research Funding; Celgene: Consultancy; BeiGene: Membership on an entity's Board of Directors or advisory committees; Adaptive Biotechnology: Consultancy; MorphoSys: Research Funding; Gilead: Consultancy; Genentech/Roche: Consultancy; Amgen: Consultancy; Janssen: Consultancy; Roche: Research Funding. Brown:Janssen, Teva: Speakers Bureau; Gilead, Loxo, Sun, Verastem: Research Funding; Abbvie, Acerta, AstraZeneca, Beigene, Invectys, Juno/Celgene, Kite, Morphosys, Novartis, Octapharma, Pharmacyclics, Sunesis, TG Therapeutics, Verastem: Consultancy. Crombie:AbbVie: Research Funding; Bayer: Research Funding. Davids:Ascentage Pharma: Consultancy, Research Funding; AstraZeneca: Consultancy, Research Funding; BeiGene: Consultancy; Celgene: Consultancy; Eli Lilly: Consultancy; AbbVie: Consultancy; Adaptive Biotechnologies: Consultancy; Genentech: Consultancy, Research Funding; Janssen: Consultancy; Bristol Myers Squibb: Research Funding; Merck: Consultancy; Research to Practice: Honoraria; Syros Pharmaceuticals: Consultancy; Zentalis: Consultancy; Sunesis: Consultancy; Gilead Sciences: Consultancy; Novartis: Consultancy, Research Funding; MEI Pharma: Consultancy, Research Funding; Surface Oncology: Research Funding; Pharmacyclics: Consultancy, Research Funding; TG Therapeutics: Consultancy, Research Funding; Verastem: Consultancy, Research Funding. Fisher:Kyowa Kirin: Membership on an entity's Board of Directors or advisory committees. Jacobsen:Merck: Consultancy; Acerta: Consultancy; Astra-Zeneca: Consultancy; Pharmacyclics: Research Funding; F. Hoffmann-LaRoche: Research Funding; Novartis: Research Funding; Takeda: Honoraria. LaCasce:BMS: Consultancy; Research to Practice: Speakers Bureau; UptoDate: Patents & Royalties. Armand:Sigma Tau: Research Funding; Tensha: Research Funding; Pfizer: Consultancy; Affimed: Consultancy, Research Funding; IGM: Research Funding; Adaptive: Consultancy, Research Funding; Celgene: Consultancy; Merck & Co., Inc.: Consultancy, Honoraria, Research Funding; Otsuka: Research Funding; Bristol-Myers Squibb: Consultancy, Honoraria, Research Funding; Roche: Research Funding; Infinity: Consultancy; ADC Therapeutics: Consultancy; Genentech: Research Funding.

Background: While autologous stem cell transplantation (ASCT) can be curative for patients (pts) with relapsed or refractory diffuse large B-cell lymphoma (DLBCL), relapse remains common. With the emergence of novel effective therapies, it is even more important to identify pts at high risk of treatment failure who may not benefit from ASCT, and pts with impending post-ASCT relapse who may be candidates for pre-emptive interventions. We assembled cohorts of DLBCL pts who underwent ASCT and had apheresis stem cell (ASC) samples or serially collected post-ASCT peripheral blood mononuclear cell (PBMC) and plasma samples. We hypothesized that circulating tumor DNA (ctDNA) identified using immunoglobulin-based next generation sequencing (IgNGS) in ASC or PB samples could predict relapse. Methods: Samples from 3 cohorts were analyzed. Pts in cohort 1 (C1) underwent ASCT at Dana-Farber Cancer Institute (DFCI) from 2003-2013 (Herrera, ASH 2015). Archival tumor tissue and ASC samples were retrospectively collected for analysis. Pts in cohort 2 (C2) were prospectively enrolled on a banking protocol at DFCI and underwent ASCT from 2014-2016. Pts in cohort 3 (C3) underwent ASCT from 2015-2016 and participated in a multicenter phase II trial of post-ASCT pembrolizumab maintenance (PM) (Frigault, Blood Adv 2020). Pts in C2/C3 had tumor tissue and serially collected post-ASCT PBMC and plasma samples as mandated by protocol, and a subset had available pre-ASCT PB or ASC samples. Because PM did not demonstrate a clear benefit in the trial, all cohorts were analyzed together. IgNGS (Adaptive Biotechnologies; Seattle, WA) was performed, as previously described (Armand, BJH 2013). In all cases, ctDNA testing was not performed in real-time or used to drive clinical decisions. Results: 152 pts were enrolled. Among 141 pts with sufficient DNA for testing, a clonotype was identified in 112 (78%) with a higher detection rate in more recent cohorts - C2 (93%) and C3 (90%) vs C1 (67%). Among 97 pts with an available ASC sample, 23 (24%) were ctDNA-positive (pos). With a median follow-up among survivors of 69 months (m) (range 13-185), the 5-year (y) progression-free survival (PFS) for ASC ctDNA-pos and ASC ctDNA-negative (neg) pts were 13% (95% CI 3-30%) and 52% (95% CI 40-63%), respectively (HR 2.8, p 56 pts had a median of 3 (range 1-8) post-ASCT plasma samples available for analysis. Within this cohort, 25 pts relapsed and 2 pts died in remission. 21 pts (38%) had detectable ctDNA in a median of 2 post-ASCT samples (range 1-5); among them, 18 (86%) relapsed with a median lead time from first ctDNA detection to relapse of 52 days (range 0-518). Among the 3 ctDNA-pos pts who did not relapse, 2 had detectable ctDNA at a single time point and subsequently became ctDNA-neg, and 1 developed acute myeloid leukemia and underwent allogeneic transplantation. Among 20 pts who relapsed and had ≥1 plasma sample available within 100 days of relapse, 18 (90%) had detectable ctDNA. PBMC testing had inferior performance characteristics (Table). Conclusions: Identification of ctDNA using IgNGS within an ASC sample is a powerful predictor of post-ASCT relapse and provides (at least in this cohort) a better way to predict relapse than pre-ASCT PET. Detection of ctDNA in pre-ASCT plasma also appears to be predictive of relapse. In ctDNA-pos pts, given the dismal PFS, strong consideration could be given to alternative treatment strategies, e.g. CAR-T cell therapy. Furthermore, detection of ctDNA in post-ASCT plasma samples is closely associated with impending relapse, which provides an attractive platform for pre-emptive therapeutic intervention. Figure Disclosures Brown: Dynamo Therapeutics: Consultancy; Morphosys: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other; Octapharma: Consultancy; Pfizer: Consultancy; Acerta: Consultancy; Sun: Research Funding; Genentech: Consultancy; Rigel Pharmaceuticals: Consultancy; Eli Lilly and Company: Consultancy; Juno/Celgene: Consultancy; Invectys: Membership on an entity's Board of Directors or advisory committees, Other: DSMC; Gilead: Consultancy, Research Funding; Astra-Zeneca: Consultancy; Janssen: Honoraria; Sunesis: Consultancy; Novartis: Consultancy; Loxo: Consultancy, Research Funding; Nextcea: Consultancy; MEI Pharma: Consultancy; Kite: Consultancy; Pharmacyclics: Consultancy; AbbVie: Consultancy; Catapult: Consultancy; BeiGene: Consultancy; Verastem: Consultancy, Research Funding; TG Therapeutics: Consultancy. Crombie:AbbVie: Research Funding; Bayer: Research Funding. Davids:Gilead Sciences: Consultancy; Zentalis: Consultancy; Sunesis: Consultancy; Syros Pharmaceuticals: Consultancy; Research to Practice: Honoraria; Merck: Consultancy; Bristol Myers Squibb: Research Funding; Janssen: Consultancy; Genentech: Consultancy, Research Funding; Eli Lilly: Consultancy; Celgene: Consultancy; AstraZeneca: Consultancy, Research Funding; BeiGene: Consultancy; Ascentage Pharma: Consultancy, Research Funding; Adaptive Biotechnologies: Consultancy; AbbVie: Consultancy; Novartis: Consultancy, Research Funding; Verastem: Consultancy, Research Funding; MEI Pharma: Consultancy, Research Funding; Surface Oncology: Research Funding; Pharmacyclics: Consultancy, Research Funding; TG Therapeutics: Consultancy, Research Funding. Fisher:Kyowa Kirin: Membership on an entity's Board of Directors or advisory committees. Jacobsen:Merck, Pharmacyclics, F. Hoffmann-LaRoche, Novartis: Research Funding; Takeda: Honoraria; Acerta, AstraZeneca, Merck: Consultancy. LaCasce:BMS: Consultancy; Research to Practice: Speakers Bureau; UptoDate: Patents & Royalties. Dahi:Kite: Consultancy. Nieto:Secura Bio: Other: Grant Support; Novartis: Other: Grant Support; Affimed: Consultancy, Other: Grant Support; Astra Zeneca: Other: Grant Support. Chen:Incyte Corporation: Consultancy; Takeda: Consultancy; Magenta: Consultancy; Kiadis: Consultancy; Actinium: Other: Data and Safety Monitoring Board Member; Equillium: Other: Data and Safety Monitoring Board Member; AbbVie: Other: Data and Safety Monitoring Board Member. Herrera:Pharmacyclics: Research Funding; Bristol Myers Squibb: Consultancy, Other: Travel, Accomodations, Expenses, Research Funding; Karyopharm: Consultancy; Merck: Consultancy, Research Funding; Genentech, Inc./F. Hoffmann-La Roche Ltd: Consultancy, Research Funding; Gilead Sciences: Consultancy, Research Funding; Seattle Genetics: Consultancy, Research Funding; Immune Design: Research Funding; AstraZeneca: Research Funding. Armand:IGM: Research Funding; Bristol-Myers Squibb: Consultancy, Honoraria, Research Funding; Affimed: Consultancy, Research Funding; ADC Therapeutics: Consultancy; Celgene: Consultancy; Pfizer: Consultancy; Infinity: Consultancy; Otsuka: Research Funding; Genentech: Research Funding; Roche: Research Funding; Tensha: Research Funding; Merck: Consultancy, Honoraria, Research Funding; Adaptive: Consultancy, Research Funding; Sigma Tau: Research Funding.

