Search

Background Successfully combining targeted agents with chemotherapy is an important future goal for cancer therapy. However, an improvement in patient outcomes requires an enhanced understanding of the tumor biomarkers that predict for drug sensitivity. NRG Oncology/Gynecologic Oncology Group (GOG) Study GOG-86P was one of the first attempts to combine targeted agents (bevacizumab or temsirolimus) with chemotherapy in patients with advanced endometrial cancer. Herein we performed exploratory analyses to examine the relationship between mutations in TP53, the most commonly mutated gene in cancer, with outcomes on GOG-86P. Methods TP53 mutational status was determined and correlated with progression-free survival (PFS) and overall survival (OS) on GOG-86P. Results Mutations in TP53 were associated with improved PFS and OS for patients that received bevacizumab as compared to temsirolimus (PFS: HR 0.48, 95% CI 0.31, 0.75; OS: HR: 0.61, 95% CI 0.38, 0.98). By contrast, there was no statistically significant difference in PFS or OS between arms for cases with WT TP53. Conclusions This exploratory study suggests that combining chemotherapy with bevacizumab, but not temsirolimus, may enhance PFS and OS for patients whose tumors harbor mutant p53. These data set the stage for larger clinical studies evaluating the potential of TP53 mutational status as a biomarker to guide choice of treatment for endometrial cancer patients. Clintrials.gov : NCT00977574 .

Purpose: A phase I clinical trial (GOG-9929) examined the safety and efficacy of adjuvant immune-modulation therapy with the checkpoint inhibitor ipilimumab [anti–CTL antigen-4 (anti–CTLA-4)] following chemoradiation therapy (CRT) for newly diagnosed node-positive human papillomavirus (HPV)-related cervical cancer. To better understand the mechanism of action and to identify predictive biomarkers, immunologic and viral correlates were assessed before, during, and after treatment. Patients and Methods: Twenty-one patients who received CRT and ≥2 doses of ipilimumab and 5 patients who received CRT only were evaluable for translational endpoints. Circulating T-cell subsets were evaluated by multiparameter flow cytometry. Cytokines were evaluated by multiplex ELISA. HPV-specific T cells were evaluated in a subset of patients by IFNγ ELISpot. Results: Expression of the activation markers ICOS and PD-1 significantly increased on T-cell subsets following CRT and were sustained or increased following ipilimumab treatment. Combined CRT/ipilimumab treatment resulted in a significant expansion of both central and effector memory T-cell populations. Genotype-specific E6/E7-specific T-cell responses increased post-CRT in 1 of 8 HPV16+ patients and in 2 of 3 HPV18+ patients. Elevation in levels of tumor-promoting circulating cytokines (TNFα, IL6, IL8) post-CRT was significantly associated with worse progression-free survival. Conclusions: Our data indicate that CRT alone and combined with ipilimumab immunotherapy show immune-modulating activity in women with locally advanced cervical cancer and may be a promising therapeutic option for the enhancement of antitumor immune cell function after primary CRT for this population at high risk for recurrence and metastasis. Several key immune biomarkers were identified that were associated with clinical response.

Background Immune checkpoint inhibitors are being considered for locally advanced cervical cancer (LACC) together with standard-of-care pelvic chemoradiation (CRT). However, the safety of the combination and its optimal schedule are unknown. Defining the safety of the combination is a primary objective of a study examining concurrent and sequential schedules. This article presents a safety analysis that was fully accrued and met reporting requirements. Methods Pembrolizumab was given after CRT (arm 1) or during CRT (arm 2) according to a randomized phase 2 design. Patients who were 18 years old or older and had LACC (stages IB-IVA according to the 2009 International Federation of Gynecology and Obstetrics system) were randomized 1:1 to the treatment regimens. The CRT was identical in the 2 arms. Pembrolizumab was administered every 3 weeks for 3 doses; no maintenance was allowed. All patients receiving any treatment were evaluated for safety. Safety assessments included the incidence and severity of adverse events (AEs) and the occurrence of protocol-defined dose-limiting toxicity (DLT) through 30 days after the last pembrolizumab infusion. Results As of August 2019, 52 of the 88 planned patients had completed treatment and were evaluable for toxicity. Treatment-related grade 2 or higher toxicity was experienced by 88%; 11 had at least 1 grade 4 AE, and another 23 had at least 1 grade 3 AE. Grade 1 or higher diarrhea was reported in 34 patients (65%; 50% of these were grade 1), and there was no difference between arms (63% in arm 1 vs 68% in arm 2). Two patients experienced 3 DLTs. Most patients completed cisplatin (100% in arm 1 vs 82% in arm 2); 83% in both arms completed all pembrolizumab. Conclusions Preliminary results support the safety and feasibility of adding pembrolizumab to pelvic CRT concurrently or sequentially. Lay summary Pembrolizumab is a humanized antibody against programmed cell death protein 1 that is used in cancer immunotherapy. Preliminary data suggest that pembrolizumab can be safely combined with chemotherapy and pelvic radiation in the treatment of locally advanced cervical cancer. Future studies of the addition of immunotherapy to traditional chemoradiation are planned to determine the best way to deliver the treatment and whether any improvement is seen with the addition of immunotherapy to traditional therapy.

