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Selecting patients for phase I cancer trials is crucial to ensure a sufficient life expectancy. Frail patients, better suited for palliative care, should not be exposed to new drugs with minimal benefit. Enrolling patients at high risk of early death can jeopardize the study. Our analysis of two large precision medicine studies used tumor fraction from ctDNA to develop a predictive model, demonstrating notable predictive accuracy and aiding in patient selection., (© 2024. The Author(s).)

Background: Copy number alterations (CNA) are acquired during the evolution of cancers from their early stage to metastatic stage. This study aims at analysing the clinical value of the identified metastasis-associated CNAs both in metastatic breast cancers (mBCs) and early breast cancers (eBCs)., Methods: Single-nucleotide polymorphism (SNP)-array was performed on 926 biopsies from mBC patients, enrolled in SAFIR02-BREAST prospective trial. CNA profiles of eBCs from The Cancer Genome Atlas Breast Invasive Carcinoma (n = 770), Molecular Taxonomy of Breast Cancer International Consortium (n = 1620) and PACS04 trial (n = 243) cohorts were used as references for comparing mBCs and eBCs CNA profiles. Overall survival was the considered survival endpoint., Results: Among the twenty-one genes frequently altered in ER + /HER2- mBCs: focal amplification of TERT was associated with poor outcome in the ER + /HER2- mBC population. Among the ER + /HER2- mBCs patients for whom CDK4/6 inhibitors information before biopsies collection was available: we identified seven genes on post-treatment biopsies, including the cyclin-dependent kinase 4 (CDK4), which was amplified in 9.8% of the ER + /HER2- mBCs pretreated population, as compared to 1.5% in the ER + /HER2- mBCs unpretreated population (P = 2.82E-04) as well as the 3 eBC populations. CDK4 amplification was associated with poor outcome in the ER + /HER2- eBCs., Conclusions: This study provides insights into the biology of mBCs and identifies clinically useful genomic features for future improvement of breast cancer patient management., (© 2024. The Author(s).)

Anti-angiogenic agents elicit considerable immune modulatory effects within the tumor microenvironment, underscoring the rationale for synergistic clinical development of VEGF and immune checkpoint inhibitors in advanced gastric cancer (AGC). Early phase studies involving Asian patients demonstrated encouraging anti-tumor efficacies. We report the results of the REGOMUNE phase II study, in which Caucasian patients were administered regorafenib, a multi-tyrosine kinase inhibitor, in combination with avelumab, a PD-L1-targeting monoclonal antibody. This therapeutic regimen resulted in deep and durable responses in 19% of patients, with the median duration of response not yet reached. Notwithstanding, a significant proportion of AGC patients exhibited no therapeutic advantage, prompting investigations into mechanisms of inherent resistance. Comprehensive biomarker profiling elucidated that non-responders predominantly exhibited an augmented presence of M2 macrophages within the tumor microenvironment and a marked overexpression of S100A10 by neoplastic cells, a protein previously implicated in macrophage chemotaxis. Additionally, peripheral biomarker assessments identified elevated levels of cytokines, including CSF-1, IL-4, IL-8, and TWEAK, correlating with adverse clinical outcomes, thereby accentuating the role of macrophage infiltration in mediating resistance. These insights furnish an invaluable foundation for elucidating, and potentially circumventing, resistance mechanisms in current AGC therapeutic paradigms, emphasizing the integral role of tumor microenvironmental dynamics and immune modulation., (© 2024. The Author(s).)

Selective KRAS G12C inhibitors have been developed to covalently lock the oncogene in the inactive GDP-bound state. Two of these molecules, sotorasib and adagrasib, are approved for the treatment of adult patients with KRAS G12C -mutated previously treated advanced non-small cell lung cancer. Drug treatment imposes selective pressures leading to the outgrowth of drug-resistant variants. Mass sequencing from patients' biopsies identified a number of acquired KRAS mutations -both in cis and in trans- in resistant tumors. We demonstrate here that disease progression in vivo can also occur due to adaptive mechanisms and increased KRAS-GTP loading. Using the preclinical tool tri-complex KRAS G12C -selective covalent inhibitor, RMC-4998 (also known as RM-029), that targets the active GTP-bound (ON) state of the oncogene, we provide a proof-of-concept that the clinical stage KRAS G12C (ON) inhibitor RMC-6291 alone or in combination with KRAS G12C (OFF) drugs can be an alternative potential therapeutic strategy to circumvent resistance due to increased KRAS-GTP loading., (© 2024. The Author(s).)

We analyzed the antitumor activity of platinum-based chemotherapies and then immune checkpoint inhibitors (ICI) in all-comers patients with solid tumors having a somatic DNA damage repair gene alteration (DDR-GA) identified through a prospective precision medicine study (NCT02534649). Each DDR-GA was classified as pathogenic (Pa), probably pathogenic (PPa), and unknown pathogenicity (UPa) according to OncoKB and ClinVAR databases. Between January 2018 and May 2020, 662 patients were screened. One hundred ninety-nine tumors with DDR-GA were found in 121 (18.3%) patients. Ninety-six patients received platinum-based chemotherapy in the advanced setting. No difference in objective response rate (ORR) under platinum regimen was observed between the 3 DDR-GA groups. The only predictor of worse progression-free survival (PFS) in Cox regression was the existence of a Pa alteration compared to the UPa group: HR = 2.11 (95% CI = 1.2-3.7), P = .009. Forty-eight patients received ICI alone or in combination. We observed a significant trend in better ORR to ICI according to the DDR-GA status: 1/11 (9%) patients in UPa, 5/17 (29.4%) patients in PPa, and 9/20 (45%) patients in Pa (P = .003, Cochran-Armitage trend test), and an increased 6-month PFS probability of 11%, 44%, and 50% in the UPa, PPa, and Pa groups, respectively (P = .37, log-rank test). Overall, somatic pathogenic DDR-GAs were not associated with ORR or PFS to platinum-based chemotherapy in patients with unselected advanced solid tumors. However, DDR-GA seemed to impact ORR and PFS to ICI, paving the way for a therapeutic combination with ICI and molecules targeting the DDR mechanisms, which are currently evaluated in ongoing clinical trials., (© The Author(s) 2024. Published by Oxford University Press.)

The immune system can control cancer progression. However, even though some innate immune sensors of cellular stress are expressed intrinsically in epithelial cells, their potential role in cancer aggressiveness and subsequent overall survival in humans is mainly unknown. Here, we show that nucleotide-binding oligomerization domain-like receptor (NLR) family CARD domain-containing 4 (NLRC4) is downregulated in epithelial tumor cells of patients with colorectal cancer (CRC) by using spatial tissue imaging. Strikingly, only the loss of tumor NLRC4, but not stromal NLRC4, was associated with poor immune infiltration (mainly DCs and CD4+ and CD8+ T cells) and accurately predicted progression to metastatic stage IV and decrease in overall survival. By combining multiomics approaches, we show that restoring NLRC4 expression in human CRC cells triggered a broad inflammasome-independent immune reprogramming consisting of type I interferon (IFN) signaling genes and the release of chemokines and myeloid growth factors involved in the tumor infiltration and activation of DCs and T cells. Consistently, such reprogramming in cancer cells was sufficient to directly induce maturation of human DCs toward a Th1 antitumor immune response through IL-12 production in vitro. In multiple human carcinomas (colorectal, lung, and skin), we confirmed that NLRC4 expression in patient tumors was strongly associated with type I IFN genes, immune infiltrates, and high microsatellite instability. Thus, we shed light on the epithelial innate immune sensor NLRC4 as a therapeutic target to promote an efficient antitumor immune response against the aggressiveness of various carcinomas.