Chemoimmunotherapy followed by autologous stem cell transplantation (ASCT) is a standard therapy for transplant-eligible patients with newly diagnosed mantle cell lymphoma (MCL). The achievement of complete remission (CR) and minimal residual disease (MRD) negativity are associated with better outcomes. We tested an induction regimen of rituximab/bendamustine followed by rituximab/high-dose cytarabine (RB/RC). This phase 2 study (NCT01661881) enrolled 23 transplant-eligible patients aged 42-69, of whom 70% were MCL international prognostic index low-risk. Patients received three cycles of RB followed by three cycles of RC. The primary endpoint of the trial was the rate of CR after six cycles of therapy, with a rate of 75% considered promising. 96% of patients achieved a CR/unconfirmed CR after treatment, meeting the primary objective. One patient progressed on study, one declined ASCT in CR, and the remaining 21 underwent successful stem cell collection and ASCT. After a median follow-up of 13 months, the progression-free survival rate was 96%. Among 15 MRD-evaluable patients who completed treatment, 93% achieved MRD negativity after RB/RC. In conclusion, RB/RC achieves very high CR and MRD negativity rates in transplant-eligible patients, with a favourable safety profile. RB/RC warrants further comparative studies, and may become a useful alternative to RCHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisone)-based induction regimens in this patient population.

Disease overview: Follicular lymphoma is generally an indolent B cell lymphoproliferative disorder of transformed follicular center B cells. Follicular lymphoma (FL) is characterized by diffuse lymphoadenopathy, bone marrow involvement, splenomegaly, and less commonly other extranodal sites of involvement. In general, cytopenias can occur but constitutional symptoms of fever, night sweats, and weight loss are uncommon. Diagnosis: Diagnosis is based on histology of preferably a biopsy of a lymph node. Immunohistochemical staining is positive in virtually all cases for cell surface CD19, CD20, CD10, and monoclonal immunoglobulin, as well as cytoplasmic expression of bcl-2 protein. The overwhelming majority of cases have the characteristic t(14;18) translocation involving the IgH/bcl-2 genes. Risk stratification: The Follicular Lymphoma International Prognostic Index prognostic model for FL uses five independent predictors of inferior survival: age >60 years, hemoglobin normal, Ann Arbor stage III/IV, number of involved nodal areas > 4. The presence of 0, 1, 2, and ≥ 3 adverse factors defines low, intermediate, and high-risk disease. With the use of more modern therapies, outcomes have improved. Risk-adapted therapy: Observation continues to be adequate for asymptomatic patients with low bulk disease and no cytopenias, with no survival advantage for early treatment with either chemotherapy or rituximab alone. For patients needing therapy, most patients are treated with chemotherapy plus rituximab, which has improved response rates, duration of response and overall survival. Randomized studies have shown additional benefit for maintenance rituximab both following chemotherapy-rituximab and single agent rituximab. Experimental therapies as well as stem cell transplantation (SCT) are considered for recurrent disease. Am. J. Hematol. 90:1172–1178, 2015. © 2015 Wiley Periodicals, Inc.

Purpose Clonal hematopoiesis of indeterminate potential (CHIP) is an age-related condition characterized by somatic mutations in the blood of otherwise healthy adults. We hypothesized that in patients undergoing autologous stem-cell transplantation (ASCT) for lymphoma, CHIP at the time of ASCT would be associated with an increased risk of myelodysplastic syndrome and acute myeloid leukemia, collectively termed therapy-related myeloid neoplasm (TMN), and other adverse outcomes. Methods We performed whole-exome sequencing on pre- and post-ASCT samples from 12 patients who developed TMN after autologous transplantation for Hodgkin lymphoma or non-Hodgkin lymphoma and targeted sequencing on cryopreserved aliquots of autologous stem-cell products from 401 patients who underwent ASCT for non-Hodgkin lymphoma between 2003 and 2010. We assessed the effect of CHIP at the time of ASCT on subsequent outcomes, including TMN, cause-specific mortality, and overall survival. Results For six of 12 patients in the exome sequencing cohort, mutations found in the TMN specimen were also detectable in the pre-ASCT specimen. In the targeted sequencing cohort, 120 patients (29.9%) had CHIP at the time of ASCT, which was associated with an increased rate of TMN (10-year cumulative incidence, 14.1% v 4.3% for those with and without CHIP, respectively; P = .002). Patients with CHIP had significantly inferior overall survival compared with those without CHIP (10-year overall survival, 30.4% v 60.9%, respectively; P < .001), including increased risk of death from TMN and cardiovascular disease. Conclusion In patients undergoing ASCT for lymphoma, CHIP at the time of transplantation is associated with inferior survival and increased risk of TMN.

There are no "benign lymphomas", a fact due to the nature of lymphoid cells to circulate and home as part of their normal function. Thus, benign clonal expansions of lymphocytes are only rarely recognized when localized. Recent studies have identified a number of lymphoid proliferations that lie at the interface between benign and malignant. Some of these are clonal proliferations that carry many of the molecular hallmarks of their malignant counterparts, such as BCL2/IGH and CCND1/IGH translocations associated with the in situ forms of follicular lymphoma and mantle cell lymphoma, respectively. There are other clonal B-cell proliferations with low risk of progression; these include the pediatric variants of follicular lymphoma and marginal zone lymphoma. Historically, early or incipient forms of T/NK-cell neoplasia also have been identified, such as lymphomatoid papulosis and refractory celiac disease. More recently an indolent form of T-cell lymphoproliferative disease affecting the gastrointestinal tract has been described. Usually, CD8(+), the clonal cells are confined to the mucosa. The clinical course is chronic, but non-progressive. NK-cell enteropathy is a clinically similar condition, composed of cytologically atypical NK-cells that may involve the stomach, small bowel or colon. Breast implant-associated anaplastic large cell lymphoma is a cytologically alarming lesion that is self-limited if confined to the seroma cavity. Atypical lymphoid proliferations that lie at the border of benign and malignant can serve as instructive models of lymphomagenesis. It is also critical that they be correctly diagnosed to avoid unnecessary and potentially harmful therapy.