BACKGROUND: Stage III or IVA endometrial cancer carries a significant risk of systemic and locoregional recurrence. METHODS: In this randomized phase 3 trial, we tested whether 6 months of platinum-based chemotherapy plus radiation therapy (chemoradiotherapy) is associated with longer relapse-free survival (primary end point) than six cycles of combination chemotherapy alone in patients with stage III or IVA endometrial carcinoma. Secondary end points included overall survival, acute and chronic toxic effects, and quality of life. RESULTS: Of the 813 patients enrolled, 736 were eligible and were included in the analysis of relapse-free survival; of those patients, 707 received the randomly assigned intervention (346 received chemoradiotherapy and 361 received chemotherapy only). The median follow-up period was 47 months. At 60 months, the Kaplan–Meier estimate of the percentage of patients alive and relapse-free was 59% (95% confidence interval [CI], 53 to 65) in the chemoradiotherapy group and 58% (95% CI, 53 to 64) in the chemotherapy-only group (hazard ratio, 0.90; 90% CI, 0.74 to 1.10). Chemoradiotherapy was associated with a lower 5-year incidence of vaginal recurrence (2% vs. 7%; hazard ratio, 0.36; 95% CI, 0.16 to 0.82) and pelvic and paraaortic lymph-node recurrence (11% vs. 20%; hazard ratio, 0.43; 95% CI, 0.28 to 0.66) than chemotherapy alone, but distant recurrence was more common in association with chemoradiotherapy (27% vs. 21%; hazard ratio, 1.36; 95% CI, 1.00 to 1.86). Grade 3, 4, or 5 adverse events were reported in 202 patients (58%) in the chemoradiotherapy group and 227 patients (63%) in the chemotherapy-only group. CONCLUSIONS: Chemotherapy plus radiation was not associated with longer relapse-free survival than chemotherapy alone in patients with stage III or IVA endometrial carcinoma. (Funded by the National Cancer Institute; ClinicalTrials.gov number, NCT00942357.)

Objectives: Although primary results from the IMagyn050 trial showed no statistically significant improvement in progression-free survival (PFS) with atezo added to carboplatin/paclitaxel/bevacizumab (CPB) [Moore, ESMO 2020], the impact of this regimen on selected patient (pt)-reported ovarian cancer symptoms, function, and health-related quality of life (HRQoL) is unknown and the focus of this study. Methods: IMagyn050 is a double-blind randomized phase 3 trial evaluating the efficacy and safety of adding atezo/placebo to CPB followed by maintenance bevacizumab + atezo/placebo. The trial includes two cohorts: neoadjuvant chemotherapy (NACT) and primary surgery (PS). Pts complete EORTC QLQ-C30, QLQ-OV28, and FACT-G single-item GP5 at baseline (BL) and at regular intervals during treatment and follow-up. In NACT pts, prespecified responder analyses (using a ≥10-point cutoff for clinically meaningful change) assessed improvement in abdominal pain (OV28 item 31) and bloating (OV28 item 32) at week 9, comparing treatment arms by Cochran-Mantel-Haenszel (CMH) testing. Additional secondary objectives in the NACT and PS cohorts were assessments of function (physical, role, emotional, social) and HRQoL, as measured by QLQ-C30 functional and global health status/quality of life scales. Exploratory endpoints included mean change from BL in symptoms (QLQ-C30 and OV28) and treatment side-effect bother (FACT-G GP5) in both cohorts. Results: Of 1301 randomized pts, completion rates for each of the 3 questionnaires were 83-100% at BL and >85% on treatment. In NACT pts, mean BL scores were similar in the atezo vs placebo arms for abdominal pain (40.2 vs 44.8) and bloating (50.4 vs 56.3). At week 9, there was no difference between treatments in the proportion of NACT pts with ≥10-point improvement in either symptom (abdominal pain: 69/136 [51%] with atezo vs 77/142 [54%] with placebo, CMH p=0.56; bloating: 74 [54%] vs 89 [63%], CMH p=0.14). Results were consistent when restricted to NACT pts with sufficient BL symptoms to show ≥10-point improvement. There was no difference between treatments in the proportion of NACT pts with improvement in function or HRQoL at week 9. In the PS cohort, similar proportions of pts in each arm showed on-treatment improvement, stabilization, or deterioration in function and HRQoL. In both cohorts, neither arm showed meaningful changes from BL in treatment-related symptoms and similar proportions of pts in both arms reported being ‘a little bit’ or ‘somewhat’ bothered by treatment side effects while on therapy. Conclusions: Consistent with PFS results, there were no differences between arms in the proportion of NACT pts with a clinically meaningful improvement in abdominal pain and bloating after 3 cycles of bevacizumab-containing therapy. Pt-reported outcome analyses in both cohorts showed that adding atezo to CPB did not increase treatment burden for pts, thereby demonstrating the tolerability of this 4-drug regimen and providing further insight on the benefit-risk assessment of atezo.