Atypical spindle cell/pleomorphic lipomatous tumor (ASPLT) is a recently described adipocytic tumor predominantly affecting the subcutaneous soft tissues of adults. Previous studies have shown that ASPLT follows a benign clinical course with a 4% to 12% local recurrence rate and no risk of dedifferentiation. Herein, we describe the clinicopathologic and molecular findings of 4 cases of ASPLT showing unequivocal sarcomatous transformation. Three patients were male and one was female, aged 65, 70, 74, and 78 years. Two cases presented as mass-forming lesions, while 1 case was incidentally discovered. The tumors measured 30, 55, 80, and 110 mm and occurred in the chest wall (n = 2) or arm (n = 2); all were subcutaneous. Microscopically, they showed a biphasic appearance comprising a low-grade ASPLT component and a high-grade sarcomatous component. The low-grade components showed features in the spectrum of either atypical pleomorphic lipomatous tumor (n = 2) or atypical spindle cell lipomatous tumor (n = 2). The high-grade components displayed leiomyosarcoma-like (n = 2), pleomorphic liposarcoma-like (n = 1) or undifferentiated sarcoma-like (n = 1) morphology. On immunohistochemistry, tumors were negative for MDM2 and showed loss of RB1 expression. In addition, the leiomyosarcoma-like areas seen in 2 cases were positive for smooth muscle actin and H-caldesmon. Single-nucleotide polymorphism array, performed in 3 cases, showed deletions of TP53, RB1, and flanking genes in both components. In contrast, the sarcomatous components showed more complex genomic profiles with rare segmental gains and recurrent loss of PTEN (n = 3), ATM (n = 2), and CDKN2A/B (n = 2) among other genes. Whole exome sequencing identified a TP53 variant in one case and an ATRX variant in another, each occurring in both tumor components. Limited clinical follow-up showed no recurrence or metastasis after 1 to 13 months (median, 7.5 months) postsurgical excision. Altogether, our data support that ASPLT can rarely develop sarcomatous transformation and offer insights into the molecular mechanisms underlying this event., (Copyright © 2024 United States & Canadian Academy of Pathology. Published by Elsevier Inc. All rights reserved.)

A close relationship has been demonstrated between genomic complexity and clinical outcome in uterine smooth muscle tumors. We studied the genomic profiles by array-CGH of 28 fumarate hydratase deficient leiomyomas and 37 leiomyomas with bizarre nuclei (LMBN) from 64 patients. Follow-up was available for 46 patients (from three to 249 months, mean 87.3 months). All patients were alive without evidence of disease. For 51 array-CGH interpretable tumors the mean Genomic Index (GI) was 16.4 (median: 9.8; from 1 to 57.8), significantly lower than the mean GI in LMS (mean GI 51.8, p < 0.001). We described three groups: (1) a group with FH deletion (24/58) with low GI (mean GI: 11 vs. 22,4, p = 0.02), (2) a group with TP53 deletion (17/58) with higher GI (22.4 vs. 11 p = 0.02), and (3) a group without genomic events on FH or TP53 genes (17/58) (mean GI:18.3; from 1 to 57.8). Because none of these tumors recurred and none showed morphological features of LMS we concluded that GI at the cut-off of 10 was not applicable in these subtypes of LM. By integration of all those findings, a GI <10 in LMBN remains a valuable argument for benignity. Conversely, in LMBN a GI >10 or alteration in tumor suppressor genes, should not alone warrant a diagnosis of malignancy. Nine tumors were tested with Nanocind CINSARC® signature and all were classified in low risk of recurrence. We propose, based on our observations, a diagnostic approach of these challenging lesions., (© 2024 Wiley Periodicals LLC.)

Aims: NTRK-rearranged sarcomas of the female genital tract mainly occur in the uterus (more commonly cervix than corpus) and are characterized by a "fibrosarcoma-like" morphology and NTRK gene rearrangements. These neoplasms may exhibit histological overlap with other entities and can present diagnostic difficulties without molecular confirmation. Pan-TRK immunohistochemistry was developed to identify tumours harbouring NTRK rearrangements. The aim of this study was to characterize pan-TRK immunohistochemical expression in a large cohort of gynaecological mesenchymal neoplasms and investigate the utility of pan-TRK immunohistochemistry to distinguish NTRK-rearranged sarcoma from its mimics., Methods and Results: A total of 473 gynaecological mesenchymal tumours (461 without known NTRK fusions and 12 NTRK-rearranged sarcomas) were selected. Pan-TRK immunohistochemistry (EPR17341, Abcam) was performed on whole tissue sections and tissue microarrays. Molecular interrogation of pan-TRK positive tumours was performed by RNA sequencing or fluorescence in situ hybridization (FISH). Of the 12 NTRK-rearranged sarcomas, 11 (92%) exhibited diffuse (≥70%) cytoplasmic pan-TRK staining with moderate/marked intensity, while the other was negative. Eleven (2.4%) additional tumours also exhibited pan-TRK immunohistochemical expression: three low-grade endometrial stromal sarcomas, seven high-grade endometrial stromal sarcomas, and an undifferentiated uterine sarcoma. Molecular confirmation of the absence of NTRK rearrangements was possible in nine of these tumours. Of these nine neoplasms, seven exhibited focal/multifocal (<70%) pan-TRK cytoplasmic staining with weak/moderate intensity., Conclusion: Even though pan-TRK immunohistochemical expression is not entirely sensitive or specific for NTRK-rearranged sarcomas, these neoplasms tend to exhibit diffuse staining of moderate/strong intensity, unlike its mimics. Pan-TRK should be performed in monomorphic uterine (corpus and cervix) spindle cell neoplasms that are negative for smooth muscle markers and hormone receptors and positive for CD34 and/ or S100. Ultimately, the diagnosis requires molecular confirmation., (© 2023 John Wiley & Sons Ltd.)