In the article that accompanies this editorial, Casulo et al report an analysis of data from the National LymphoCare Study that demonstrates that patients with follicular lymphoma (FL) who relapse within 2 years of therapy with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone have a poor prognosis, independent of that predicted by the FL International Prognostic Index (FLIPI). This accounts for approximately 20% of patients with FL. Specifically, the 5-year overall survival (OS) in this group is only 50% compared with 90% for patients who have a longer treatment response. This corroborates an earlier analysis that was performed in the prerituximab era that identified older age and a response duration of 1 year or less as factors associated with a shortened survival. These analyses raise important questions regarding the biology of these lymphomas and approaches to their therapy. Specifically, what is the biologic and genetic make-up of these high-risk lymphomas, and should their treatment be tailored to these findings, as opposed to more traditional chemotherapeutic approaches? Several studies have correlated both circulating immune cells and immunologic components of the tumor microenvironment with prognosis in FL. An elevated absolute lymphocyte count at diagnosis ( 890-1,000 cells/ L) has been associated with longer time to progression and survival, independent of the FLIPI score, in both the prerituximab and rituximab eras (median OS, 14.6 v 6.1 years; P .001, before rituximab; median time to progression, 36.5 v 8.1 months, with rituximab). Conversely, an elevated absolute monocyte count has been associated with a poor prognosis, with a median progressionfree survival after several different rituximab-containing regimens of approximately 27 months versus not yet reached (P .001). Casulo et al review the findings of gene expression profiles of FL biopsies, which identify two major clusters of genes that correlate with prognosis. These clusters, named immune-response 1 (IR-1) and immuneresponse 2 (IR-2), were enriched for genes encoding certain T-cell markers and those expressed in macrophages, and genes expressed in macrophages and/or dendritic cells, respectively. IR-1 was associated with a decreased risk of death compared with IR-2 (risk ratio for death, 0.15 [95% CI, 0.05 to 0.46] v 9.35 [95% CI, 3.02 to 28.90]). Similarly, increased numbers of CD8 T cells in FL biopsies are associated with longer survival, whereas higher numbers of tumor-associated CD68 macrophages are associated with poor outcomes. These findings suggest that markers of immune response and inflammation are important determinants of prognosis in this disease. An antitumor adaptive immune response may lead to improved outcomes. However, increased numbers and activation of monocytes and macrophages, perhaps a result of tumor-induced inflammatory cytokines, lead to, among other things, the suppression of this important host antitumor immune response. Genetic evaluation of tumor cells in FL biopsies has yielded important information regarding the pathogenesis of this disease. Oligonucleotide arrays identified several genes, including cyclin B1, CDC2, CDKN3A, CKS1B, ANP32E, and KIAA0101, the expression of which was associated with improved outcomes. Deep sequencing analysis allows for the identification of recurrent somatic mutations in FL, and their incorporation into prognostic tools to determine a more biologically relevant, genetically annotated prognostic index. Mutations in epigenetic regulators including EZH2, CREBBP, EP300, and MLL2, and less frequently linker histone genes and ARID1A, transcriptions factor genes such as OCT2, IRF8, EBF1, and PAX5, and cell cycle regulatory genes like CDKN2A and TP53, have been described, with frequencies ranging from as high as 60% to 90% for MLL2 and CREBBP (suggesting that these are early driver mutations) to 5% to 10% for genes like ARID1A, IRF8, and OCT2. Understanding the interaction between the accumulation of these recurrent, somatic mutations and the biology and prognosis of follicular lymphoma will help to both distinguish patients expected to do poorly from those whose disease will have a long natural history, and to investigate differential therapeutic approaches tailored to the underlying genetic and biologic determinants of tumor growth and survival. If, in studying the immunologic and inflammatory host response to, and the genetic landscape of, these lymphomas, we are able to define this high-risk subgroup of patients with FL, the question becomes whether we could use this information to effectively treat these patients differently. Although high-dose chemotherapy and autologous stem-cell transplantation (HDC-ASCT) in first remission seems to have no effect on OS in all comers, results might be different for this cohort of high-risk patients. To study this would require an ability to identify these patients at diagnosis. Given that the efficacy of HDC-ASCT is maintained in the case of chemosensitive relapse, reserving HDC-ASCT for patients who relapse within the first 2 years of their initial therapy may be a more prudent strategy. However, it may be that this is a particularly chemoresistant population and that, instead, attention should be paid to targeting JOURNAL OF CLINICAL ONCOLOGY E D I T O R I A L VOLUME 33 NUMBER 23 AUGUST 1

This study assessed the safety and preliminary efficacy of escalated dose subcutaneous alemtuzumab in combination with rituximab in chronic lymphocytic leukemia. Twenty-eight patients with relapsed refractory chronic lymphocytic leukemia were treated on four dosing cohorts of weekly rituximab at 375 mg/m(2) and alemtuzumab doses that started at 30 mg three times per week and escalated to weekly dosing over four weeks, culminating with 90 mg weekly. One dose limiting toxicity of a rituximab infusion reaction was seen in cohort 2, but the regimen was otherwise well tolerated without evidence of differential toxicity by cohort. The overall response rate by National Cancer Institute-Working Group criteria was 61%, and the rate of complete bone marrow response was 43%, most of whom were negative for minimal residual disease. The addition of CT scan evaluation per International Workshop on Chronic Lymphocytic Leukemia 2008 criteria reduced the overall response rate to 14%. Median overall survival was 35 months, with 12 patients able to proceed to stem cell transplantation. Pharmacokinetic studies showed that chronic lymphocytic leukemia involving more than 80% of the bone marrow at study start was associated with lower trough concentrations of alemtuzumab and rituximab, and that higher trough serum concentrations of alemtuzumab were associated with complete bone marrow clearance. We conclude that escalated subcutaneous doses of alemtuzumab given weekly are well tolerated and result in excellent bone marrow clearance of chronic lymphocytic leukemia, helping patients to proceed to stem cell transplantation. This study is registered at ClinicalTrials.gov (Identifier:00330252).

Idelalisib is a small-molecule inhibitor of PI3Kd with demonstrated efficacy for the treatment of relapsed/refractory chronic lymphocytic leukemia (CLL). To evaluate idelalisib as front-line therapy, we enrolled 24 subjects in a phase 2 study consisting of 2 months of idelalisib monotherapy followed by 6 months of combination therapy with idelalisib and the anti-CD20 antibody ofatumumab. After a median follow-up period of 14.7 months, hepatotoxicity was found to be a frequent and often severe adverse event. A total of 19 subjects (79%) experienced either grade >= 1 ALT or AST elevation during the study, and 13 subjects (54%) experienced grade >= 3 transaminitis. The median time to development of transaminitis was 28 days, occurring before ofatumumab introduction. Younger age and mutated immunoglobulin heavy chain status were significant risk factors for the development of hepatotoxicity. Multiple lines of evidence suggest that this hepatotoxicity was immune mediated. A lymphocytic infiltrate was seen on liver biopsy specimens taken from 2 subjects with transaminitis, and levels of the proinflammatory cytokines CCL-3 and CCL-4 were higher in subjects experiencing hepatotoxicity. All cases of transaminitis resolved either by holding the drug, initiating immunosuppressants, or both, and rates of recurrent toxicity were lower in patients taking steroids when idelalisib was reinitiated. A decrease in peripheral blood regulatory T cells was seen in patients experiencing toxicity on therapy, which is consistent with an immune-mediated mechanism. These results suggest that caution should be taken as drugs within this class are developed for CLL, particularly in younger patients who have not received prior disease-specific therapy. This study was registered at www.clinicaltrials.gov as #NCT02135133