Background Management of advanced endometrial cancer after failure with platinum therapy remains a challenge. Tumors characterized by DNA repair abnormalities are associated with high numbers of neoantigens; immunotherapy is promising in this setting as demonstrated in studies with checkpoint inhibitors (CPI). 1–6 Overcoming emerging resistance to CPI through novel combinations is a focus of research. Retifanlimab is an investigational humanized immunoglobulin G4 monoclonal antibody against programmed cell death 1 (PD 1). In POD1UM-101, retifanlimab monotherapy demonstrated acceptable tolerability and durable clinical benefit in multiple advanced tumor types, including pretreated endometrial cancer.7 POD1UM-204 is designed to further investigate efficacy and safety of retifanlimab alone or in combination with other immunotherapy or targeted agents in patients with advanced/metastatic endometrial cancer. Methods POD1UM-204 is a phase 2, multicenter, nonrandomized, open-label, umbrella study in women =18 years of age, with histologically confirmed diagnosis of advanced/metastatic endometrial cancer that has progressed on or after platinum-based chemotherapy. Patients must have an ECOG performance status =1, at least 1 measurable tumor lesion by Response Evaluation Criteria in Solid Tumors v1.1, and provide tumor tissue at baseline.Approximately 220 patients will be enrolled into 4 treatment groups: Group A–patients with MSI-H (microsatellite instability high) endometrial cancer and no prior CPI therapy (up to 100 patients) receiving retifanlimab monotherapy; Group B–patients with dMMR (deficient DNA mismatch repair) or POLE (DNA polymerase epsilon) endometrial cancer and no prior CPI therapy (up to 40 patients) receiving retifanlimab monotherapy; Group C–patients with unselected endometrial cancer and regardless of prior CPI treatment (up to 40 patients) receiving retifanlimab plus epacadostat (indoleamine 2,3-dioxygenase inhibitor); and Group D–patients with endometrial cancer and activating fibroblast growth factor receptor (FGFR1, 2 or 3) mutations or alterations outside of the kinase domain and regardless of prior CPI treatment (up to 40 patients) receiving retifanlimab plus pemigatinib (FGFR1, 2, 3 inhibitor) (figure 1). Patients can receive up to 26 treatment cycles if they continue to derive benefit and have not met criteria for withdrawal.The primary study objective is evaluating retifanlimab monotherapy antitumor activity (objective response rate [ORR] determined by independent central review [ICR]) in Group A. Secondary study objectives include assessing additional efficacy measures (duration of response, disease control rate and progression-free survival by ICR, and overall survival) in Group A; determining clinical activity (ORR by the investigator) in Groups B, C and D; and evaluating safety and tolerability of retifanlimab. Results N/A Conclusions N/A Acknowledgements This study is sponsored by Incyte Corporation (Wilmington, DE). Trial Registration ClinicalTrials. gov Identifier: NCT04463771; EudraCT 2020-000496-20 Ethics Approval The study was approved by institutional review boards or independent ethics committees of participating institutions. Consent N/A References Mittica G, Ghisoni E, Giannone G, et al. Checkpoint inhibitors in endometrial cancer: preclinical rationale and clinical activity. Oncotarget 2017;8:90532–544. Di Tucci C, Capone C, Galati G, et al. Immunotherapy in endometrial cancer: new scenarios on the horizon. J Gynecol Oncol 2019;30:e46. Brooks R, Fleming G, Lastra R, et al. Current recommendations and recent progress in endometrial cancer. CA Cancer J Clin 2019;69:258–79. Makker V, Rasco D, Vogelzang N, et al. Lenvatinib plus pembrolizumab in patients with advanced endometrial cancer: an interim analysis of a multicentre, open-label, single-arm, phase 2 trial. Lancet Oncol 2019;20:711–8. Marabelle A, Le D, Ascierto P, et al. Efficacy of Pembrolizumab in patients with noncolorectal high microsatellite instability/mismatch repair–deficient cancer: results from the phase II KEYNOTE-158 study. J Clin Oncol 2020;38:1–10. Oaknin, A, Duska L, Sullivan R, et al. Preliminary safety, efficacy, and pharmacokinetic/pharmacodynamic characterization from GARNET, a phase I/II clinical trial of the anti–PD-1 monoclonal antibody, TSR-042, in patients with recurrent or advanced MSI-h and MSS endometrial cancer. Gynecol Oncol 2019;154(suppl 1):17 [Abstract 33]. Mehnert JM, Joshua AM, Lakhani N, et al. First-in-human phase 1 study of INCMGA00012 in patients with advanced solid tumors: interim results of the cohort expansion phase. J Immunother Cancer 2018;6(suppl 1):115 [Abstract P669].

Purpose We conducted a randomized phase III trial to determine whether adjuvant chemotherapy improves survival in women with uterine leiomyosarcoma. Methods Women with uterus-confined, high-grade leiomyosarcoma who were confirmed disease free by imaging were randomly assigned to four cycles of gemcitabine plus docetaxel, followed by four cycles of doxorubicin, or to observation. All were followed for evidence of recurrence. The primary end point was overall survival (OS). Results With international collaboration, 38 of the targeted accrual of 216 patients were enrolled, after which the study was closed by the National Cancer Institute for accrual futility. Twenty patients were assigned to chemotherapy, 18 to observation. Among the 17 patients treated with at least one cycle of chemotherapy, grade 3 or 4 toxicities were observed in 47%; among the 18 patients assigned to observation, one had grade 3 hypertension. There were six deaths (chemotherapy, n = 5; observation, n = 1), all due to disease. The restricted mean survival time for OS was estimated as 34.3 months (95% CI, 25.3 to 43.3 months) in the chemotherapy arm and as 46.4 months (95% CI, 43.6 to 49.1 months) in the observation arm. There were eight recurrences in each arm. The restricted mean survival time for recurrence-free survival was estimated as 18.1 (95% CI, 14.2 to 22.0) months in the chemotherapy arm and as 14.6 months (95% CI, 10.3 to 19.0 months) in the observation arm. Neither survival outcome comparison was considered statistically robust, due to the small sample size. Conclusion Despite international collaboration to test the role of adjuvant chemotherapy in uterine-confined leiomyosarcoma, this study was closed for accrual futility. Although the sample size precludes robust statistical comparison, observed OS and recurrence-free survival data do not show superior outcomes with adjuvant chemotherapy.