Aims: Idylla epidermal growth factor receptor ( EGFR ) is a fast and fully automated mutation assay that is easy to implement. However, under the Biocartis-recommended technical conditions, tissue sections are directly introduced into the cartridge, at the risk of exhausting the tumour sample. In this study, we evaluate the performance of Idylla EGFR on extracted DNA and discuss its place within the global non-small-cell lung cancer (NSCLC) screening strategy., Methods: 577 comparative tests between Idylla EGFR on extracted DNA and next-generation sequencing (NGS) were performed across two centres., Results: Preanalytical thresholds were established (20% tumour cell content, 50 ng DNA input) and challenged prospectively in routine practice. 16.8% of samples referred for screening were considered non eligible for Idylla EGFR testing. Due to discordant by design cases, Idylla EGFR sensitivity was 86.9% for currently actionable EGFR mutations. Idylla EGFR specificity was 100% in first-line screening. NGS was always feasible on the same DNA., Conclusion: Idylla EGFR on extracted DNA is feasible and enables tumour material to be saved compared with tissue section use. It is not necessary to replace the analytical thresholds of the Biocartis algorithm. Due to both the limits of the mutational repertoire and the high increase of targetable genes in NSCLC, the use of Idylla EGFR should be restricted to clinical emergency situations accompanied by NGS., Competing Interests: Competing interests: EK has received honoraria from Biocartis. The remaining authors declare no conflict of interest., (© Author(s) (or their employer(s)) 2023. No commercial re-use. See rights and permissions. Published by BMJ.)

Neoplasms harboring a KAT6B/A::KANSL1 fusion were initially reported as benign (leiomyomas) and malignant (leiomyosarcomas, low-grade endometrial stromal sarcomas [LG-ESSs]) uterine neoplasms. However, they may represent an emerging entity characterized by clinical aggressiveness contrasting with a rather reassuring microscopic appearance. Here, we aimed to confirm that this neoplasm is a distinct clinicopathologic and molecular sarcoma and identify criteria that should alert pathologists and lead to KAT6B/A::KANSL1 fusion testing in routine practice. Therefore, we conducted a comprehensive clinical, histopathologic, immunohistochemical, and molecular study, including array comparative genomic hybridization, whole RNA-sequencing, unsupervised clustering, and cDNA mutational profile analyses of 16 tumors with KAT6B::KANSL1 fusion from 12 patients. At presentation, patients were peri-menopausal (median, 47.5 years), and the primary tumors were located in the uterine corpus (12/12, 100%), with an additional prevesical location in 1 (8.3%) of 12 cases. The relapse rate was 33.3% (3/9). All tumors (16/16, 100%) showed morphologic and immunohistochemical features overlapping between leiomyoma and endometrial stromal tumors. A whirling recurrent architecture (resembling fibromyxoid-ESS/fibrosarcoma) was found in 13 (81.3%) of 16 tumors. All tumors (16/16, 100%) exhibited numerous arterioliform vessels, and 13 (81.3%) of 18 had large hyalinized central vessels and collagen deposits. Estrogen and progesterone receptors were expressed in 16 (100%) of 16 and 14 (87.5%) of 16 tumors, respectively. Array comparative genomic hybridization performed on 10 tumors classified these neoplasms as simple genomic sarcomas. Whole RNA-sequencing on 16 samples and clustering analysis on primary tumors found that the KAT6B::KANSL1 fusion always occurred between exons 3 of KAT6B and 11 of KANSL1; no pathogenic variant was identified on cDNA, all neoplasms clustered together, close to LG-ESS, and pathway enrichment analysis showed cell proliferation and immune infiltrate recruitment pathway involvement. These results confirm that the sarcomas harboring a KAT6B/A::KANSL1 fusion represent a distinct clinicopathologic entity, close to LG-ESS but different, with clinical aggressiveness despite a reassuring morphology, for which the KAT6B/A::KANSL1 fusion is the molecular driver alteration., (Copyright © 2023. Published by Elsevier Inc.)

Pan-Trk immunohistochemistry has been described as a screening test for the detection of NTRK fusions in a broad spectrum of tumor types. However, pan-Trk testing in the clinical setting may be limited by many factors, including analytical parameters such as clones, platforms, and protocols used. This study aimed to harmonize pan-Trk testing using various clones and immunohistochemical (IHC) platforms and to evaluate the level of analytical variability across pathology laboratories. We developed several IHC pan-Trk assays using clones EPR17341 (Abcam) and A7H6R (Cell Signaling Technology) on Ventana/Roche, Agilent, and Leica platforms. To compare them, we sent unstained sections of a tissue microarray containing 9 cases with NTRK3 fusions to participating laboratories, to perform staining on Ventana/Roche (10 centers), Agilent (4 centers), and Leica (3 centers) platforms. A ready-to-use pan-Trk IVD assay (Ventana/Roche) was also performed in 3 centers. All slides were centrally and blindly reviewed for the percentage of stained tumor cells. Laboratory-developed tests with clone EPR17341 were able to detect pan-Trk protein expression in all cases, whereas lower rates of positivity were observed with clone A7H6R. Moderate to strong variability of the positive cases rate was observed with both antibodies in each IHC platforms type and each of the positivity cut points evaluated (≥1%, ≥10%, and ≥50% of stained tumor cells). The rate of false-negative cases was lower when pan-Trk staining was assessed with the lowest positivity threshold (≥1%). In conclusion, most evaluated pan-Trk IHC laboratory-developed tests were able to detect NTRK3-fusion proteins; however, a significant analytical variability was observed between antibodies, platforms, and centers., (Copyright © 2023 United States & Canadian Academy of Pathology. Published by Elsevier Inc. All rights reserved.)

Infection of SARS-CoV-2 among health workers (HWs) in contact with cancer patients has been a major issue since the beginning of the pandemic. We aimed to assess the serological immune status of SARS-CoV-2 infection among these HWs. A prospective cohort study was initiated in the comprehensive cancer center of the Nouvelle-Aquitaine region (NA, France). Volunteer HWs working on March 2020 without active infection or symptoms of COVID-19 completed a self-questionnaire and had a blood test at inclusion, at 3 and 12 months. Positive serological status of SARS-CoV-2 infection was defined by anti-nucleocapsid antibodies and/or IgG anti-spike antibodies, except at 12 months due to vaccine. Half of the HWs were included (N = 517) and 89% were followed for three months (N = 500) and one year (N = 462). Seroprevalence of SARS-CoV-2 infection was 3.5% (95% CI: 1.9-5.1), 6.2% (95% CI: 4.1-8.3), and 10% (95% CI: 7.2-12.7) on June-September 2020, September 2020-January 2021, and June-October 2021, respectively. At 12 months, 93.3% had detectable antibodies with 80% vaccinated in the first three months of vaccine availability. The COVID-19-free policy of the institution, respect for barrier gestures, high and early vaccination of HWs, and low prevalence of SARS-CoV-2 in NA may explain the low rate of seropositivity among the HWs of the Institut Bergonié.