Summary Esophageal symptoms are common during radiation and chemotherapy. It is unclear how often these symptoms persist after therapy. We retrospectively reviewed medical records of 320 adults treated for nonmetastatic breast cancer (84), lung cancer (109), or Hodgkin and non-Hodgkin lymphoma (127) who were disease-free at 10–14 months after therapy. Treatment included chemotherapy with or without nonmediastinal radiation therapy (150 patients), chemotherapy plus sequential mediastinal radiation therapy (MRT) (48 patients), chemotherapy plus concurrent MRT (61 patients), or non-MRT only (61 patients). Proton pump inhibitor use was documented. All treatment groups had similar prevalence of the esophageal symptom of heartburn before therapy. Rates were higher during treatment in those who received MRT with or without chemotherapy, but declined by 10–14 months after treatment. However, low baseline rates of dysphagia (4%) and odynophagia (2%) increased significantly after combined chemotherapy and MRT to 72% for dysphagia and 62% for odynophagia (P

Over 90% of drugs with preclinical activity fail in human trials, largely due to insufficient efficacy. We hypothesized that adequately powered trials of patient-derived xenografts (PDX) in mice could efficiently define therapeutic activity across heterogeneous tumors. To address this hypothesis, we established a large, publically available repository of well-characterized leukemia and lymphoma PDXs that undergo orthotopic engraftment called the Public Repository of Xenografts (PRoXe; www.proxe.org). PRoXe includes all de-identified information relevant to the primary specimens and the PDXs derived from them. Using this repository, we demonstrate that large studies of acute leukemia PDXs that mimic human randomized clinical trials can characterize drug efficacy and generate transcriptional, functional and proteomic biomarkers in both treatment-naïve and relapsed/refractory disease.

Diffuse large B-cell lymphoma is an aggressive non-Hodgkin's lymphoma without a standard therapy for patients who relapse after or are not eligible for salvage autologous stem cell transplantation. In vitro analysis of lymphoma cell lines has shown that everolimus can inhibit cell cycle progression in vitro and inhibitors of the mammalian target of rapamycin have already demonstrated single-agent activity in relapsed non-Hodgkin's lymphomas including diffuse large B-cell lymphoma, validating mammalian target of rapamycin as a viable therapeutic target. We performed an open label phase II study of everolimus, an inhibitor of mammalian target of rapamycin, in combination with rituximab to examine efficacy and tolerability in patients with relapsed/refractory diffuse large B-cell lymphoma. Eligible patients were treated with everolimus 10 mg by mouth once daily on days 1-28 of a 28-day cycle with rituximab administered weekly during cycle one and then on day one of subsequent cycles. Patients were treated for a total of 12 cycles or until disease progression. The primary end-point was objective response rate, with secondary end-points being toxicity, progression-free survival, duration of response, and overall survival. Twenty-six patients (24 evaluable) were enrolled and had an overall response rate of 38% [90% CI (21%-56%)] with three complete responses and six partial responses among these 24 patients. The median duration of response among responders was 8.1 months. At a median follow-up of 12 months, the overall survival rate was 37% [90% CI (20%-54%)]. The most common grade 3 to 4 toxicities were neutropenia, anemia, and thrombocytopenia. In conclusion, everolimus in combination with rituximab is well tolerated and demonstrates activity in relapsed diffuse large B-cell lymphoma. Further studies of this combination are warranted. Clinicaltrials.gov identifier: NCT00869999

Disease overview: Follicular lymphoma (FL) is generally an indolent B-cell lymphoproliferative disorder of transformed follicular center B cells. FL is characterized by diffuse lymphoadenopathy, involvement of bone marrow, splenomegaly, and less commonly other extranodal sites of involvement. In general, cytopenias can occur but constitutional symptoms of fever, nightsweats, and weight loss are uncommon. Diagnosis: Diagnosis is based on histology of preferably a biopsy of a lymph node. Immunohistochemical staining is positive in virtually all cases for cell surface CD19, CD20, CD10, and monoclonal immunoglobulin, as well as cytoplasmic expression of bcl-2 protein. The overwhelming majority of cases have the characteristic t(14;18) translocation involving the IgH/bcl-2 genes. Risk stratification: The FL International Prognostic Index prognostic model for FL uses five independent predictors of inferior survival: age > 60 years, hemoglobin normal, Ann Arbor stage III/IV, number of involved nodal areas > 4. The presence of 0, 1, 2, and ≥ 3 adverse factors defines low, intermediate, and high-risk disease with median 10-year survivals in the pre-rituximab era of ∼71, 51, and 36 months, respectively. With the use of more modern therapies, specifically anti-CD20 monoclonal antibody, the outcome has improved. Risk-adapted therapy: Observation continues to be adequate for asymptomatic patients with low bulk disease and no cytopenias. For patients needing therapy, most patients are treated with chemotherapy plus rituximab, which has improved response rates, duration of response, and overall survival. Randomized studies have shown additional benefit for maintenance rituximab both following chemotherapy-rituximab and single-agent rituximab. Autologous stem cell transplantation (SCT) has not shown a survival benefit in first remission patients. SCT including both autologous and allogeneic SCT or experimental agent therapy is considered for recurrent disease. Am. J. Hematol. © 2012 Wiley Periodicals, Inc.

PURPOSE OF REVIEW In this article, we focus on the epidemiology, outcomes, and treatment options of early stage follicular lymphoma. RECENT FINDINGS Radiation therapy has been the predominant treatment for patients with early stage follicular lymphoma for decades. It is associated with a 10-year progression-free survival of 45-60%, thought to represent cures in this otherwise incurable disease with conventional modalities. Limiting the radiation field and dose does not diminish outcomes. On the contrary, the addition of chemotherapy does not benefit this patient population as a whole. The use of polymerase chain reaction for Bcl-2 gene rearrangements to detect molecular disease, however, may identify patients with early occult disseminated disease, who are at risk for relapse and would benefit from the addition of systemic therapy. For patients in whom radiation would be too toxic or prefer to not have radiation, observation is a reasonable alternative and a proportion of patients observed do not require therapy for a number of years. Despite the potential cures achieved by radiation therapy, a minority of patients in the United States receive such therapy; the majority are instead observed or treated with chemoimmunotherapy. SUMMARY Patients with early stage follicular lymphoma enjoy excellent outcomes following definitive radiation therapy, many of whom may even be cured. The addition of other therapies has not enhanced cure rates but identifying patients at greatest risk for disease relapse may change this paradigm. Despite the proven success of radiation, the majority of early stage follicular lymphoma patients in the United States do not receive radiation.