Objective To assess whether the addition of oncolytic reovirus (Reolysin®) to weekly paclitaxel prolonged progression-free survival (PFS) in the treatment of women with recurrent or persistent ovarian, tubal or primary peritoneal cancer. Patients and methods Patients with recurrent or persistent epithelial ovarian, tubal, or peritoneal carcinoma, measurable or detectable disease, and three or fewer prior regimens were randomly assigned to paclitaxel (80mg/m 2 intravenously days 1, 8, and 15 every 4weeks) or the combination of paclitaxel (80mg/m 2 intravenously days 1, 8, and 15) plus reovirus 3×10 10 TCID 50 /day intravenously on days 1–5, both every 4weeks until disease progression or toxicity. The primary end point was PFS. The study was designed with 80% power for a one-sided alternative at a 10% level of significance to detect a reduction in the hazard by 37.5%. Results The study accrued 108 patients, 100 of whom were evaluable for toxicity. Median PFS was 4.3months for paclitaxel and 4.4months for paclitaxel plus reovirus (hazard ratio, 1.11; 90% two-sided CI, 0.78 to 1.59; one-sided P=0.687). The proportion responding (overall response rate) to paclitaxel was 20% among 45 patients with measurable disease receiving paclitaxel alone, and 17.4% among the 46 patients treated with the combination. The asymptotic relative probability of responding was 0.87 (90% CI, 0.42 to 1.79). Severe adverse events were more common in the combination regimen than in paclitaxel arm for severe neutropenia (grade≥4, 12% versus 0%), and severe respiratory adverse events (grade≥3, 25% versus 2%). No deaths were considered treatment related. Conclusion The addition of reovirus to weekly paclitaxel in the treatment of women with recurrent or persistent ovarian, tubal or peritoneal cancer did not sufficiently reduce the hazard of progression or death to warrant further investigation.

Objectives The ability to stratify a patient's risk of metastasis and survival permits more refined care. A proof of principle study was undertaken to investigate the relationship between single nucleotide polymorphisms (SNPs) in literature based candidate cancer genes and the risk of nodal metastasis and clinical outcome in endometrioid endometrial cancer (EEC) patients. Methods Surgically-staged EEC patients from the Gynecologic Oncology Group or Washington University School of Medicine with germline DNA available were eligible. Fifty-four genes represented by 384 SNPs, were evaluated by Illumina Custom GoldenGate array. Association with lymph node metastases was the primary outcome. Progression-free survival (PFS) and overall survival (OS) was also evaluated. Results 361 SNPs with high quality genotype data were evaluated in 337 patients with outcome data. Five SNPs in CXCR2 had an odds ratio (OR) between 0.68 and 0.70 (p-value ≤ 0.025). The A allele rs946486 in ABL had an OR of 1.5 (p-value = 0.01) for metastasis. The G allele in rs7795743 in EGFR had an OR for metastasis of 0.68 (p-value = 0.02) and hazard ratio (HR) for progression of 0.66 (p-value = 0.004). Importantly, no SNP met genome wide significance after adjusting for multiple test correcting and clinical covariates. The A allele in rs2159359 SNP in NME1 and the G allele in rs13222385 in EGFR were associated with worse OS. Both exhibited genome wide significance; rs13222385 remained significant after adjusting for prognostic clinical variables. Conclusion SNPs in cancer genes including rs2159359 SNP in NME1 and rs13222385 in EGFR may stratify risk in EEC and are prioritized for further investigation.

5527 Background: Treatment options for patients with recurrent cervical and endometrial cancer remain limited. Even with optimum care, median survival has stalled at 12-17 months. The PARP inhibitor rucaparib has demonstrated activity in both BRCA wild-type and mutant cancers. Furthermore, preclinical studies suggest a synergistic effect of PARP inhibitors and antiangiogenic agents. We hypothesized that the combination of rucaparib and the VEGF inhibitor bevacizumab would yield a clinically-significant anti-cancer effect in patients with persistent or recurrent cervical or endometrial carcinoma. Methods: NCT03476798 is a phase II trial of adults with histologically-documented carcinoma of the cervix or endometrium. Patients with evaluable lesions who had undergone at least one prior line of systemic therapy, had adequate performance status and organ function, with a life expectancy of at least three months were eligible. Biopsies were obtained prior to treatment initiation for assessment of baseline tumor biomarkers, including ARID1A mutation status. Each cycle comprised 21 days. Rucaparib was administered orally at 600 mg, twice daily. Bevacizumab was administered by IV at 15 mg/kg on day 1 of each cycle. The primary objective was to estimate the proportion of patients with persistent or recurrent cervical or endometrial cancer who survive progression-free for at least six months (PFS6). Kaplan-Meier analysis was used to estimate progression-free survival. Results: There were 28 evaluable patients; six had cervical and 22 had endometrial cancer. Median age was 60.5 years (range, 30-74). Self-reported patient races were White (82.1%), Black (10.7%), and Native American (7.1%). Self-identified Hispanic or Latina patients comprised 3.6% of the cohort. Twenty-two of 28 patients had progressive disease by six months [survival distribution function estimate = 0.214 (lower CI, 0.087; upper CI, 0.378)]. Of the six patients who achieved PFS6, one had cervical and five had endometrial cancer. Six patients had a mutation in the ARID1A gene and those patients achieved PFS6 at a rate of 66.7%. Conclusions: The study hypothesis was evaluated in a two-stage design, and the interim analysis occurred once 28 evaluable patients were enrolled. In order to move on to the second stage, at least seven patients needed to remain progression-free at six months, but only six did. Thus, the study was ended after the interim analysis. The combination of rucaparib and bevacizumab did not provide the expected clinical benefit in this cohort of patients, but may warrant further exploration in patients with ARID1A mutations. Clinical trial information: NCT03476798.