The median overall survival of metastatic esophagogastric adenocarcinoma is approximately twelve months. In fifteen years, major breakthrough have been the targeting of HER2 overexpression and more recently immunotherapy in patients with CPS≥5. Recent advances in molecular biology have identified some molecular alterations in esophageal adenocarcinoma, interesting to target. FGFR2 is overexpressed in one third of patients, and its targeting with a specific monoclonal antibody bemarituzumab showed a significant improvement in survival. Claudin 18.2 (CLDN 18.2) is overexpressed in at least a third of esophagogastric adenocarcinomas. The combination of zolbetuximab and chemotherapy provides a survival benefit, correlated with the intensity of CLDN 18.2 expression. The potential interest of targeting other pathways is under investigation in several trials with some encouraging preliminary data, and early trials in these indications, justifying considering large molecular screening in patients who might be candidate for early phase trial. Finally, with the recent advent of immunotherapy, one of the future challenges will be to optimize it through combination strategies with targeted therapies. The combination of anti-angiogenic and immunotherapy seems promising in gastric cancer., (Copyright © 2022 Société Française du Cancer. Published by Elsevier Masson SAS. All rights reserved.)

Mature tertiary lymphoid structures (mTLSs) are organized lymphoid structures containing B lymphocytes admixed to CD23+ follicular dendritic cells. Their presence has been linked to improved survival and sensitivity to immune checkpoint inhibitors in several cancers, emerging as a promising pancancer biomarker. However, the requirements for any biomarker are clear methodology, proven feasibility, and reliability. In 357 patients' samples, we studied tertiary lymphoid structures (TLSs) parameters using multiplex immunofluorescence (mIF), hematoxylin-eosin-saffron (HES) staining, double CD20/CD23 staining, and single CD23 immunohistochemistry. The cohort included carcinomas (n = 211) and sarcomas (n = 146), gathering biopsies (n = 170), and surgical specimens (n = 187). mTLSs were defined as TLSs containing either a visible germinal center on HES staining or CD23+ follicular dendritic cells. Focusing on 40 TLSs assessed using mIF, double CD20/CD23 staining was less sensitive than mIF to assess maturity in 27.5% (n = 11/40) but was rescued by single CD23 staining in 90.9% (n = 10/11). In 97 patients, several samples (n = 240) were reviewed to characterize TLS distribution. The likelihood of finding TLSs in surgical material was 6.1 higher than in biopsy and 2.0 higher in primary samples than in metastasis after adjustment with a type of sample. Interrater agreement rates over 4 examiners were 0.65 (Fleiss kappa, 95% CI [0.46, 0.90]) for the presence of TLS and 0.90 for maturity (95% CI [0.83, 0.99]). In this study, we propose a standardized method to screen mTLSs in cancer samples using HES staining and immunohistochemistry that can be applied to all specimens., (Copyright © 2023 United States & Canadian Academy of Pathology. Published by Elsevier Inc. All rights reserved.)

Context.—: Granulosa cell tumors (GCTs) of both adult (AGCT) and juvenile (JGCT) types can rarely be completely or dominantly cystic, creating diagnostic difficulty because the cyst lining epithelium is often denuded., Objective.—: To describe clinical, gross, microscopic, immunohistochemical, and molecular features of cystic GCTs with an emphasis on their differential diagnosis., Design.—: We report 80 cystic GCTs (24 AGCTs and 56 JGCTs) in patients from ages 3 to 83 years (average ages, 35 years for AGCT and 22 years for JGCT)., Results.—: Nineteen of 43 patients with known clinical information (3 AGCT and 16 JGCT) had androgenic manifestations. All tumors were greater than 8 cm (average, 17 cm) with minimal to absent gross solid component. Denudation of cells lining the cysts was prominent. Invagination of the epithelium into the cyst walls was a key diagnostic feature, was present as cords, trabeculae, solid nests, and small and large follicles, and was identified in most tumors (17 AGCTs and 45 JGCTs). Cytologic atypia was essentially absent in AGCTs, whereas 14 JGCTs showed moderate to severe atypia of bizarre type. A theca cell component was present in all tumors and was extensive in 54. A FOXL2 hotspot mutation was identified in 1 of 4 AGCTs tested., Conclusions.—: Despite extensive denudation, the finding of typical architectural patterns and cytologic features as well as, in some cases, androgenic manifestations helps differentiate cystic GCTs from follicle cysts, the most common and challenging differential diagnosis, as well as other cystic neoplasms that may enter the differential diagnosis. FOXL2 sequencing may show a false-negative result in cystic AGCT because of the limited number of cells present within the tumor sample., Competing Interests: The authors have no relevant financial interest in the products or companies described in this article., (© 2022 College of American Pathologists.)

Background: Cases of the spontaneous regression of multiple pulmonary metastases, after radiofrequency ablation (RFA), of a single lung metastasis, have been documented to be mediated by the immune system. The interaction of immune checkpoints, e.g., PD-1/PD-L1 and CTLA-4/CD80, may explain this phenomenon. The purpose of this study is to identify and quantify immune mechanisms triggered by RFA of pulmonary metastases originating from colorectal cancer., Methods: We used two-site time-resolved Förster resonance energy transfer as determined by frequency-domain FLIM (iFRET) for the quantification of receptor-ligand interactions. iFRET provides a method by which immune checkpoint interaction states can be quantified in a spatiotemporal manner. The same patient sections were used for assessment of ligand-receptor interaction and intratumoral T-cell labeling., Conclusion: The checkpoint interaction states quantified by iFRET did not correlate with ligand expression. We show that immune checkpoint ligand expression as a predictive biomarker may be unsuitable as it does not confirm checkpoint interactions. In pre-RFA-treated metastases, there was a significant and negative correlation between PD-1/PD-L1 interaction state and intratumoral CD3+ and CD8+ density. The negative correlation of CD8+ and interactive states of PD-1/PD-L1 can be used to assess the state of immune suppression in RFA-treated patients.

Cancer progression is driven in part by genomic alterations 1 . The genomic characterization of cancers has shown interpatient heterogeneity regarding driver alterations 2 , leading to the concept that generation of genomic profiling in patients with cancer could allow the selection of effective therapies 3,4 . Although DNA sequencing has been implemented in practice, it remains unclear how to use its results. A total of 1,462 patients with HER2-non-overexpressing metastatic breast cancer were enroled to receive genomic profiling in the SAFIR02-BREAST trial. Two hundred and thirty-eight of these patients were randomized in two trials (nos. NCT02299999 and NCT03386162) comparing the efficacy of maintenance treatment 5 with a targeted therapy matched to genomic alteration. Targeted therapies matched to genomics improves progression-free survival when genomic alterations are classified as level I/II according to the ESMO Scale for Clinical Actionability of Molecular Targets (ESCAT) 6 (adjusted hazards ratio (HR): 0.41, 90% confidence interval (CI): 0.27-0.61, P < 0.001), but not when alterations are unselected using ESCAT (adjusted HR: 0.77, 95% CI: 0.56-1.06, P = 0.109). No improvement in progression-free survival was observed in the targeted therapies arm (unadjusted HR: 1.15, 95% CI: 0.76-1.75) for patients presenting with ESCAT alteration beyond level I/II. Patients with germline BRCA1/2 mutations (n = 49) derived high benefit from olaparib (gBRCA1: HR = 0.36, 90% CI: 0.14-0.89; gBRCA2: HR = 0.37, 90% CI: 0.17-0.78). This trial provides evidence that the treatment decision led by genomics should be driven by a framework of target actionability in patients with metastatic breast cancer., (© 2022. The Author(s), under exclusive licence to Springer Nature Limited.)