Purpose: The disease course of chronic lymphocytic leukemia (CLL) varies significantly within cytogenetic groups. We hypothesized that high-resolution genomic analysis of CLL would identify additional recurrent abnormalities associated with short time-to-first therapy (TTFT). Experimental Design: We undertook high-resolution genomic analysis of 161 prospectively enrolled CLLs using Affymetrix 6.0 SNP arrays, and integrated analysis of this data set with gene expression profiles. Results: Copy number analysis (CNA) of nonprogressive CLL reveals a stable genotype, with a median of only 1 somatic CNA per sample. Progressive CLL with 13q deletion was associated with additional somatic CNAs, and a greater number of CNAs was predictive of TTFT. We identified other recurrent CNAs associated with short TTFT: 8q24 amplification focused on the cancer susceptibility locus near MYC in 3.7%; 3q26 amplifications focused on PIK3CA in 5.6%; and 8p deletions in 5% of patients. Sequencing of MYC further identified somatic mutations in two CLLs. We determined which catalytic subunits of phosphoinositide 3-kinase (PI3K) were in active complex with the p85 regulatory subunit and showed enrichment for the α subunit in three CLLs carrying PIK3CA amplification. Conclusions: Our findings implicate amplifications of 3q26 focused on PIK3CA and 8q24 focused on MYC in CLL., Dana-Farber Cancer Institute. Center for Cancer Genome Discovery, Dana-Farber Cancer Institute (Dana-Farber Strategic Plan Initiative), Dana-Farber Cancer Institute. Center for Cancer Computational Biology, Damon Runyon Cancer Research Foundation (CI-38-07), Fonds voor Wetenschappelijk Onderzoek--Vlaanderen, Burroughs Wellcome Fund (Career Award at the Scientific Interface), National Institutes of Health (U.S.) (5PO1-CA120964), National Institutes of Health (U.S.) (5P30-CA006516), National Institutes of Health (U.S.) (NIH 5 PO1 CA092625), National Institutes of Health (U.S.) (K23 CA115682), National Institutes of Health (U.S.) (Pioneer Award), Merkin Family Foundation for Stem Cell Research, Howard Hughes Medical Institute

Purpose This study sought to quantify the risk of radiation pneumonitis (RP) in Hodgkin lymphoma (HL) patients receiving mediastinal radiation therapy (RT) and to identify predictive factors for RP. Methods and Materials We identified 75 patients with newly diagnosed HL treated with mediastinal RT and 17 patients with relapsed/refractory HL treated with mediastinal RT before or after transplant. Lung dose–volumetric parameters including mean lung dose and percentage of lungs receiving 20 Gy were calculated. Factors associated with RP were explored by use of the Fisher exact test. Results RP developed in 7 patients (10%) who received mediastinal RT as part of initial therapy (Radiation Therapy Oncology Group Grade 1 in 6 cases). A mean lung dose of 13.5 Gy or greater ( p = 0.04) and percentage of lungs receiving 20 Gy of 33.5% or greater ( p = 0.009) significantly predicted for RP. RP developed in 6 patients (35%) with relapsed/refractory HL treated with peri-transplant mediastinal RT (Grade 3 in 4 cases). Pre-transplant mediastinal RT, compared with post-transplant mediastinal RT, significantly predicted for Grade 3 RP (57% vs. 0%, p = 0.015). Conclusions We identified threshold lung metrics predicting for RP in HL patients receiving mediastinal RT as part of initial therapy, with the majority of cases being of mild severity. The risk of RP is significantly higher with peri-transplant mediastinal RT, especially among those who receive pre-transplant RT.

Pneumonitis is a complication of high-dose chemotherapy and autologous stem cell transplant (HDC-ASCT) regimens containing BCNU. Our goal was to define the incidence and risk factors for pneumonitis in patients with lymphoma receiving a uniform conditioning regimen in the modern era. We studied 222 patients who received HDC-ASCT using cyclophosphamide, BCNU and VP-16 (CBV). Pneumonitis incidence was 22%, with 19% receiving systemic corticosteroid treatment and 8% requiring inpatient hospitalization for pneumonitis. Three patients died secondary to pneumonitis-related complications. The following variables were independently associated with pneumonitis: prior mediastinal radiation (odds ratio [OR] 6.5, 95% confidence interval [CI] 2.3-18.9, p = 0.0005), total BCNU dose above 1000 mg (OR 3.4, 95% CI 1.3-8.7, p = 0.012) and age less than 54 (OR 3.0, 95% CI 1.4-6.5, p = 0.0037). Increased vigilance for symptoms of pneumonitis is warranted for patients with prior mediastinal radiation and for younger patients, and dose reduction may be considered for patients who would receive greater than 1000 mg of BCNU.

Disease overview: Follicular lymphoma (FL) is generally an indolent B-cell lymphoproliferative disorder of transformed follicular center B cells. FL is characterized by diffuse lymphoadenopathy, bone marrow involvement, splenomegaly, and less commonly other extranodal sites of involvement. In general, cytopenias can occur but constitutional symptoms of fever, nightsweats, and weight loss are uncommon. Diagnosis: Diagnosis is based on histology of preferably biopsy of a lymph node. Immunohistochemical staining is positive in virtually all cases for cell surface CD19, CD20, CD10 and monoclonal immunoglobulin, as well as cytoplasmic expression of bcl-2 protein. The overwhelming majority of cases have the characteristic t(14;18) translocation involving the IgH/bcl-2 genes. Risk stratification: The Follicular Lymphoma International Prognostic Index prognostic model for FL uses five independent predictors of inferior survival: age > 60 years, hemoglobin normal, Ann Arbor stage III/IV, number of involved nodal areas > 4. The presence of 0–1, 2, and ≥3 adverse factors defines low, intermediate, and high-risk disease with median 10 year survivals in the pre-rituximab era of approximately 71, 51, and 36 months, respectively. With the use of more modern therapies, specifically anti-CD20 monoclonal antibody, the outcome has improved. Risk-adapted therapy: Observation continues to be adequate for asymptomatic patients with low bulk disease and no cytopenias. For patients needing therapy, most patients are treated with chemotherapy plus rituximab, which has improved response rates, duration of response, and overall survival. Randomized studies have shown additional benefit for maintenance rituximab both following chemotherapy-rituximab and single agent rituximab. Autologous stem cell transplantation has not shown a survival benefit in first remission patients. Stem cell transplantation (SCT) including both autologous and allogeneic SCT or experimental agent therapy is considered for recurrent disease. Am. J. Hematol. 86:769-775, 2011. © 2011 Wiley-Liss, Inc.

Follicular dendritic cells (FDC) are an important subset of stromal cells within the germinal centres of lymphoid tissues. They are specialized to trap and retain antigen-containing immune complexes on their surfaces to promote B-cell maturation and immunoglobulin isotype class-switching. However, little is known of the cell types from which FDC originate. To address fundamental questions associated with the relationships between FDC and other cell populations, we took advantage of the growing body of publicly available data for transcriptome analysis. We obtained a large number of gene expression data files from a range of different primary mouse cells and cell lines and subjected these data to network-based cluster analysis using BIOLAYOUT EXPRESS(3D). Genes with related function clustered together in distinct regions of the graph and enabled the identification of transcriptional networks that underpin the functional activity of distinct cell populations. Several gene clusters were identified that were selectively expressed by cells of mesenchymal lineage and contained classic mesenchymal cell markers and extracellular matrix genes including various collagens, Acta2, Bgn, Fbn1 and Twist1. Our analysis showed that FDC also express highly many of these mesenchyme-associated genes. Promoter analysis of the genes comprising the mesenchymal clusters identified several regulatory motifs that are binding sites for candidate transcription factors previously known to be candidate regulators of mesenchyme-specific genes. Together, these data suggest FDC are a specialized mesenchymal cell population within the germinal centres of lymphoid tissues.

Reduced-intensity conditioning (RIC) hematopoietic SCT (HSCT) is a potentially curative therapeutic option for patients with advanced follicular lymphoma (FL), but disease relapse remains the most common cause of failure. Radioimmunoconjugates administered before RIC allo-HSCT may enhance cytoreduction and allow more time for GVL effect to develop without the associated toxicity of a myeloablative HSCT. We performed a retrospective study to describe the outcomes of patients with relapsed, refractory or transformed FL who received yttrium-90 ((90)Y)-ibritumomab tiuxetan followed by fludarabine and low-dose BU RIC allogeneic HSCT at the Dana-Farber Cancer Institute between 2006 and 2009, inclusively. Twelve patients were identified with a median age of 55 (40-66) years and a median number of lines of therapy of 5 (2-10). Two patients (17%) had transformed to a more aggressive histology and five (42%) had chemorefractory FL. Cumulative incidences of grade II-IV acute GVHD at 100 days were 17% (±11%) and chronic GVHD at 12 months were 63% (±19%). Two-year non-relapse mortality was 18% (±12%). Two-year OS and PFS were 83% (±11%) and 74% (±13%), respectively. This treatment is associated with favorable outcomes including acceptable rates of GVHD and relapse in advanced FL patients, and warrants prospective studies.