Short-form Ron (sfRon) is an understudied, alternative isoform of the full-length Ron receptor tyrosine kinase. In contrast to Ron, which has been shown to be an important player in many cancers, little is known about the role of sfRon in cancer pathogenesis. Here we report the striking discovery that sfRon expression is required for development of carcinogen-induced malignant ovarian tumors in mice. We also show that sfRon is expressed in several subtypes of human ovarian cancer including high-grade serous carcinomas, which is in contrast to no detectable expression in healthy ovaries. In addition, we report that introduction of sfRon into OVCAR3 cells resulted in epithelial-to-mesenchymal transition, activation of the PI3K and PDK1 pathway, and inhibition of the MAPK pathway. We demonstrated that sfRon confers an aggressive cancer phenotype in vitro characterized by increased proliferation and migration, and decreased adhesion of ovarian cancer cells. Moreover, the in vivo studies show that OVCAR3 tumors expressing sfRon exhibit significantly more robust growth and spreading to the abdominal cavity when compared with the parental sfRon negative OVCAR3 cells. These data suggest that sfRon plays a significant role in ovarian cancer initiation and progression, and may represent a promising therapeutic target for ovarian cancer treatment.

6003 Background: Combination cediranib (C) and olaparib (O) improved progression-free survival (PFS) in patients (pts) with relapsed platinum (plat)-sensitive high-grade ovarian cancer (ovca) compared to O alone in a Phase 2 trial (NCT01116648). We conducted this randomized, open-label Phase 3 trial (NCT02446600) to assess whether combination C+O, or O alone, was superior to standard of care (SOC) plat-based therapy in relapsed plat-sensitive ovca. Methods: Eligible pts had recurrent plat-sensitive [ > 6-month plat-free interval (PFI)] high-grade serous or endometrioid, or BRCA-related, ovca. One prior non-plat therapy and unlimited prior plat-therapies were allowed; prior anti-angiogenics in the recurrent setting or prior PARP inhibitor were exclusions. Pts were randomized 1:1:1 to SOC (carboplatin/paclitaxel; carboplatin/gemcitabine; or carboplatin/liposomal doxorubicin), O (300mg twice daily), or C+O (C 30mg daily + O 200mg twice daily). Randomization was stratified by g BRCA status, PFI (6-12 vs > 12 months), and prior anti-angiogenic therapy. Target sample size was 549 pts; primary analysis occurred 2 years after the last pt enrolled. The primary endpoint was PFS. Type 1 error = 0.025 was controlled by a gatekeeping hierarchy that assessed C+O vs SOC, then O alone vs SOC, and finally C+O vs O. All maintenance therapy was prohibited. Results: Between 4FEB2016 and 13NOV2017, 565 pts enrolled (187 SOC, 189 O, 189 C+O), and 528 pts initiated treatment (166 SOC, 183 O, 179 C+O). 23.7% of patients had g BRCAmut. Median follow-up was 29.1 months. 53 pts on SOC initiated non-protocol therapy (predominantly PARP inhibitor maintenance) before disease progression. The hazard ratio (HR) for PFS was 0.856 (95% CI 0.66-1.11, p = 0.08, 1-tail) between C+O and SOC and 1.20 (95% CI 0.93-1.54) between O and SOC, with median PFS of 10.3, 8.2, and 10.4 months for SOC, O, and C+O, respectively. Response rates were 71.3% (SOC), 52.4% (O), and 69.4% (C+O). In gBRCA pts, HR for PFS was 0.55 (95% CI 0.73-1.30) for C+O vs SOC, and 0.63 (95% CI 0.37-1.07) for O vs SOC. In non-g BRCA pts, HR for these comparisons was 0.97 (95% CI 0.73-1.30) and 1.41 (1.07-1.86). No OS differences between arms were observed at 44% events. Pts receiving C+O (vs SOC) had more frequent Grade 3 or higher gastrointestinal (30.1% vs 8.4%), hypertension (31.7% vs 1.8%), and fatigue events (17.5% vs 1.8%). Conclusion: C+O demonstrated similar activity to SOC in relapsed plat-sensitive ovca but did not meet the primary endpoint of improved PFS. Clinical trial information: NCT02446600.

Objective Preclinical data suggest elesclomol increases oxidative stress and enhances sensitivity to cytotoxic agents. The objective of this prospective multicenter phase 2 trial was to estimate the activity of IV elesclomol plus weekly paclitaxel in patients with platinum-resistant recurrent ovarian, tubal or peritoneal cancer through the frequency of objective tumor responses (ORR). Methods Patients with measurable disease, acceptable organ function, performance status ≤ 2, and one prior platinum containing regimen were eligible. A two-stage design was utilized with a target sample size of 22 and 30 subjects, respectively. Prior Gynecologic Oncology Group studies within the same population involving single agent taxanes showed an ORR of approximately (20%) and served as a historical control for direct comparison. The present study was designed to determine if the regimen had an ORR of ≥40% with 90% power. Results Fifty-eight patients were enrolled, of whom 2 received no study treatment and were inevaluable. The median number of cycles was 3 (268 total cycles, range 1–18). The number of patients responding was 11 (19.6%; 90% CI 11.4% to 30.4%) with one complete response. The median progression-free survival and overall survival was 3.6 months and 13.3 months, respectively. The median ORR duration was 9.2 months. Percentages of subjects with grade 3 toxicity included: Neutropenia 9%; anemia 5%; metabolic 5%; nausea 4%; infection 4%; neurologic (mostly neuropathy) 4%; and vascular (mostly thromboembolism) 4%. There were no grade 4 toxicities reported. Conclusions This combination was well tolerated but is unworthy of further investigation based on the proportion responding [ ClinicalTrials.gov Identifier: NCT00888615 ].