Myxoinflammatory fibroblastic sarcoma (MIFS) is a rare soft tissue tumor with a predilection for the distal extremities and a tendency for local recurrence. Morphologically, MIFS consists of spindle and bizarre epithelioid cells resembling virocytes embedded in a fibrous to myxoid stroma with an abundant inflammatory infiltrate. Importantly, the molecular landscape of MIFS is wide and includes: VGLL3 amplification, BRAF fusion/amplification and OGA/TGFBR3 rearrangements. In this study, we describe a variant of MIFS showing a frequent nodular configuration associated with necrosis and recurrent YAP1::MAML2 fusions. The cohort consisted of 7 patients (4 females and 3 males) ranging in age from 21 to 71 years (median: 47 years). Two tumors (28%) occurred in acral locations while the remaining cases were more widely distributed (thigh, n = 2; arm, n = 1; neck; n = 1; chest-wall, n = 1). Tumor size ranged from 10 to 38 mm (median: 20 mm). Histologically, lesions frequently presented as nodules with central areas of necrosis, and were predominantly composed of sheets of epithelioid cells with large vesicular nuclei and prominent nucleoli (Reed-Sternberg-like cells or virocytes). The stroma was mostly fibrous and showed a polymorphous inflammatory infiltrate. Myxoid stromal changes were focally seen in one case, and pseudolipoblasts were absent. The immunophenotype was nonspecific, with only pan-keratin (AE1-AE3) and cyclin D1 expression in a subset of cases. RNA-Sequencing detected YAP1::MAML2 fusions in 3/7 cases; aCGH showed no significant gene copy number variations in 4 tested cases, and FISH analysis showed no VGLL3 amplification in 1 tested case. Follow-up was available for 6 cases, ranging from 7 to 63 months (median: 42 months). Local recurrence and metastasis were not seen and one tumor showed spontaneous regression following initial biopsy. In conclusion, we describe a novel variant of MIFS with distinctive clinicopathological and molecular features for which we propose the term "nodular necrotizing" MIFS., (© 2022. The Author(s), under exclusive licence to United States & Canadian Academy of Pathology.)

Purpose: Targeted therapies (TT) and immune checkpoint blockers (ICB) have revolutionized the approach to non-small cell lung cancer (NSCLC) treatment in the era of precision medicine. Their impact as switch maintenance therapy based on molecular characterization is unknown., Patients and Methods: SAFIR02-Lung/IFCT 1301 was an open-label, randomized, phase II trial, involving 33 centers in France. We investigated eight TT (substudy-1) and one ICB (substudy-2), compared with standard-of-care as a maintenance strategy in patients with advanced EGFR, ALK wild-type (wt) NSCLC without progression after first-line chemotherapy, based on high-throughput genome analysis. The primary outcome was progression-free survival (PFS)., Results: Among the 175 patients randomized in substudy-1, 116 received TT (selumetinib, vistusertib, capivasertib, AZD4547, AZD8931, vandetanib, olaparib, savolitinib) and 59 standard-of-care. Median PFS was 2.7 months [95% confidence interval (CI), 1.6-2.9] with TT versus 2.7 months (1.6-4.1) with standard-of-care (HR, 0.97; 95% CI, 0.7-1.36; P = 0.87). There were no significant differences in PFS within any molecular subgroup. In substudy-2, 183 patients were randomized, 121 received durvalumab and 62 standard-of-care. Median PFS was 3.0 months (2.3-4.4) with durvalumab versus 3.0 months (2.0-5.1) with standard-of-care (HR, 0.86; 95% CI, 0.62-1.20; P = 0.38). Preplanned subgroup analysis showed an enhanced benefit with durvalumab in patients with PD-L1 tumor proportion score (TPS) ≥1%, (n = 29; HR, 0.29; 95% CI, 0.11-0.75) as compared with PD-L1 <1% (n = 31; HR, 0.71; 95% CI, 0.31-1.60; Pinteraction = 0.036)., Conclusions: Molecular profiling can feasibly be implemented to guide treatment choice for the maintenance strategy in EGFR/ALK wt NSCLC; in this study it did not lead to substantial treatment benefits beyond durvalumab for PD-L1 ≥ 1 patients., (©2022 American Association for Cancer Research.)

Background: The high sensitivity of PET-CT can identify hypermetabolic mediastinal adenopathies during cancer management, but specificity is low and a biopsy is sometimes required to eliminate benign adenopathies., Methods: This prospective diagnostic accuracy study included patients with hypermetabolic mediastinal lymphadenopathies revealed on PET-CT during either the initial management of a cancer, treatment evaluation, or monitoring. All patients underwent EUS-FNA. Diagnoses of malignancy based on cytological analysis following EUS-FNA were compared with clinical and radiological follow-up information. The treatment strategy decided before the results of the EUS-FNA pathology reports (Multidisciplinary Team Meeting [MTM-1]) was recorded and compared to the treatment strategy decided once pathological data from EUS-FNA were available (MTM-2)., Main Findings: Between 2013 and 2018, 75 patients were included with 47 eligible and evaluable patients. Sensitivity, specificity, and positive and negative predictive values of EUS-FNA were 93%, 100%, 100% and 90%, respectively. The concordance value between the therapeutic strategies determined for MTM-1 and MTM-2 was 44.7%. There were no significant differences in the intensity of fixation on PET-CT between malignant and benign lesions., Conclusion: The diagnostic accuracy of the minimally invasive EUS-FNA procedure is sufficiently robust to avoid the need for diagnostic surgery. The combination of PET-CT and EUS-FNA may alter the therapeutic strategy that would be considered after PET-CT alone., Registration: NCT01892501., (Copyright © 2022 Elsevier Masson SAS. All rights reserved.)