Background: Induction chemoimmunotherapy followed by autologous stem cell transplantation (ASCT) is a standard of care for transplant eligible (TE) patients (pts) with untreated mantle cell lymphoma (uMCL); however, there is no consensus on the optimal induction regimen. The addition of rituximab + high-dose cytarabine (RC) to an RCHOP-like regimen is associated with better outcomes. In addition, two randomized trials have demonstrated superior efficacy and tolerability for rituximab/bendamustine (RB) compared to RCHOP for uMCL. Based on this, we conducted a phase 2 trial of 3 cycles of RB followed by 3 cycles of RC in 23 TE pts with uMCL, with encouraging preliminary results (Armand, BJH 2016). Pts continued to be followed for relapse and survival. Meanwhile, RB/RC became the standard frontline regimen at Dana-Farber Cancer Institute (DFCI). Simultaneously, investigators at Washington University in St. Louis (WUSTL) initiated a similar study of alternating cycles of RB/RC for uMCL. Herein, we report the results of both phase 2 trials as well as the off-trial experience. Methods: In the DFCI trial, TE pts (age 18-69) with uMCL were treated with 3 cycles of RB (R 375 mg/m2 d1, B 90 mg/m2 d1-2) followed by 3 cycles of RC (R 375 mg/m2 d1, C 3gm/m2 BID d1-2 with dose reductions for age, renal dysfunction, or pre-existing neurotoxicity). Off-trial pts treated with RB/RC at DFCI or in consulting community practices were retrospectively identified using clinical and pharmacy databases. In the WUSTL trial, TE pts (age 18-65) received alternating cycles of RB (cycles 1, 3, 5) and RC (cycles 2, 4, 6) (same dosing as above). Response assessments were made using CT scans for the DFCI trial and PET/CT for the WUSTL trial and DFCI off-trial pts. Results: In total, 86 pts (23 DFCI trial, 49 DFCI off-trial, 14 WUSTL trial) were treated with RB/RC. The median age was 57 (range 30-72). Pts in the WUSTL cohort were more likely to be male, have a high MIPI score, and have blastoid variant (Table). 94% of pts completed 6 cycles of RB/RC therapy. Off-trial pts were more likely to receive a lower starting dose (≤ 2gm/m2) of cytarabine (76%) compared to trial pts (38%). At the EOI, the overall response rate and CRR were 98% and 92%, respectively, with similar response rates across cohorts (Table). 73 pts (85%) subsequently underwent ASCT and 4 additional pts (5%) have ASCTs planned. 9 pts did not undergo ASCT because of persistent or PD (n=3), prolonged cytopenias (n=3), an incidentally identified ASXL1 mutation without cytopenias (n=1), pt preference (n=1), and inadequate stem cell collection (n=1). Delayed platelet engraftment after ASCT was seen for pts receiving alternating cycles of RB/RC compared to sequential RB/RC at day 30 (plts 2gm/m2 was also associated with reduced 30-day platelet count (plts Median follow-up was 32m (range 4-69m) among survivors overall (54m for DFCI trial, 28m for DFCI off-trial, 19m for WUSTL trial). The 24m and 48m PFS for the entire cohort were 88% (95CI 77-93) and 80% (95CI 66-89), respectively (Figure, panel A); the 24m and 48m OS were 96% (95CI 89-99) and 92% (95CI 81-97), respectively. PFS and OS were similar across cohorts with a trend towards inferior PFS in the higher-risk WUSTL cohort (Figure, panel B). PFS was similar among non-trial pts treated at DFCI (n=32) and in community centers (n=17). In univariate analyses, a higher cytarabine dose (>2gm/m2) was not associated with improved PFS, while blastoid or pleomorphic variant (HR 4.5, p=0.016) and high-risk MIPI score (HR 4.0, p=0.034) were both associated with inferior PFS. Conclusions: Induction therapy with RB/RC followed by ASCT achieved high rates of durable remissions in two phase 2 clinical trials. Similarly favorable outcomes were observed with off-trial use of this regimen both at an academic center and in community practices. RB/RC is therefore an excellent choice of induction therapy for TE pts with uMCL, and could be further tested in comparative prospective trials. Sequential, rather than alternating, RB/RC cycles and lower dose cytarabine may reduce the risk of prolonged thrombocytopenia post-ASCT. Figure 1. Figure 1. Disclosures Kahl: Juno: Consultancy; Seattle Genetics: Consultancy; Celgene: Consultancy; Abbvie: Consultancy; AstraZeneca: Consultancy; Genentech: Consultancy; Acerta: Consultancy; ADC Therapeutics: Consultancy; CTI: Consultancy; Gilead: Consultancy. LaCasce:Research to Practice: Speakers Bureau; Bristol-Myers Squibb: Other: Data safety and monitoring board; Seattle Genetics: Consultancy, Honoraria; Humanigen: Consultancy, Honoraria. Jacobson:Bayer: Consultancy; Novartis: Consultancy; Precision Bioscience: Consultancy; Humanigen: Consultancy; Kite: Consultancy; Pfizer: Consultancy. Davids:Gilead: Membership on an entity's Board of Directors or advisory committees; Astra-Zeneca: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Roche/Genentech: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Pharmacyclics: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; AbbVie, Inc: Consultancy, Membership on an entity's Board of Directors or advisory committees; BMS: Research Funding; Janssen: Consultancy, Membership on an entity's Board of Directors or advisory committees; MEI Pharma: Consultancy, Research Funding; Surface Oncology: Research Funding; Merck: Consultancy; Verastem: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Consultancy; TG Therapeutics: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding. Brown:Sun Pharmaceutical Industries: Research Funding; Roche/Genentech: Consultancy; Pharmacyclics: Consultancy; Morphosys: Membership on an entity's Board of Directors or advisory committees; Janssen: Consultancy; Invectys: Membership on an entity's Board of Directors or advisory committees; Gilead: Consultancy, Research Funding; Genentech: Consultancy; Celgene: Consultancy; Boehringer: Consultancy; Beigene: Membership on an entity's Board of Directors or advisory committees; Acerta / Astra-Zeneca: Membership on an entity's Board of Directors or advisory committees; Abbvie: Consultancy; Verastem: Consultancy, Research Funding; Loxo: Consultancy; TG Therapeutics: Consultancy; Sunesis: Consultancy. Bartlett:Seattle Genetics: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Research Funding; Celgene: Research Funding; Forty Seven: Research Funding; Pharmacyclics: Research Funding; Merck & Co: Research Funding; Affimed: Research Funding; Novartis: Research Funding; ImaginAB: Research Funding; Astra Zeneca: Research Funding; Bristol-Meyers Squibb: Research Funding; Immune Design: Research Funding; Genentech: Research Funding; Pfizer: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; KITE: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Gilead: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Acerta: Membership on an entity's Board of Directors or advisory committees; Pharmacyclics: Research Funding; Novartis: Research Funding; Millennium: Research Funding. Armand:Merck: Consultancy, Research Funding; Adaptive: Research Funding; Otsuka: Research Funding; Affimed: Consultancy, Research Funding; Pfizer: Consultancy; Infinity: Consultancy; Bristol-Myers Squibb: Consultancy, Research Funding; Roche: Research Funding; Tensha: Research Funding. Jacobsen:Seattle Genetics: Consultancy; Merck: Consultancy.