Objective This two-stage phase II study assessed activity of single agent dalantercept in patients with recurrent/persistent endometrial carcinoma (EMC). Methods Eligible patients had persistent/recurrent EMC after 1–2 prior cytotoxic regimens, measurable disease (RECIST 1.1), and GOG performance≤2. Dalantercept 1.2mg/kg subcutaneous was administered once every 3weeks until disease progression (PD)/development of prohibitory toxicity. Primary objectives were to estimate the proportion of patients with persistent/recurrent EMC, who survive progression-free without receiving non-protocol therapy (TPFS) for at least 6months and to estimate the proportion having objective tumor response. Results All 28 enrolled patients were eligible and evaluable. Median age: 62years. Most common histologies: 32% Grade 1/2 endometrioid and 54% serous tumors. Prior treatment: 1 or 2 regimens in 82% and 18% of patients, respectively. Eighteen patients received prior radiation therapy. Patients received 1–12 cycles of dalantercept, and 46% of patients received ≤2cycles. The most common adverse events (AE) were fatigue, anemia, constipation and peripheral edema. Grade 3/4 AEs occurred in 39% and 4% of patients. One grade 5 gastric hemorrhage in a patient with a history of radiation fibrosis/small bowel obstruction was deemed possibly dalantercept-related. All patients are off study: 86% for PD. No ORs were observed; 57% had stable disease and 11% had TPFS>6 mos. Median progression-free and overall survival: 2.1months (90% CI: 1.4–3.2) and 14.5months (90% CI: 7.0–17.5), respectively. Conclusions Dalantercept has insufficient single agent activity in recurrent EMC to warrant further investigation at this dose level and schedule.

Objective Carcinosarcomas of the female genital tract, also called malignant mixed mullerian tumors, are aggressive biphasic tumors. Second-line treatment options in the recurrent/persistent setting have yielded marginal responses. Given the potential role of angiogenesis in the gynecological carcinomas, pazopanib, a VEGFR inhibitor, was investigated in the management of patients with recurrent carcinosarcoma of the uterus. Methods Eligible patients had histologically confirmed carcinosarcoma of the uterus, a maximum of two prior lines of therapy, adequate renal, hepatic and hematologic function and a performance status of 0–2. Pazopanib was administered orally at 800mg. Two dose reductions were allowed. The primary objective was to ascertain the activity of pazopanib as measured by the proportion of patients who survive progression-free for at least six months and the proportion of patients that have objective tumor responses. Secondary objectives included the frequency and severity of adverse events as assessed by CTCAE v4.0. Results Of the 22 enrolled patients, 19 were eligible and evaluable for toxicity and survival. No patients had a partial or complete response (90% confidence interval [CI]: 0%, 14.6%). Three patients (15.8%) had PFS ≥6months (90% CI: 4.4%, 35.9%). The median PFS was 2.0months (first and third quartiles were 1.6 and 4.0months, respectively). The median overall survival was 8.7months (first and third quartiles were 2.6 and 14.0months, respectively). Conclusion Pazopanib demonstrated minimal activity as a second or third line treatment for advanced uterine carcinosarcoma. Potential clinical trial participation should be discussed with the patients.