Background: Tumor-associated macrophages (TAMs) having immunosuppressive properties are one of the most abundant immune cells in the tumor microenvironment (TME). Preclinical studies have highlighted the potential role of TAMs in resistance to immune checkpoint blockers (ICBs). Here, we investigated the predictive value of TAM infiltration in patients with non-small cell lung cancer (NSCLC) treated with ICBs and characterized their transcriptomic profiles., Methods: Tumor samples were collected from 152 patients with NSCLC before ICB treatment onset. After immunohistochemical staining and image analysis, the correlation between CD163+ cell infiltration and survival was analyzed. Spatial transcriptomic analyses were performed using the NanoString GeoMx Immune Pathways assay to compare the gene expression profile of tumors with high or low levels of CD163+ cell infiltration and to identify determinants of response to ICBs in tumors with high CD163+ infiltration., Results: Low intratumoral CD163+ cell infiltration was associated with longer progression-free survival (PFS; HR 0.61, 95% CI 0.40 to 0.94, p=0.023) and overall survival (OS; HR 0.48, 95% CI 0.28 to 0.80, p=0.004) under ICB treatment. Spatial transcriptomic profiles of 16 tumors revealed the upregulation of ITGAM , CD27, and CCL5 in tumors with high CD163+ cell infiltration. Moreover, in tumors with high macrophage infiltration, the upregulation of genes associated with the interferon-γ signaling pathway and the M1 phenotype was associated with better responses under immunotherapy. Surprisingly, we found also a significantly higher expression of CSF1R in the tumors of responders. Analysis of three independent data sets confirmed that high CSF1R expression was associated with an increased durable clinical benefit rate (47% vs 6%, p=0.004), PFS (median 10.89 months vs 1.67 months, p=0.001), and OS (median 23.11 months vs 2.66 months, p<0.001) under ICB treatment., Conclusions: Enrichment of TAMs in the TME of NSCLC is associated with resistance to immunotherapy regardless of the programmed death ligand 1 status and is driven by upregulation of CD27 , ITGAM, and CCL5 gene expression within the tumor compartment. Our transcriptomic analyses identify new potential targets to alter TAM recruitment/polarization and highlight the complexity of the CSF1R pathway, which may not be a suitable target to improve ICB efficacy., Competing Interests: Competing interests: ML, IS, SC, FLL: Nothing to disclose. AB, J-PG, CR: Employees of Explicyte. AI: Received research grants from AstraZeneca, Bayer, BMS, Chugai, Merck, MSD, Pharmamar, Novartis, Roche, and received personal fees from Epizyme, Bayer, Lilly, Roche, and Springworks. BB: Received grants from AstraZeneca, Pfizer, Eli Lilly, Onxeo, Bristol Myers Squibb, Inivata, AbbVie, Amgen, Blueprint Medicines, Celgene, GlaxoSmithKline, Ignyta, Ipsen, Merck KGaA, MSD Oncology, Nektar, PharmaMar, Sanofi, Spectrum Pharmaceuticals, Takeda, Tiziana Therapeutics, Cristal Therapeutics, Daiichi Sankyo, Janssen Oncology, OSE Immunotherapeutics, BeiGene, Boehringer Ingelheim, Genentech, Servier, Tolero Pharmaceuticals. J-CS: Has received consultancy fees from AstraZeneca, Astex, Clovis, GSK, GamaMabs, Lilly, MSD, Mission Therapeutics, Merus, Pfizer, Pharma Mar, Pierre Fabre, Roche/Genentech, Sanofi, Servier, Symphogen, and Takeda. FB: Has received consultancy fees from AstraZeneca, Astex, Clovis, GSK, GamaMabs, Lilly, MSD, Mission Therapeutics, Merus, Pfizer, Pharma Mar, Pierre Fabre, Roche/Genentech, Sanofi, Servier, Symphogen, and Takeda., (© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Introduction: Lymph node metastasis is determinant in the prognosis and treatment of endometrioid endometrial cancer (EEC) but the risk-benefit balance of surgical lymph node staging remains controversial., Objective: Describe the pathways associated with lymph node metastases in EEC detected by whole RNA sequencing., Methods: RNA-sequencing was performed on a retrospective series of 30 non-metastatic EEC. N+ and N- patients were matched for tumoral size, tumoral grade and myometrial invasion., Results: Twenty-eight EECs were analyzable (16 N+ and 12 N-). Bioinformatics Unsupervised analysis revealed three patterns of expression, enriched in N+, mix of N+/N- and enriched in N-, respectively. The cluster with only N+ patient overexpressed extra cellular matrix, epithelial to mesenchymal and smooth muscle contraction pathways with respect to the N- profile. Differential expression analysis between N+ and N- was used to generate a 54-genes signature with an 87% accuracy., Conclusion: RNA-expression analysis provides a basis to develop a gene expression-based signature that could pre-operatively predict lymph node invasion.

Background: Regorafenib has shown substantial clinical activity in patients with advanced biliary tract cancers (BTCs). Preclinical data suggested that this drug modulates antitumour immunity and is synergistic with immune checkpoint inhibition., Patients and Methods: This is a single-arm, multicentric phase II trial. Regorafenib was given 3 weeks/4, 160 mg quaque die (once a day) (QD); avelumab 10 mg/kg IV was given every two weeks, beginning at C1D15 until progression or unacceptable toxicity. The primary end-point was the confirmed objective response rate under treatment, as per Response Evaluation Criteria in Solid Tumours 1.1. The secondary end-points included the following: 1-year non-progression rate; progression-free survival (PFS) and overall survival; safety and biomarkers studies performed on sequential tumour samples obtained at baseline and at cycle 2 day 1., Results: Thirty-four patients were enrolled in four centres. Twenty-nine patients were assessable for efficacy after central radiological review. The best response was partial response for four patients (13.8%), stable disease for 11 patients (37.9%) and progressive disease for 14 patients (48.3%). The median PFS and overall survival were 2.5 months (95% confidence interval [CI] [1.9-5.5]) and 11.9 months (95%CI [6.2-NA]) respectively. The most common grade 3 or 4 clinical adverse events related to treatment were hypertension (17.6%), fatigue (14.7%) and maculopapular rash (11.8%). High baseline levels of programmed cell death ligand 1 and of indoleamine 2, 3-dioxygénase expression were associated with improved outcomes., Conclusions: Regorafenib combined with avelumab has antitumour activity in a subset of heavily pretreated biliary tract cancer population. Further investigations are needed in patients selected based on tumour microenvironment features., Clinical Trial Registration: NCT03475953., Competing Interests: Conflict of interest statement AB, CR and JPG: employees from Immusmol/Explicyte. AI: research grants MSD, BMS, ROCHE and personal fees: Epizyme, Bayer, Lilly, Roche, Springworks; non-financial support: Merck. All remaining authors have declared no conflicts of interest., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Background: The difficulty in interpreting somatic alterations is correlated with the increase in sequencing panel size. To correctly guide the clinical management of patients with cancer, there needs to be accurate classification of pathogenicity followed by actionability assessment. Here, we describe a specific detailed workflow for the classification of the pathogenicity of somatic variants in cancer into five categories: benign, likely benign, unknown significance, likely pathogenic and pathogenic., Methods: Classification is obtained by combining a set of eight relevant criteria in favour of either a pathogenic or a benign effect (pathogenic stand-alone, pathogenic very strong, pathogenic strong, pathogenic moderate, pathogenic supporting, benign supporting, benign strong and benign stand-alone)., Results: Our guide is concordant with the ACMG/AMP 2015 guidelines for germline variants. Interpretation of somatic variants requires considering specific criteria, such as the disease and therapeutic context, co-occurring genomic events in the tumour when available and the use of cancer-specific variant databases. In addition, the gene role in tumorigenesis (oncogene or tumour suppressor gene) also needs to be taken into consideration., Conclusion: Our classification could contribute to homogenize best practices on somatic variant pathogenicity interpretation and improve interpretation consistency both within and between laboratories., Competing Interests: Conflict of interest statement The authors declare no conflict of interest., (Copyright © 2021. Published by Elsevier Ltd.)

Background: Soft-tissue sarcomas (STS) represent a heterogeneous group of rare tumors including more than 70 different histological subtypes. High throughput molecular analysis (next generation sequencing exome [NGS]) is a unique opportunity to identify driver mutations that can change the usual one-size-fits-all treatment paradigm to a patient-driven therapeutic strategy. The primary objective of the MULTISARC trial is to assess whether NGS can be conducted for a large proportion of metastatic STS participants within a reasonable time, and, secondarily to determine whether a NGS-guided therapeutic strategy improves participant's outcome., Methods: This is a randomized, multicentre, phase II/III trial inspired by the design of umbrella and biomarker-driven trials. The setting plans up to 17 investigational centres across France and the recruitment of 960 participants. Participants aged at least 18 years, with unresectable locally advanced and/or metastatic STS confirmed by the French sarcoma pathological reference network, are randomized according to 1:1 allocation ratio between the experimental arm "NGS" and the standard "No NGS". NGS will be considered feasible if (i) NGS results are available and interpretable, and (ii) a report of exome sequencing including a clinical recommendation from a multidisciplinary tumor board is provided to investigators within 7 weeks from reception of the samples on the biopathological platform. A feasibility rate of more than 70% is expected (null hypothesis: 70% versus alternative hypothesis: 80%). In terms of care, participants randomized in "No NGS" arm and who fail treatment will be able to switch to the NGS arm at the request of the investigator., Discussion: The MULTISARC trial is a prospective study designed to provide high-level evidence to support the implementation of NGS in routine clinical practice for advanced STS participants, on a large scale., Trial Registration: clinicaltrial.gov NCT03784014 ., (© 2021. The Author(s).)

Aims: Superficial CD34-positive fibroblastic tumor (SCD34FT) and PRDM10-rearranged soft tissue tumor (PRDM10-STT) are rare mesenchymal tumors. These lesions have clinicopathological similarities, but their relationship remains controversial. This study aimed to characterise a series of cases of SCD34FT and PRDM10-STT., Methods and Results: Ten lesions each of SCD34FT and PRDM10-STT were studied using immunohistochemistry, array-comparative genomic hybridisation (aCGH), RNA sequencing and exome sequencing. Tumors mainly occurred in young adults, were generally small (< 5 cm) and arose predominantly in the superficial soft tissues of the lower extremities. Follow-up data were available in 15 cases (SCD34FT, n = 7, median 16 months; PRDM10-STT, n = 8, median 14 months), local recurrences occurred in four cases (SCD34FT, two of 10; PRDM10-STT, two of 10), while no distant spread was documented. Morphologically, tumors were relatively well-circumscribed and composed of sheets and fascicles of spindle and pleomorphic cells showing low mitotic activity (< 1/mm²) without necrosis. Other findings included: granular cell change, lipoblast-like cells, ectatic blood vessels with fibrinous material, myxoid stromal changes, metaplastic bone and increased mitotic activity (> 1/mm²). All tumors diffusely expressed CD34, while pan-keratin and desmin were commonly seen focally. SynCAM3 was diffusely expressed in 12 cases (SCD34FT, n = 5; PRDM10-STT, n = 7), independently of fusion status. aCGH profiles were 'flat' (PRDM10-STT, n = 4; SCD34FT, n = 2) and exome sequencing showed no recurrent pathogenic mutations (PRDM10-STT, n = 2; SCD34FT, n = 4). Overall, the only morphological features seen exclusively in PRDM10-STT were myxoid stromal changes (three of 10) and metaplastic bone (two of 10)., Conclusion: We expand the current knowledge on PRDM10-STT and SCD34FT and provide additional evidence for considering them as overlapping entities., (© 2021 John Wiley & Sons Ltd.)

Only a minority of patients derive long-term clinical benefit from anti-PD1/PD-L1 monoclonal antibodies. The presence of tertiary lymphoid structures (TLS) has been associated with improved survival in several tumor types. Here, using a large-scale retrospective analysis of three independent cohorts of cancer patients treated with anti-PD1/PD-L1 antibodies, we showed that the presence of mature TLS was associated with improved objective response rate, progression-free survival, and overall survival independently of PD-L1 expression status and CD8+ T-cell density. These results pave the way for using TLS detection to select patients who are more likely to benefit from immune checkpoint blockade., Competing Interests: DECLARATION OF INTERESTS LV, MB, SC, SLM, ML, IS, MT, GR, SP, MC, FC, CL, KB, MK, IG, CSF, VV, FC, WHF, and FLL: Nothing to disclose AB, JPG, and CR: Employees of Immusmol/Explicyte EO, AS: Employees of Astra Zeneca AI: Received research grants from Astra Zeneca, Bayer, BMS, Chugai, Merck, MSD, Pharmamar, Novartis, Roche, and received personal fees from Epizyme, Bayer, Lilly, Roche, and Springworks BB: Received grants from AstraZeneca , Pfizer , Eli Lilly , Onxeo , Bristol Myers Squibb , Inivata , Abbvie , Amgen , Blueprint Medicines , Celgene , GlaxoSmithKline , Ignyta , Ipsen , Merck KGaA , MSD Oncology , Nektar , PharmaMar , Sanofi , Spectrum Pharmaceuticals , Takeda , Tiziana Therapeutics , Cristal Therapeutics , Daiichi Sankyo , Janssen Oncology , OSE Immunotherapeutics , BeiGene , Boehringer Ingelheim , Genentech , SERVIER , Tolero Pharmaceuticals YL: Received grants and personal fees from Janssen, during the conduct of the study; personal fees and non-financial support from Astellas, grants and personal fees from Sanofi, personal fees and non-financial support from Roche, personal fees and non-financial support from AstraZeneca, grants, personal fees and non-financial support from MSD, personal fees and non-financial support from BMS, personal fees from Clovis , personal fees and non-financial support from Seattle Genetics, personal fees from Incyte, personal fees from Pfizer. AM: Received research grants from Mersu, Bristol-Myers Squibb, Boehringer Ingelheim, Transgene, MSD and received personal fees from Bristol-Myers Squibb, AstraZeneca, MedImmune, Oncovir, Merieux JCS: Has received consultancy fees from AstraZeneca, Astex, Clovis, GSK, GamaMabs, Lilly, MSD, Mission Therapeutics, Merus, Pfizer, Pharma Mar, Pierre Fabre, Roche/Genentech, Sanofi, Servier, Symphogen, and Takeda.

Human γδ T cells contribute to tissue homeostasis and participate in epithelial stress surveillance through mechanisms that are not well understood. Here, we identified ephrin type-A receptor 2 (EphA2) as a stress antigen recognized by a human Vγ9Vδ1 TCR. EphA2 is recognized coordinately by ephrin A to enable γδ TCR activation. We identified a putative TCR binding site on the ligand-binding domain of EphA2 that was distinct from the ephrin A binding site. Expression of EphA2 was up-regulated upon AMP-activated protein kinase (AMPK)-dependent metabolic reprogramming of cancer cells, and coexpression of EphA2 and active AMPK in tumors was associated with higher CD3 T cell infiltration in human colorectal cancer tissue. These results highlight the potential of the human γδ TCR to cooperate with a co-receptor to recognize non-MHC-encoded proteins as signals of cellular dysregulation, potentially allowing γδ T cells to sense metabolic energy changes associated with either viral infection or cancer., (Copyright © 2021 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)

Background: PAOLA1 is a phase III study assessing olaparib maintenance therapy in advanced high-grade ovarian carcinoma patients responding to first-line platinum-taxane-based chemotherapy plus bevacizumab as standard of care. Randomization was stratified by treatment outcome and tumor BRCA1/2 status (tBRCA) at screening., Methods: tBRCA was tested on formalin-fixed, paraffin-embedded tumor blocks on 5 French platforms using 2 next-generation sequencing methods based either on hybrid capture or amplicon technology. One of the exploratory objectives was to assess the concordance between germline (gBRCA) and tBRCA testing in French patients. gBRCA testing was performed on blood samples on the same platforms., Results: From May 2015 to July 2017, tBRCA tests were performed for 1176 screened patients. Only 52 (4.4%) tumor samples were noncontributive. The median interval between reception of the tumor sample and availability of the tBRCA status result was 37 days (range = 8-260). A pathogenic variant was reported in 27.1% tumor samples (319 of 1176 screened patients). tBRCA and gBRCA testing were performed for 451 French patients with negative results for both tests in 306 patients (67.8%) and positive results for both tests in 85 patients (18.8%). Only 1 large genomic rearrangement of BRCA1 was detected, exclusively in the blood sample. Interestingly, tBRCA testing revealed 6.4% of pathogenic variant (29 of 451) not detected by gBRCA testing., Conclusions: tBRCA testing is an appropriate tool with an acceptable turnaround time for clinical practice and a low failure rate, ensuring reliable identification of patients likely to benefit from poly(ADP-ribose) polymerase inhibitor therapy., (© The Author(s) 2020. Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Activating mutations of MYD88 ( MYD88 L265P being the far most frequent) are found in most cases of Waldenström macroglobulinemia (WM) as well as in various aggressive B-cell lymphoma entities with features of plasma cell (PC) differentiation, such as activated B-cell type diffuse large B-cell lymphoma (DLBCL). To understand how MYD88 activation exerts its transformation potential, we developed a new mouse model in which the MYD88 L252P protein, the murine ortholog of human MYD88 L265P , is continuously expressed in CD19 positive B-cells together with the Yellow Fluorescent Protein (Myd88 L252P mice). In bone marrow, IgM B and plasma cells were expanded with a CD138 expression continuum from IgM high CD138 low to IgM low CD138 high cells and the progressive loss of the B220 marker. Serum protein electrophoresis (SPE) longitudinal analysis of 40 Myd88 L252P mice (16 to 56 weeks old) demonstrated that ageing was first associated with serum polyclonal hyper gammaglobulinemia (hyper Ig) and followed by a monoclonal immunoglobulin (Ig) peak related to a progressive increase in IgM serum levels. All Myd88 L252P mice exhibited spleen enlargement which was directly correlated with the SPE profile and was maximal for monoclonal Ig peaks. Myd88 L252P mice exhibited very early increased IgM PC differentiation. Most likely due to an early increase in the Ki67 proliferation index, IgM lymphoplasmacytic (LP) and plasma cells continuously expanded with age being first associated with hyper Ig and then with monoclonal Ig peak. This peak was consistently associated with a spleen LP-like B-cell lymphoma. Clonal expression of both membrane and secreted µ chain isoforms was demonstrated at the mRNA level by high throughput sequencing. The Myd88 L252P tumor transcriptomic signature identified both proliferation and canonical NF-κB p65/RelA activation. Comparison with MYD88 L265P WM showed that Myd88 L252P tumors also shared the typical lymphoplasmacytic transcriptomic signature of WM bone marrow purified tumor B-cells. Altogether these results demonstrate for the first time that continuous MYD88 activation is specifically associated with clonal transformation of differentiating IgM B-cells. Since MYD88 L252P targets the IgM PC differentiation continuum, it provides an interesting preclinical model for development of new therapeutic approaches to both WM and aggressive MYD88 associated DLBCLs., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Ouk, Roland, Gachard, Poulain, Oblet, Rizzo, Saintamand, Lemasson, Carrion, Thomas, Balabanian, Espéli, Parrens, Soubeyran, Boulin, Faumont, Feuillard and Vincent-Fabert.)

Purpose: Regorafenib is synergistic with immune checkpoint inhibition in colorectal cancer preclinical models., Patients and Methods: This was a single-arm, multicentric phase II trial. Regorafenib was given 3 weeks on/1 week off, 160 mg every day; avelumab 10 mg/kg i.v. was given every 2 weeks, beginning at cycle 1, day 15 until progression or unacceptable toxicity. The primary endpoint was the confirmed objective response rate under treatment, as per RECIST 1.1. The secondary endpoints included a 1-year nonprogression rate, progression-free survival (PFS), and overall survival (OS), safety and biomarkers studies performed on sequential tumor samples obtained at baseline and at cycle 2 day 1., Results: Forty-eight patients were enrolled in four centers. Forty-three were assessable for efficacy after central radiological review. Best response was stable disease for 23 patients (53.5%) and progressive disease for 17 patients (39.5%). The median PFS and OS were 3.6 months [95% confidence interval (CI), 1.8-5.4] and 10.8 months (95% CI, 5.9-NA), respectively. The most common grade 3 or 4 adverse events were palmar-plantar erythrodysesthesia syndrome ( n = 14, 30%), hypertension ( n = 11, 23%), and diarrhea ( n = 6, 13%). High baseline infiltration by tumor-associated macrophages was significantly associated with adverse PFS (1.8 vs. 3.7 months; P = 0.002) and OS (3.7 months vs. not reached; P = 0.002). Increased tumor infiltration by CD8 + T cells at cycle 2, day 1 as compared with baseline was significantly associated with better outcome., Conclusions: The combination of regorafenib + avelumab mobilizes antitumor immunity in a subset of patients with microsatellite stable colorectal cancer. Computational pathology through quantification of immune cell infiltration may improve patient selection for further studies investigating this approach., (©2021 American Association for Cancer Research.)

Despite survival improvements achieved over the last two decades, prostate cancer remains lethal at the metastatic castration-resistant stage (mCRPC) and new therapeutic approaches are needed. Germinal and/or somatic alterations of DNA-damage response pathway genes are found in a substantial number of patients with advanced prostate cancers, mainly of poor prognosis. Such alterations induce a dependency for single strand break reparation through the poly(adenosine diphosphate-ribose) polymerase (PARP) system, providing the rationale to develop PARP inhibitors. In solid tumors, the first demonstration of an improvement in overall survival was provided by olaparib in patients with mCRPC harboring homologous recombination repair deficiencies. Although this represents a major milestone, a number of issues relating to PARP inhibitors remain. This timely review synthesizes and discusses the rationale and development of PARP inhibitors, biomarker-based approaches associated and the future challenges related to their prescription as well as patient pathways.