Background: The leading cause of death after high-dose chemotherapy and autologous stem cell transplantation (ASCT) for relapsed / refractory (R/R) diffuse large B-cell lymphoma (DLBCL) remains disease relapse. Except for specific subsets, DLBCL appears to have relatively low susceptibility to single-agent PD-1 blockade. However, administering PD-1 blockade early after ASCT could leverage the remodeling immune landscape and minimal residual disease state to increase the therapeutic effect of PD-1 blockade and decrease the relapse rate after ASCT. A prior study with pidilizumab showed encouraging results in this setting (Armand et al. JCO 2013;31:4199-206), but the specificity of that antibody is still under investigation. We therefore conducted a phase 2 multi-center single-arm study of the anti-PD-1 monoclonal antibody pembrolizumab (pembro) in patients with chemosensitive DLBCL after ASCT. Another arm of this study enrolled pts with R/R classical Hodgkin lymphoma and will be presented separately. Methods: Patients ≥ 18y with R/R DLBCL who had received no more than 3 lines of prior therapy and had undergone ASCT with chemosensitive disease were enrolled on this study. In addition to meeting standard eligibility criteria for pembro treatment, pts had to have recovered from ASCT toxicities and had to begin study treatment within 60 days of stem cell infusion, with a goal of starting treatment within 21 days of hospital discharge. All patients received pembro 200mg IV every 3 weeks for 8 cycles. PET-CT scans were obtained at post-ASCT baseline, after 3 and 7 cycles, then at 12 and 18 months post-ASCT. The primary endpoint was the progression-free survival rate (PFS) at 18 months after ASCT, assessed using the International Harmonization Project 2007 criteria, with the approach considered promising if 22 patients were alive and in remission at 18 months. Results: 31 pts were enrolled and 2 withdrew consent before starting treatment. Among the 29 eligible pts, median age was 57 (22-76). Prior to ASCT, 18 (62%) were in CR and 11 (38%) were in PR. At study baseline (post-ASCT), 25 (86%) were in CR. 18 pts (62%) completed all 8 cycles of pembro per protocol. 11 pts (38%) stopped pembro early for pt choice (n=1, after febrile neutropenia), toxicity (n=6, including 3 pts with gr3 pneumonitis, 1 with g3 hepatitis, 1 with gr4 aplastic anemia) or progressive disease (n=4). 23 pts (79%) experienced a total of 57 gr3 or higher adverse events (AEs). The most common gr4 AE was neutropenia (n=6, 21%). Concerning related AEs, 9 pts (31%) experienced 14 gr3-4 AEs at least probably related to pembro including neutropenia (4 gr3, 1 gr 4) and pneumonitis (2 gr3). 10 pts (34%) experienced at least one immune-related AE of gr2 or higher severity including pneumonitis (n=1 gr2, n=2 gr3), transaminitis (n=1 gr2, n=1 gr3) and rash (n=1 gr2, n=1 gr3). There were no treatment-related deaths. Among the 29 eligible pts, 1 patient withdrew consent after cycle 1 and 1 pt was lost to follow-up after the 12m assessment (in CR). 27 pts (93%) were evaluable for the primary endpoint. 10 patients (34%, 95% CI: 18-54%) experienced disease relapse at a median of 5 months (3-18) after ASCT, and all other evaluable patients (n=17, 59%, 95% CI: 39-76%) were in CR at the 18m timepoint. 2 pts have died, both of whom had relapse at 3m after ASCT. Correlative studies including immune reconstitution and MRD analyses are ongoing. Conclusions: Pembrolizumab administered after ASCT in patients with R/R DLBCL is feasible with toxicity similar to its use in the R/R setting for other hematological malignancies. The high rate of neutropenia on this study, which is not a common AE of pembro in other settings, may be related to the burden of prior therapy or possibly to an accentuated toxicity of pembro in this specific patient population. The 18-month progression-free rate did not meet the protocol-specified primary objective, and therefore does not support a larger confirmatory study. Future studies in this setting should likely focus on specific subsets of DLBCL, e.g. primary mediastinal BCL, EBV+ DLBCL, T cell histiocyte rich LCL, which may be especially sensitive to PD1 blockade. Disclosures Chen: REGiMMUNE: Consultancy; Magenta Therapeutics: Consultancy; Incyte: Consultancy, Membership on an entity's Board of Directors or advisory committees; Takeda Pharmaceuticals: Consultancy. Armand:Pfizer: Consultancy; Adaptive: Research Funding; Merck: Consultancy, Research Funding; Infinity: Consultancy; Affimed: Consultancy, Research Funding; Otsuka: Research Funding; Bristol-Myers Squibb: Consultancy, Research Funding; Roche: Research Funding; Tensha: Research Funding. Herrera:Seattle Genetics: Research Funding; KiTE Pharma: Consultancy, Research Funding; Gilead Sciences: Research Funding; Merck, Inc.: Consultancy, Research Funding; Bristol-Myers Squibb: Consultancy, Research Funding; Pharmacyclics: Consultancy, Research Funding; AstraZeneca: Research Funding; Genentech: Consultancy, Research Funding; Immune Design: Research Funding. LaCasce:Humanigen: Consultancy, Honoraria; Bristol-Myers Squibb: Other: Data safety and monitoring board; Research to Practice: Speakers Bureau; Seattle Genetics: Consultancy, Honoraria. Jacobson:Pfizer: Consultancy; Precision Bioscience: Consultancy; Kite: Consultancy; Novartis: Consultancy; Bayer: Consultancy; Humanigen: Consultancy. Jacobsen:Merck: Consultancy; Seattle Genetics: Consultancy. Rodig:Merck & Co., Inc.: Research Funding; Affimed Inc.: Research Funding; KITE Pharma: Research Funding; Bristol-Meyers-Squibb: Research Funding. Shipp:AstraZeneca: Honoraria; Merck: Research Funding; Bayer: Research Funding; Bristol-Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding.