BACKGROUND: The 5-year survival rate of patients with recurrent epithelial ovarian cancer is only 30%, in part due to relapse and resistance to first-line platinum-based chemotherapy. Even with marked progress toward understanding ovarian cancer biology, the translation of research findings into new therapies is still an enormous barrier to progress. Recent data suggests a 90% failure rate for new oncology drugs in the clinic. Development and preclinical testing of new cancer therapies has been limited by the availability of clinically relevant models that recapitulate the molecular and phenotypic characteristics of primary ovarian cancers. To overcome this barrier, we have initiated collaborative project between Stephenson Cancer Center (SCC) and Oklahoma Medical Research Foundation (OMRF) with the goal to generate a biobank of patient-derived xenograft (PDX) models derived directly from ovarian cancer patients undergoing therapy. RESULTS: PDX tumor models are generated in the Patient-Derived Xenograft and Preclinical Therapeutics (PDX-PCT) Core at OMRF and used to improve preclinical evaluation of new drugs towards more personalized medicine. We have collected blood samples and tumor tissues from consenting patients having primary debulking surgery at Stephenson Cancer Center since 2015 (>140 unique patients). Fresh tumor tissue is minced into small tumor chunks (~2 mm) and implanted into immunocompromised mice. PDXs are expanded for 3-4 passages and characterized based on tumor type, histology and molecular characteristics. Immunohistochemical and molecular analysis showed that histology of the original patient tumors as well as the expression of commonly used markers for high-grade serous ovarian cancer such as cytokeratin, PAX8 and WT1 are perfectly maintained in the derivative PDX lines. Genotyping of patients' tumors and their corresponding PDXs using Illumina's Exome Array revealed that single nucleotide polymorphism (SNP) profile found in the original tumors is perfectly maintained in PDX lines. One of the PDX limitations is that human tumor stromal and immune cells are being replaced with mouse equivalents upon in vivo propagation of PDXs, which negatively affects quality of genomic or proteomic analyses. To overcome this challenge, we optimized a method to deplete mouse cells from PDX tumors by magnetic cells separation. Our data showed that ovarian cancer PDXs contain around 28-54% of human tumor cells, where the rest are mouse cells. We also optimized protocols to utilize pure population of human tumor cells isolated from PDXs to transduce these with lentiviral vectors expressing GFP and/or luciferase to generate luciferized PDXs. Luciferized ovarian PDXs are excellent models used for non-invasive orthotopic tumor growth and drug response monitoring. CONCLUSIONS: Collection of our PDXs illustrates heterogeneity and diversity of human ovarian tumors. However, each PDX maintains essential molecular features of the original patients' tumor. Our goal is to generate clinically faithful ovarian tumor models that will provide a platform to learn more about cancer biology and to screen these for new better therapies. Citation Format: Magdalena Cybula, Katherine Moxley, Lin Wang, Luyao Wang, Magdalena Bieniasz. UTILIZATION OF PATIENT-DERIVED TUMOR XENOGRAFT (PDX) MODELS IN ONCOLOGY [abstract]. In: Proceedings of the 12th Biennial Ovarian Cancer Research Symposium; Sep 13-15, 2018; Seattle, WA. Philadelphia (PA): AACR; Clin Cancer Res 2019;25(22 Suppl):Abstract nr GMM-021.

Objectives Controversy continues over the importance of lymph node (LN) status in treating and predicting recurrence in endometrial cancer. Several predictive models are available which use uterine factors to stratify risk groups. Our objective was to determine how LN status affects recurrence and survival compared to uterine factors alone. Methods A retrospective review was performed of patients undergoing complete surgical staging for clinical stage 1 endometrioid adenocarcinoma of the uterus. Patients were assessed based on PORTEC 1 high intermediate risk (H-IR) criteria (2 factors : age>60, grade 3, >50% DOI), GOG-99 H-IR criteria (age >70+1 factor, age 50–70+2 factors, any age +3 factors: grade 2 or 3, LVSI, >50% DOI), and PORTEC 2 criteria. Rates of nodal involvement, recurrence rates, PFS, and OS were compared. Results We identified 352 clinical stage I patients with positive LN in 24% (87). 175 patients met PORTEC 1 eligibility and 66 met H-IR criteria. Rates of LN positivity were similar among groups (18.4% vs 19.7%, p =0.83) but recurrence rates were dissimilar (7.4% vs 27.3%, p =0.0004). Only 93 met PORTEC 2 criteria for treatment with no association between LN status, recurrence, and eligibility. 188 patients met H-IR eligibility criteria for GOG-99 with LN positive and recurrence rates higher in the H-IR group compared to GOG-99 eligible (34.6% vs 16.3%, p =0.0004, 28.3% vs. 10.6%, p =0.0002). Conclusions Patients with H-IR disease based on uterine characteristics alone have substantial risk of nodal involvement. Knowledge of LN status may better define risk, prognosis, and postoperative treatment.

The article examines current treatment options in patients with endometrial carcinoma, the role of drug resistance, and the rationale for the use of epothilones in treating this disease., Adenocarcinoma of the endometrium represents the most common gynecologic malignancy in developed countries. Although early-stage cancers are effectively treated surgically, commonly without adjuvant therapy, the treatment of high-risk and advanced disease is more complex. Chemotherapy has evolved into an important modality in high-risk early-stage and advanced-stage disease, and in recurrent endometrial cancer. Taxane-based therapy consistently demonstrates the highest response rates in the first-line and salvage settings of endometrial cancer. Unfortunately, response to chemotherapy is modest and strategies are needed to predict chemotherapy-responsive and chemotherapy-resistant populations. Chemotherapy resistance mediated by overexpression of drug efflux pump proteins and mutations in β-tubulin isoforms in both primary and recurrent disease represent unique treatment challenges and highlight the need for new agents that are less susceptible to these known resistance pathways. Epothilone B analogs are novel cytotoxic agents with activity in solid tumors, including advanced/recurrent endometrial carcinoma, and may have unique properties that can overcome resistance in some settings. These agents alone and in combination represent a new therapeutic opportunity in endometrial carcinoma.

5589Background: Protocol GOG-258 randomized Cis-RT+CP or CP for 6 cycles to patients (pts) with stage III/IVA endometrial carcinoma (Matei et al, ASCO 2017). Recurrence-free survival was the primar...

5505Background: We conducted a phase III trial to determine whether adjuvant chemotherapy with gemcitabine-docetaxel followed by doxorubicin improves survival compared to observation in women with ...