Background: Classical Hodgkin lymphoma (cHL) displays near-universal genetic deregulation of PD-1 ligand expression, and relapsed/refractory (R/R) cHL is uniquely sensitive to PD-1 blockade. However, such treatment for patients (pts) who relapse after or are ineligible for autologous stem cell transplantation (ASCT) appears to be rarely, if ever, curative. Deploying PD-1 blockade early after ASCT could leverage the remodeling immune landscape and minimal residual disease state to increase the cure rate of ASCT. We therefore conducted a phase 2 multi-center single-arm study of the anti-PD-1 monoclonal antibody pembrolizumab (pembro) in pts with chemosensitive R/R cHL after ASCT. Another arm of this study enrolled pts with R/R DLBCL and will be presented separately. Methods: Adult pts with R/R cHL who had received 2-3 lines of prior therapy and ASCT and who were chemosensitive prior to ASCT were enrolled on this study. In addition to meeting standard eligibility criteria for pembro treatment, pts had to have recovered from ASCT toxicities and begin study treatment within 60 days of stem cell infusion (goal within 21 days). They received pembro 200mg IV every 3 weeks for 8 cycles. PET-CT scans were obtained at post-ASCT baseline, after 3 and 7 cycles, then at 12 and 18 months post-ASCT. The primary endpoint was the progression-free survival rate (PFS) at 18 months after ASCT, assessed using International Harmonization Project 2007 criteria. Results: 31 pts were enrolled and 1 withdrew consent before starting treatment. Among the 30 eligible patients, median age was 33 (20-69). 26 pts (87%) were high-risk by virtue of primary refractory disease (57%), relapse within 12 months (17%), extranodal disease at relapse (27%) or absence of metabolic CR at ASCT (10%). At study baseline post-ASCT, 97% were in CR. 24 pts (80%) completed 8 cycles of pembro per protocol. 6 pts (20%) stopped pembro early for pt choice (n=2, including 1 pt with gr2 pneumonitis) or toxicity (n=4, including 2 pts with gr3 hepatitis, 1 with g3 pneumonitis, 1 with g2 diplopia). 9 pts (30%) experienced a total of 28 gr3 or higher adverse events (AEs). The most common gr4 AE was neutropenia (10%). 3 patients (10%) experienced 7 gr3-4 AEs at least probably related to pembro (gr3 diarrhea and gr3 eosinophilic colitis in 1 pt, gr3 leukopenia and gr4 neutropenia in 1 pt, gr3 leukopenia and gr3 ALT and AST elevation in 1 pt). 11 pts (37%) experienced at least one immune-related AE of gr2 or higher severity: pneumonitis (n=2 gr2, n=1 gr3), thyroid dysfunction (n=1 gr2), transaminitis (n=2 gr3), colitis/diarrhea (n=1 gr2, n=2 gr3), rash (n=2 gr2), pulmonary hemorrhage (n=1 gr3), arthritis (n=1 gr2), and increased creatinine (n=1 gr2). There was no treatment-related death. Among the 30 eligible pts, 2 were lost to follow-up after their 12m assessments (both in CR). 27 pts (90%) were evaluable for the primary endpoint (the last pt is still in follow-up and results will be updated for the meeting). 6 patients (20%) relapsed at a median of 8 months (3-18) from ASCT, and all other evaluable patients were in CR at the 18m timepoint. The KM estimate of 18m PFS for high-risk patients was 78% (95%CI 54-91). The 18m overall survival was 100%. Tumor biopsies from a pt who progressed on study demonstrated an increase in the %age of PD1+ T cells at progression, as well as an increase in the %age of PD-L1+ macrophages and PD-L1+ Reed-Sternberg cells (Figure). Other correlative studies including immune reconstitution and MRD analyses are ongoing. Conclusions: Pembrolizumab administered after ASCT in patients with R/R cHL has a safety profile that appears similar to its use in the R/R setting, although possibly with a higher rate of neutropenia. The 18-month progression-free rate in this high-risk cohort compares favorably with previous published studies, and supports the hypothesis that PD-1 blockade in this setting may increase the efficacy of ASCT. This should be tested in a randomized trial. Figure. Figure. Disclosures Armand: Pfizer: Consultancy; Affimed: Consultancy, Research Funding; Otsuka: Research Funding; Merck: Consultancy, Research Funding; Infinity: Consultancy; Adaptive: Research Funding; Bristol-Myers Squibb: Consultancy, Research Funding; Roche: Research Funding; Tensha: Research Funding. Chen:Incyte: Consultancy, Membership on an entity's Board of Directors or advisory committees; Takeda Pharmaceuticals: Consultancy; Magenta Therapeutics: Consultancy; REGiMMUNE: Consultancy. LaCasce:Humanigen: Consultancy, Honoraria; Research to Practice: Speakers Bureau; Bristol-Myers Squibb: Other: Data safety and monitoring board; Seattle Genetics: Consultancy, Honoraria. Jacobson:Pfizer: Consultancy; Humanigen: Consultancy; Precision Bioscience: Consultancy; Novartis: Consultancy; Kite: Consultancy; Bayer: Consultancy. Jacobsen:Merck: Consultancy; Seattle Genetics: Consultancy. Rodig:Bristol-Meyers-Squibb: Research Funding; KITE Pharma: Research Funding; Affimed Inc.: Research Funding; Merck & Co., Inc.: Research Funding. Shipp:AstraZeneca: Honoraria; Bristol-Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Bayer: Research Funding; Merck: Research Funding. Herrera:BMS: Consultancy, Research Funding; Merck: Consultancy, Research Funding; Genentech: Consultancy, Research Funding; Pharmacyclics: Consultancy, Research Funding; KiTE Pharma: Consultancy, Research Funding; Seattle Genetics: Research Funding; Immune Design: Research Funding; Astra Zeneca: Research Funding.

Approximately 10% of patients with chronic lymphocytic leukaemia (CLL) have a family history of the disease or a related lymphoproliferative disorder, yet the relationship of familial CLL to genomic abnormalities has not been characterized in detail. We therefore studied 75 CLL patients, half familial and half sporadic, using high-resolution array comparative genomic hybridization (CGH), in order to better define the relationship of genomic abnormalities to familial disease and other biological prognostic factors. Our results showed that the most common high-risk deletion in CLL, deletion 11q, was significantly associated with sporadic disease. Comparison of familial to sporadic disease additionally identified a copy number variant region near the centromere on 14q, proximal to IGH@, in which gains were associated both with familial CLL, and with mutated IGHV and homozygous deletion of 13q. Homozygous deletion of 13q was also found to be associated with mutated IGHV and low expression of ZAP-70, and a significantly longer time to first treatment compared to heterozygous deletion or lack of alteration. This study is the first high resolution effort to investigate and report somatic genetic differences between familial and sporadic CLL.

Histological transformation, a pivotal event in the natural history of cancers including lymphomas, is typically associated with more aggressive clinical behavior. L3055, a B lymphoma cell line of germinal center (GC) origin, is dependent on follicular dendritic cells (FDCs) for survival and proliferation, similar to GC-B cells. However, L3055 cells become less FDC-dependent after prolonged culture, which is analogous to transformation in vivo. Comparison of two L3055 subclones (i.e., the FDC-dependent indolent clone 12 and the FDC-independent aggressive clone 33) by DNA microarray revealed that CD9 was the most differentially expressed gene (P = 0.05). L3055-12 expresses high levels of CD9 while L3055-33 does not. Reduced levels or loss of CD9 expression is also observed in other CD9-positive B lymphoma cell lines. The resultant CD9-negative cells grow faster than CD9-positive cells due to their greater resistance to apoptosis. Furthermore, CD9-negative cells are less dependent on FDCs for their survival and growth compared with CD9-positive cells. CD9 down-regulation in B lymphomas appears to be controlled epigenetically, mainly through histone modifications. These findings imply that CD9 is inversely correlated with B lymphoma progression, and CD9 inactivation may play an important role in B lymphoma transformation.

Purpose To evaluate patient-specific immunotherapy with mitumprotimut-T (idiotype keyhole limpet hemocyanin [Id-KLH]) and granulocyte-macrophage colony-stimulating factor (GM-CSF) in CD20+ follicular lymphoma. Patients and Methods Patients with treatment-naive or relapsed/refractory disease achieving a complete response (CR), partial response (PR), or stable disease (SD) with four weekly rituximab infusions were randomly assigned to mitumprotimut-T/GM-CSF or placebo/GM-CSF, with doses given monthly for six doses, every 2 months for six doses, and then every 3 months until disease progression (PD). Randomization was stratified by prior therapy (treatment-naive or relapsed/refractory) and response to rituximab (CR/PR or SD). The primary end point was time to progression (TTP) from randomization. Results A total of 349 patients were randomly assigned; median age was 54 years, 79% were treatment naive, and 86% had stage III/IV disease. Median TTP was 9.0 months for mitumprotimut-T/GM-CSF and 12.6 months for placebo/GM-CSF (hazard ratio [HR] = 1.384; P = .019). TTP was comparable between the two arms in treatment-naive patients (HR = 1.196; P = .258) and shorter with mitumprotimut-T/GM-CSF in relapsed/refractory disease (HR = 2.265; P = .004). After adjusting for Follicular Lymphoma International Prognostic Index (FLIPI) scores, the difference in TTP between the two arms was no longer significant. Overall objective response rate, rate of response improvement, and duration of response were comparable between the two arms. Toxicity was similar in the two arms; 76% of adverse events were mild or moderate, and 94% of patients had injection site reactions. Conclusion TTP was shorter with mitumprotimut-T/GM-CSF compared with placebo/GM-CSF. This difference was possibly due to the imbalance in FLIPI scores.