Primary carcinoma of the fallopian tube (PCFT) accounts for perhaps 1% of genital tract cancers. The investigators undertook a matched, case-control comparison of 96 women with a diagnosis of PCFT and 189 control women having ovarian carcinoma (OC). The groups were matched for age, tumor stage, and the presence of residual disease. All patients were surgically staged and, if indicated, given platinum-based chemotherapy. Fifty early-stage (FIGO stage I or II) cases of PCFT were matched with 97 OC patients. A regimen of carboplatinum and paclitaxel was used in more than 80% of cases. Median follow-up intervals for the PCFT and OC groups were 57 and 42 months, respectively. The respective 5-year overall survival rates were 95% and 76%. Excluding cases of stage IA PCFT, the 5-year survival rate was 92% for patients with PCFT and 70% for those with OC. Progression-free 5-year survival rates were 62% and 50%, respectively, not a significant difference. Excluding early-stage PCFT cases that were found incidentally during surgery for benign conditions or at the time of salpingo-oophorectomy, 5-year survival was 97% for PCFT cases and 77% for cases of OC. When 46 cases of stage III/IV PCFT were matched with 92 OC cases and followed up for nearly 3 years, the 3-year overall survival rate was 59% for both groups. Progression-free 3-year survival rates were 26% for PCFT patients and 21% for control patients with OC (P = 0.46). These findings should lead clinicians to be assured that treatment of PCFT should mirror that of OC.

5594 Background: Angiogenesis has a role in endometrial cancer (EC) progression and prognosis. Single agent bevacizumab had a response rate (RR) of 13% and 6 month progression-free survival of 40% ...

Background: TP53 is commonly mutated in ovarian cancer. As potential agents targeting TP53 mutant or wt are under development, the efficiency and accuracy for determination of TP53 mutations in a clinical trial was evaluated. Methods: Eligible patients, including relapsed, platinum-sensitive ovarian, fallopian tube, or primary peritoneal cancer, underwent pre-screening for a clinical trial with MK1775, eligibility for which was determined by the presence of functional TP53 mutations (Brana I et al, ASCO 2013). Single base substitution and single base deletion mutations in exons 2 - 11 and the flanking splice junction in the TP53 gene were analyzed using AmpliChip p53 Assay (Roche Molecular Diagnostics, California) on archival tumor specimens. Results: Seventy-five women were screened for eligibility based on TP53; 43 had TP53 mutations, 27 were TP53 wild-type (wt), and 5 undetermined (Table 1). No clustering of mutations to define hot spots was evident. The most commonly mutated region was exon 5 (11 mutations). Missense mutations were the most common mutation type (69.7%); although, nonsense (14 %), splice (14 %), and frame shift mutations (2.3%) were also observed (Table 1). Most of the missense mutations were in exons 5 to 8 (90%). The mean turnaround time from sample reception to final TP53 status report was 3 days (range 1:14). Conclusions: The TP53 mutational status has been successfully determined in 93.3% of patients with a short turnaround time, supporting the feasibility of TP53 determination in the clinical setting. In our patient population, 57.3% had a TP53 mutation. Potential geographic differences in the incidence TP53 mutations cannot be evaluated due to the limited sample size; this hypothesis should be further evaluated in a larger patient population Citation Information: Mol Cancer Ther 2013;12(11 Suppl):B181. Citation Format: Irene Brana, Kathleen Moore, Stephen Welch, Ronnie Shapira-Frommer, Darlene Gibbon, Hal Hirte, Saul Rivkin, Robert Coleman, Gerry Prendergast, Katherine M. Moxley, Ying-Ming Jou, Michelle Marinucci, Tomoko Freshwater, Sharon McCarthy, Mark Lee Anthony, Shelonitda Rose, Amit M. Oza. TP53 mutation screening in patients with recurrent platinum-sensitive ovarian cancer. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2013 Oct 19-23; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2013;12(11 Suppl):Abstract nr B181.

Objective Cervical intraepithelial neoplasia grade 3 (CIN3), the immediate cervical cancer precursor, is a target of cervical cancer prevention. However, less than half of CIN3s will progress to cancer. Routine treatment of all CIN3s and the majority of CIN2s may lead to overtreatment of many lesions that would not progress. To improve our understanding of CIN3 natural history, we performed a detailed characterization of CIN3 heterogeneity in a large referral population in the US. Methods We examined 309 CIN3 cases in the SUCCEED, a large population-based study of women with abnormal cervical cancer screening results. Histology information for 12 individual loop electrosurgical excision procedure (LEEP) segments was evaluated for each woman. We performed case-case comparisons of CIN3s to analyze determinants of heterogeneity and screening test performance. Results CIN3 cases varied substantially by size (1–10 LEEP segments) and by presentation with concomitant CIN2 and CIN1. All grades of CINs were equally distributed over the cervical surface. In half of the women, CIN3 lesions were found as multiple distinct lesions on the cervix. Women with large and solitary CIN3 lesions were more likely to be older, have longer sexual activity span, and have fewer multiple high risk HPV infections. Screening frequency, but not HPV16 positivity, was an important predictor of CIN3 size. Large CIN3 lesions were also characterized by high-grade clinical test results. Conclusions We demonstrate substantial heterogeneity in clinical and pathological presentation of CIN3 in a US population. Time since sexual debut and participation in screening were predictors of CIN3 size. We did not observe a preferential site of CIN3 on the cervical surface that could serve as a target for cervical biopsy. Cervical cancer screening procedures were more likely to detect larger CIN3s, suggesting that CIN3s detected by multiple independent diagnostic tests may represent cases with increased risk of invasion.

Erratum to “Induction of death receptor ligand-mediated apoptosis in epithelial ovarian carcinoma: The search for sensitizing agents” [Gynecol. Oncol. 115 (2009) 438–442] Katherine Marie Moxley , Shylet Chengedza , Doris Mangiaracina Benbrook a,b,⁎ a Department of Obstetrics and Gynecology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA b Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA