Pembrolizumab plus Chemotherapy in Advanced Endometrial Cancer.

BACKGROUND: Standard first-line chemotherapy for endometrial cancer is paclitaxel plus carboplatin. The benefit of adding pembrolizumab to chemotherapy remains unclear. METHODS: In this double-blind, placebo-controlled, randomized, phase 3 trial, we assigned 816 patients with measurable disease (stage III or IVA) or stage IVB or recurrent endometrial cancer in a 1:1 ratio to receive pembrolizumab or placebo along with combination therapy with paclitaxel plus carboplatin. The administration of pembrolizumab or placebo was planned in 6 cycles every 3 weeks, followed by up to 14 maintenance cycles every 6 weeks. The patients were stratified into two cohorts according to whether they had mismatch repair-deficient (dMMR) or mismatch repair-proficient (pMMR) disease. Previous adjuvant chemotherapy was permitted if the treatment-free interval was at least 12 months. The primary outcome was progression-free survival in the two cohorts. Interim analyses were scheduled to be triggered after the occurrence of at least 84 events of death or progression in the dMMR cohort and at least 196 events in the pMMR cohort. RESULTS: In the 12-month analysis, Kaplan-Meier estimates of progression-free survival in the dMMR cohort were 74% in the pembrolizumab group and 38% in the placebo group (hazard ratio for progression or death, 0.30; 95% confidence interval [CI], 0.19 to 0.48; P<0.001), a 70% difference in relative risk. In the pMMR cohort, median progression-free survival was 13.1 months with pembrolizumab and 8.7 months with placebo (hazard ratio, 0.54; 95% CI, 0.41 to 0.71; P<0.001). Adverse events were as expected for pembrolizumab and combination chemotherapy. CONCLUSIONS: In patients with advanced or recurrent endometrial cancer, the addition of pembrolizumab to standard chemotherapy resulted in significantly longer progression-free survival than with chemotherapy alone. (Funded by the National Cancer Institute and others; NRG-GY018 ClinicalTrials.gov number, NCT03914612.).

Dostarlimab for Primary Advanced or Recurrent Endometrial Cancer.

BACKGROUND: Dostarlimab is an immune-checkpoint inhibitor that targets the programmed cell death 1 receptor. The combination of chemotherapy and immunotherapy may have synergistic effects in the treatment of endometrial cancer. METHODS: We conducted a phase 3, global, double-blind, randomized, placebo-controlled trial. Eligible patients with primary advanced stage III or IV or first recurrent endometrial cancer were randomly assigned in a 1:1 ratio to receive either dostarlimab (500 mg) or placebo, plus carboplatin (area under the concentration-time curve, 5 mg per milliliter per minute) and paclitaxel (175 mg per square meter of body-surface area), every 3 weeks (six cycles), followed by dostarlimab (1000 mg) or placebo every 6 weeks for up to 3 years. The primary end points were progression-free survival as assessed by the investigator according to Response Evaluation Criteria in Solid Tumors (RECIST), version 1.1, and overall survival. Safety was also assessed. RESULTS: Of the 494 patients who underwent randomization, 118 (23.9%) had mismatch repair-deficient (dMMR), microsatellite instability-high (MSI-H) tumors. In the dMMR-MSI-H population, estimated progression-free survival at 24 months was 61.4% (95% confidence interval [CI], 46.3 to 73.4) in the dostarlimab group and 15.7% (95% CI, 7.2 to 27.0) in the placebo group (hazard ratio for progression or death, 0.28; 95% CI, 0.16 to 0.50; P<0.001). In the overall population, progression-free survival at 24 months was 36.1% (95% CI, 29.3 to 42.9) in the dostarlimab group and 18.1% (95% CI, 13.0 to 23.9) in the placebo group (hazard ratio, 0.64; 95% CI, 0.51 to 0.80; P<0.001). Overall survival at 24 months was 71.3% (95% CI, 64.5 to 77.1) with dostarlimab and 56.0% (95% CI, 48.9 to 62.5) with placebo (hazard ratio for death, 0.64; 95% CI, 0.46 to 0.87). The most common adverse events that occurred or worsened during treatment were nausea (53.9% of the patients in the dostarlimab group and 45.9% of those in the placebo group), alopecia (53.5% and 50.0%), and fatigue (51.9% and 54.5%). Severe and serious adverse events were more frequent in the dostarlimab group than in the placebo group. CONCLUSIONS: Dostarlimab plus carboplatin-paclitaxel significantly increased progression-free survival among patients with primary advanced or recurrent endometrial cancer, with a substantial benefit in the dMMR-MSI-H population. (Funded by GSK; RUBY ClinicalTrials.gov number, NCT03981796.).

Clinical research in endometrial cancer: consensus recommendations from the Gynecologic Cancer InterGroup.

The Gynecologic Cancer InterGroup (GCIG) Endometrial Cancer Consensus Conference on Clinical Research (ECCC) was held in Incheon, South Korea, Nov 2-3, 2023. The aims were to develop consensus statements for future trials in endometrial cancer to achieve harmonisation on design elements, select important questions, and identify unmet needs. All 33 GCIG member groups participated in the development, refinement, and finalisation of 18 statements within four topic groups, addressing adjuvant treatment in high-risk disease; treatment for metastatic and recurrent disease; trial designs for rare endometrial cancer subgroups and special circumstances; and specific methodology and adaptation for trials in low-resource settings. In addition, eight areas of unmet need were identified. This was the first GCIG Consensus Conference to include patient advocates and an expert on inclusion, diversity, equity, and access to take part in all aspects of the process and output. Four early-career investigators were also selected for participation, ensuring that they represented different GCIG member groups and regions. Unanimous consensus was obtained for 16 of the 18 statements, with 97% concordance for the remaining two. Using the described methodology from previous Ovarian Cancer Consensus Conferences, this conference did not require even one minority statement. The high acceptance rate following active involvement in the preparation, discussion, and refinement of the statements by all representatives confirmed the consensus progress within a global academic setting, and the expectation that the ECCC will lead to greater harmonisation, actualisation, inclusion, and resolution of unmet needs in clinical research for individuals living with and beyond endometrial cancer worldwide.

Primary results and characterization of patients with exceptional outcomes in a phase 1b study combining PARP and MEK inhibition, with or without anti-PD-L1, for BRCA wild-type, platinum-sensitive, recurrent ovarian cancer.

BACKGROUND: This phase 1b study (ClinicalTrials.gov identifier NCT03695380) evaluated regimens combining PARP and MEK inhibition, with or without PD-L1 inhibition, for BRCA wild-type, platinum-sensitive, recurrent ovarian cancer (PSROC). METHODS: Patients with PSROC who had received one or two prior treatment lines were treated with 28-day cycles of cobimetinib 60 mg daily (days 1-21) plus niraparib 200 mg daily (days 1-28) with or without atezolizumab 840 mg (days 1 and 15). Stage 1 assessed safety before expansion to stage 2, which randomized patients who had BRCA wild-type PSROC to receive either doublet or triplet therapy, stratified by genome-wide loss of heterozygosity status (<16% vs. ≥16%; FoundationOne CDx assay) and platinum-free interval (≥6 to <12 vs. ≥12 months). Coprimary end points were safety and the investigator-determined objective response rate (ORR) according to Response Evaluation Criteria in Solid Tumors (RECIST). Potential associations between genetic parameters and efficacy were explored, and biomarker profiles of super-responders (complete response or those with progression-free survival [PFS] >15 months) and progressors (disease progression as the best response) were characterized. RESULTS: The ORR in patients who had BRCA wild-type PSROC was 35% (95% confidence interval, 20%-53%) with the doublet regimen (n = 37) and 27% (95% confidence interval, 14%-44%) with the triplet regimen (n = 37), and the median PFS was 6.0 and 7.4 months, respectively. Post-hoc analyses indicated more favorable ORR and PFS in the homologous recombination-deficiency-signature (HRDsig)-positive subgroup than in the HRDsig-negative subgroup. Tolerability was consistent with the known profiles of individual agents. NF1 and MKNK1 mutations were associated with sustained benefit from the doublet and triplet regimens, respectively. CONCLUSIONS: Chemotherapy-free doublet and triplet therapy demonstrated encouraging activity, including among patients who had BRCA wild-type, HRDsig-positive or HRDsig-negative PSROC harboring NF1 or MKNK1 mutations.

A toolkit for a modern gynecologic oncology tissue bank.

OBJECTIVES: Tissue banking procedures have evolved to keep pace with precision medicine, technology, emerging understanding of racial disparities, and regulatory requirements. However, there is little published guidance regarding strategies to create and maintain a successful biorepository. Our objective is to describe the infrastructure and protocols used by our Gynecologic Oncology Tissue Bank. METHODS: Our Tissue Bank was founded in 1992. In August 2022, internal funding was used to modernize the Tissue Bank. We hired three full-time employees, implemented universal screening of patients treated by gynecologic oncology faculty, updated consenting protocols, and standardized communication with providers. Tumor tissue, blood derivatives, ascites, and pleural fluid were collected from eligible, consenting patients and processed. Patient-derived cell lines and organoids were generated. For quality control purposes, one formalin-fixed, paraffin-embedded (FFPE) sample per tissue site was analyzed by a board-certified pathologist. All samples were labeled and tracked in an OpenSpecimen collection protocol and clinically annotated in a secure database. RESULTS: From August 2022 to October 2023, 227 patients (83% white, 15% Black, 1% Asian) were enrolled and 4249 specimens were collected. Adherent cell lines were generated from 15 patients with ovarian cancer and cell suspensions for organoid generation were collected from 46 patients with ovarian cancer. A recharge center was established to self-sustain the Tissue Bank. Samples have been shared with academic and commercial collaborators. CONCLUSIONS: Our Tissue Bank has enrolled a large number of diverse patients, collected numerous specimen types, and collaborated widely. The procedures described here provide guidance for other institutions establishing similar resources.

Results of a randomized phase II trial of paclitaxel and carboplatin versus bleomycin, etoposide and cisplatin for newly diagnosed and recurrent Chemonaive stromal ovarian tumors: An NRG oncology/gynecologic oncology group study14.

OBJECTIVES: To assess the efficacy and toxicity of paclitaxel and carboplatin (PC) compared to bleomycin, etoposide, and cisplatin (BEP) for treatment of newly diagnosed Stage IIA-IV or recurrent chemotherapy-naive ovarian sex cord-stromal tumors (SCST). METHODS: This phase II noninferiority trial randomly assigned patients to receive PC (6 cycles P 175 mg/m2 and C AUC = 6 IV every 3 weeks), or BEP (4 cycles B 20 units/m2 IV push day 1, E 75 mg/m2 IV days 1-5, and cisplatin 20 mg/m2 IV days 1-5 every 3 weeks). The primary endpoint was progression- free survival (PFS). This trial is registered with ClinicalTrials.gov, NCT01042522. RESULTS: At the interim analysis, 63 patients (31 PC and 32 B.P. had accrued between Feb 8, 2010 and Apr 30, 2020. Median age was 48 years. 87% had granulosa cell tumors. 37% had measurable disease. The DSMB closed accrual early for futility of PC arm. The futility analysis was supported by an estimated HR = 1.11 [95% CI: 0.57 to 2.13] which exceeded the pre-determined threshold for non-inferiority (1.10). Median PFS was 27.7 months [11.2 to 41.0] for PC and 19.7 months for BEP [95% CI: 10.4-52.7]. PC patients had fewer grade 3 or higher adverse events (PC 77% vs BEP 90%). CONCLUSIONS: The study met its pre-specified criterion for stopping early for futility and so failed to demonstrate non-inferiority of PC versus BEP in ovarian SCSTs, in a non-inferiority test with a hazard ratio margin of 1.1. Both PC and BEP may be considered in patients with advanced/recurrent SCST.

Racial, ethnic and country of origin disparities in aggressive endometrial cancer histologic subtypes.

OBJECTIVE: This study investigated the risk of an aggressive endometrial cancer (EC) diagnosis by race, ethnicity, and country of origin to further elucidate histologic disparities in non-Hispanic Black (NHB), Hispanic, Asian/Pacific Islander (API), American Indian/Alaskan Native (AIAN) vs. non-Hispanic White (NHW) patients, particularly in Hispanic or API subgroups. METHODS: Patient diagnosed between 2004 and 2020 with low grade (LG)-endometrioid endometrial cancer (ECC) or an aggressive EC including grade 3 EEC, serous carcinoma, clear cell carcinoma, mixed epithelial carcinoma, or carcinosarcoma in the National Cancer Database were studied. The odds ratio (OR) and 95% confidence interval (CI) for diagnosis of an aggressive EC histology was estimated using logistic modeling. RESULTS: There were 343,868 NHW, 48,897 NHB, 30,013 Hispanic, 15,015 API and 1646 AIAN patients. The OR (95% CI) for an aggressive EC diagnosis was 3.07 (3.01-3.13) for NHB, 1.08 (1.06-1.11) for Hispanic, 1.17 (1.13-1.21) for API and 1.07 (0.96-1.19) for AIAN, relative to NHW patients. Subset analyses by country of origin illustrated the diversity in the OR for an aggressive EC diagnosis among Hispanic (1.18 for Mexican to 1.87 for Dominican), Asian (1.14 Asian Indian-Pakistani to 1.48 Korean) and Pacific Islander (1.00 for Hawaiian to 1.33 for Samoan) descendants. Hispanic, API and AIAN patients were diagnosed 5-years younger that NHW patients, and the risk for an aggressive EC histology were all significantly higher than NHW patients after correcting for age. Insurance status was another independent risk factor for aggressive histology. CONCLUSIONS: Risk of an aggressive EC diagnosis varied by race, ethnicity, and country of origin. NHB patients had the highest risk, followed by Dominican, South/Central American, Cuban, Korean, Thai, Vietnamese, and Filipino descendants.

Disease progression, survival, and molecular disparities in Black and White patients with endometrioid endometrial carcinoma in real-world registries and GOG/NRG oncology randomized phase III clinical trials.

OBJECTIVE: Investigate racial disparities in outcomes and molecular features in Black and White patients with endometrioid endometrial carcinoma (EEC). METHODS: Black and White patients diagnosed with EEC who underwent hysterectomy ± adjuvant treatment in SEER, National Cancer Database (NCDB), the Genomics Evidence Neoplasia Information Exchange (GENIE) project (v.13.0), and eight NCI-sponsored randomized phase III clinical trials (RCTs) were studied. Hazard ratio (HR) and 95% confidence interval (CI) were estimated for cancer-related death (CRD), non-cancer death (NCD), and all-cause death. RESULTS: Black (n = 4397) vs. White (n = 47,959) patients in SEER had a HR (95% CI) of 2.04 (1.87-2.23) for CRD and 1.22 (1.09-1.36) for NCD. In NCDB, the HR (95% CI) for death in Black (n = 13,468) vs. White (n = 155,706) patients was 1.52 (1.46-1.58) dropping to 1.29 (1.23-1.36) after propensity-score matching for age, comorbidity, income, insurance, grade, stage, LVSI, and treatment. In GENIE, Black (n = 109) vs. White (n = 1780) patients had fewer PTEN, PIK3R1, FBXW7, NF1, mTOR, CCND1, and PI3K-pathway-related gene mutations. In contrast, TP53 and DNA-repair-related gene mutation frequency as well as tumor mutational burden-high status were similar in Black and White patients. In RCTs, Black (n = 187) vs. White (n = 2877) patients were more likely to have advanced or recurrent disease, higher grade, worse performance status and progressive disease. Risk of death in Black vs. White patients in RCTs was 2.19 (1.77-2.71) persisting to 1.32 (1.09-1.61) after matching for grade, stage, and treatment arm while balancing age and performance status. CONCLUSIONS: Differences exist in clinical presentation, outcomes, and molecular features in Black vs. White patients with EEC in real-world registries and RCTs. Targeted-drug development, strategies to modify social determinants, and diverse inclusion in RCTs are approaches to reduce disparities.

Accuracy of surveillance serum squamous cell carcinoma antigen for cervical cancer recurrence after definitive chemoradiation.

OBJECTIVE: Recurrence remains a significant clinical problem for patients with cervical cancer, and early detection may improve outcomes. Serum squamous cell carcinoma antigen (SCCA) is a biomarker of prognosis and response to chemoradiotherapy. We hypothesized that elevated serum SCCA during surveillance is sensitive and specific for recurrence. METHODS: Pre-treatment and follow-up serum SCCA from patients treated with definitive-intent radiotherapy were measured via enzyme-linked immunosorbent assay in a Clinical Laboratory Improvement Amendments (CLIA)-certified laboratory and analyzed retrospectively. Follow-up SCCA was defined as the value closest to recurrence, or as last available for patients without recurrence. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of follow-up SCCA for recurrence was determined for the whole cohort (Cohort 1), for patients with elevated (Cohort 2), and normal pre-treatment SCCA (Cohort 3). Patterns of failure were also evaluated. RESULTS: Of 227 patients in Cohort 1, 23% experienced recurrence, and 17% died of cervical cancer. Mean follow-up SCCA was 0.9 (±2.5) for patients with no recurrence and 6.0 (±18.7) for patients with recurrence (p=0.02). Sensitivity, specificity, PPV, and NPV of follow-up SCCA for recurrence in Cohort 1 were 38.5%, 97.1%, 80%, and 84.2%, and for patients in Cohort 2 were 54.5%, 95%, 78.3%, and 86.5%, respectively. Four of 86 patients in Cohort 3 had an elevated follow-up SCCA, two of these at the time of recurrence. Elevated pre-treatment SCCA and follow-up SCCA were associated with isolated pelvic recurrence. CONCLUSIONS: Surveillance serum SCCA has high specificity and NPV for recurrence, and may be of limited utility in patients with normal pre-treatment SCCA.

Patient-reported outcomes in the subpopulation of patients with mismatch repair-deficient/microsatellite instability-high primary advanced or recurrent endometrial cancer treated with dostarlimab plus chemotherapy compared with chemotherapy alone in the ENGOT-EN6-NSGO/GOG3031/RUBY trial.

OBJECTIVE: In the ENGOT-EN6-NSGO/GOG3031/RUBY trial, dostarlimab+carboplatin-paclitaxel demonstrated significant improvement in progression free survival and a positive trend in overall survival compared with placebo+carboplatin-paclitaxel, with manageable toxicity, in patients with primary advanced or recurrent endometrial cancer. Here we report on patient-reported outcomes in the mismatch repair-deficient/microsatellite instability-high population, a secondary endpoint in the trial. METHODS: Patients were randomized 1:1 to dostarlimab+carboplatin-paclitaxel or placebo+carboplatin-paclitaxel every 3 weeks for 6 cycles followed by dostarlimab or placebo monotherapy every 6 weeks for ≤3 years or until disease progression. Patient-reported outcomes, assessed with the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 and Endometrial Cancer Module, were prespecified secondary endpoints. A mixed model for repeated measures analysis, a prespecified exploratory analysis, was conducted to generate least-squares means to compare between-treatment differences while adjusting for correlations across multiple time points within a patient and controlling for the baseline value. Results are provided with 2-sided, nominal p values. RESULTS: Of 494 patients enrolled, 118 were mismatch repair-deficient/microsatellite instability-high. In this population, mean change from baseline to end of treatment showed visual improvements in global quality of life (QoL), emotional and social function, pain, and back/pelvis pain for dostarlimab+carboplatin-paclitaxel. Meaningful differences (least-squares mean [standard error]) favoring the dostarlimab arm were reported for change from baseline to end of treatment for QoL (14.7 [5.45]; p=0.01), role function (12.7 [5.92]); p=0.03), emotional function (14.3 [4.92]; p<0.01), social function (13.5 [5.43]; p=0.01), and fatigue (-13.3 [5.84]; p=0.03). CONCLUSIONS: Patients with mismatch repair-deficient/microsatellite instability-high primary advanced or recurrent endometrial cancer receiving dostarlimab+carboplatin-paclitaxel demonstrated improvements in several QoL domains over patients receiving placebo+carboplatin-paclitaxel. The observed improvements in progression free survival and overall survival while improving or maintaining QoL further supports dostarlimab+carboplatin-paclitaxel as a standard of care in this setting. TRIAL REGISTRATION: ClinicalTrials.gov NCT03981796.

Differential outcomes and immune checkpoint inhibitor response among endometrial cancer patients with MLH1 hypermethylation versus MLH1 "Lynch-like" mismatch repair gene mutation.

OBJECTIVES: To identify differential survival outcomes and immune checkpoint inhibitor (ICI) response in MLH1 hypermethylated versus MLH1 mutated ("Lynch-like") endometrial tumors and determine whether their molecular profiles can elucidate the differential outcomes. METHODS: 1673 mismatch repair deficient endometrial tumors were analyzed by next-generation sequencing and whole transcriptome sequencing (Caris Life Sciences, Phoenix, AZ). PD-L1, ER, and PR were tested by immunohistochemistry and immune cell infiltrates were calculated using MCP-counter. Significance was determined using Chi-square and Mann-Whitney U tests and adjusted for multiple comparisons. Overall survival (OS) was depicted using Kaplan-Meier survival curves. RESULTS: The endometrial cancer cohort comprised 89.2% patients with MLH1 hypermethylated tumors and 10.8% with MLH1 mutated tumors, with median ages of 67 and 60 years, respectively (p < 0.01). Patients with MLH1 hypermethylated tumors had significantly worse OS and trended toward worse OS following ICI treatment than patients with MLH1 mutated tumors. The immune microenvironment of MLH1 hypermethylated relative to MLH1 mutated was characterized by decreased PD-L1 positivity, immune checkpoint gene expression, immune cell infiltration, T cell inflamed scores, and interferon gamma (IFNγ) scores. MLH1 hypermethylation was also associated with decreased mutation rates in TP53 and DNA damage repair genes, but increased rates of JAK1, FGFR2, CCND1, and PTEN mutations, as well as increased ER and PR positivity. CONCLUSIONS: Endometrial cancer patients with MLH1 hypermethylation display significantly decreased survival and discrepant immunotherapy responses compared to patients with MLH1 mutated tumors, which was associated with differential mutational profiles, a more immune cold phenotype, and increased ER/PR expression in MLH1 hypermethylated tumors. Providers may consider early transition from single agent ICI to a multi-agent regimen or hormonal therapy for patients with MLH1 hypermethylated tumors.

HER2+ endometrioid endometrial cancer possesses distinct molecular and immunologic features associated with a more active immune microenvironment and worse prognosis.

OBJECTIVE: HER2 status is not routinely evaluated in endometrioid endometrial cancer (E-EMCA), though it is frequently overexpressed or amplified in high grade E-EMCA and uterine serous carcinoma. Defining characteristics and survival outcomes of HER2+ E-EMCA could reveal subsets of patients who may benefit from targeted therapies. METHODS: 2927 E-EMCA tumors from the Caris Life Sciences database were analyzed by next-generation sequencing and whole exome sequencing, whole transcriptome sequencing, and immunohistochemistry for molecular and genomic features in a CLIA/CAP-certified laboratory (Caris Life Sciences, Phoenix, AZ). HER2 status was determined by transcriptomic cutoff extrapolated from uterine serous carcinoma. The relationship between HER2 status and patient outcomes was determined by Kaplan-Meier analysis. RESULTS: HER2 positivity was detected in 5.47% of E-EMCA. Differences in molecular alterations based on HER2 status were most apparent in microsatellite stable (MSS) tumors, which displayed increased TP53 mutations and loss of heterozygosity (LOH) and decreased PTEN and CTNNB1 mutations. HER2+ tumors had increased immune checkpoint gene expression and immune cell infiltration, particularly among MSS tumors. All HER2+ tumors displayed increased MAPK pathway activation scores (MPAS) and patients with HER2+ tumors experienced worse overall survival. CONCLUSIONS: HER2 positivity in E-EMCA corresponds with a unique molecular landscape, particularly in MSS tumors. HER2+ tumors are also associated with increased MAPK pathway activation and exhibit features of a more active immune microenvironment. These findings suggest a potential benefit of HER2 and MAPK targeted therapies as well as immunotherapies in this patient population.

Mixed clear cell/endometrioid and clear cell/serous carcinoma of the uterus are clinicopathologically similar to pure clear cell carcinoma: An NRG Oncology/Gynecologic Oncology Group (GOG-210) study of 311 women.

OBJECTIVES: Clear cell carcinoma is a high-risk subtype of endometrial cancer. Some patients have a mixture of clear cell carcinoma with other histologic types (endometrioid or serous) or cannot be neatly assigned to one of these types. Protocol GOG-8032 within GOG-210 was designed to determine whether these tumors differ from pure clear cell carcinoma in stage at diagnosis, initial pattern of spread, or patient survival. METHODS: The term "mixed" was applied to tumors with multiple identifiable components, and "indeterminate" was applied to tumors with features intermediate between different histologic types. Three hundred eleven women with pure, mixed, or indeterminate clear cell carcinoma were identified in a larger cohort of patients undergoing hysterectomy for endometrial cancer in GOG-210. Histologic slides were centrally reviewed by expert pathologists. Baseline and follow-up data were analyzed. RESULTS: One hundred thirty-six patients had pure clear cell carcinoma and 175 had a mixed or indeterminate clear cell pattern. Baseline clinicopathologic characteristics were similar except for a small difference in age at presentation. Univariate survival analysis confirmed the significance of typical endometrial cancer prognostic factors. Patients in the mixed categories had disease-free and overall survival similar to pure clear cell carcinoma, but the indeterminate clear cell/endometrioid group had longer survival. CONCLUSION: In clear cell endometrial cancer, the presence of a definite admixed endometrioid or serous component did not correlate with a significant difference in prognosis. Patients whose tumors had indeterminate clear cell features had better prognosis. Some of these tumors may be endometrioid tumors mimicking clear cell carcinoma.

Adjuvant Chemotherapy plus Radiation for Locally Advanced Endometrial Cancer.

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.).

The targeted SMAC mimetic SW IV-134 augments platinum-based chemotherapy in pre-clinical models of ovarian cancer.

BACKGROUND: Ovarian cancer is initially responsive to frontline chemotherapy. Unfortunately, it often recurs and becomes resistant to available therapies and the survival rate for advanced and recurrent ovarian cancer is unacceptably low. We thus hypothesized that it would be possible to achieve more durable treatment responses by combining cisplatin chemotherapy with SW IV-134, a cancer-targeted peptide mimetic and inducer of cell death. SW IV-134 is a recently developed small molecule conjugate linking a sigma-2 ligand with a peptide analog (mimetic) of the intrinsic death pathway activator SMAC (second-mitochondria activator of caspases). The sigma-2 receptor is overexpressed in ovarian cancer and the sigma-2 ligand portion of the conjugate facilitates cancer selectivity. The effector portion of the conjugate is expected to synergize with cisplatin chemotherapy and the cancer selectivity is expected to reduce putative off-target toxicities. METHODS: Ovarian cancer cell lines were treated with cisplatin alone, SW IV-134 alone and a combination of the two drugs. Treatment efficacy was determined using luminescent cell viability assays. Caspase-3/7, - 8 and - 9 activities were measured as complementary indicators of death pathway activation. Syngeneic mouse models and patient-derived xenograft (PDX) models of human ovarian cancer were studied for response to SW IV-134 and cisplatin monotherapy as well as combination therapy. Efficacy of the therapy was measured by tumor growth rate and survival as the primary readouts. Potential drug related toxicities were assessed at necropsy. RESULTS: The combination treatment was consistently superior in multiple cell lines when compared to the single agents in vitro. The expected mechanism of tumor cell death, such as caspase activation, was confirmed using luminescent and flow cytometry-based assay systems. Combination therapy proved to be superior in both syngeneic and PDX-based murine models of ovarian cancer. Most notably, combination therapy resulted in a complete resolution of established tumors in all study animals in a patient-derived xenograft model of ovarian cancer. CONCLUSIONS: The addition of SW IV-134 in combination with cisplatin chemotherapy represents a promising treatment option that warrants further pre-clinical development and evaluation as a therapy for women with advanced ovarian cancer.

Management and prognosis of cervical cancer patients treated with definitive radiation therapy who have partial metabolic response on post-therapy positron emission tomography.

OBJECTIVE: To describe the management and outcomes of cervical cancer patients initially treated with radiation who had partial metabolic response (PMR) on three-month post-radiation 18F-fluorodeoxyglucose positron emissions tomography (FDG-PET). METHODS: Cervical cancer patients treated with radiation between 1997 and 2013 who had PMR on initial post-therapy FDG-PET were identified from a prospectively maintained database. Descriptive statistics were used to summarize patient demographics, tumor characteristics, surveillance methods, and treatment modalities. Kaplan-Meier methods were used to estimate progression-free (PFS) and overall survival (OS) for patients who underwent cervical biopsy prior to additional therapies and for patients who were managed with chemotherapy, radiation, surgery or no intervention. RESULTS: PMR was identified in 81/542 (15%) women on initial post-radiation PET. Thirty women underwent cervical biopsy, of whom 14 (47%) had persistent cancer. Nine underwent treatment, (three surgery, five chemotherapy alone and one chemotherapy and radiation) but all died of disease; PFS and OS were similar whether women had surgery, chemoradiation therapy, or no treatment. A second surveillance FDG-PET had PPV and NPV of 91% and 75% for progression, respectively, and identified the 19% percent of patients with persistent disease outside of the cervix. Cervical biopsy had a higher PPV (100%) and lower NPV (62.5%) for progression. At the end of the study period, 46 (57%) patients were dead of disease, including all 8 patients (100%) with para-aortic or supraclavicular involvement. CONCLUSIONS: If PMR is identified on three-month FDG-PET following completion of radiation for cervical cancer, repeat FDG-PET and/or biopsy are indicated to detect persistence and assist in counseling. PMR predicts poor outcomes, particularly for those with positive cervical biopsies and lymphatic involvement.

The impact of tumor size and histology on local control when utilizing high-dose-rate interstitial brachytherapy for gynecologic malignancies.

OBJECTIVE: To report long-term results of an outpatient template-based high-dose-rate interstitial brachytherapy (HDR ISBT) program for the treatment of gynecologic malignancies. METHODS: Patients treated between 2006 and 2020 at an academic hospital with outpatient template based HDR ISBT without spinal or general anesthesia were reviewed. Patients who had previously received HDR ISBT were excluded. Baseline patient, tumor, and treatment characteristics, such as tumor size, histology, and/or total EQD2 including prior external beam radiation therapy (EBRT) were recorded. Local control and overall survival were estimated using the Kaplan-Meier method, and factors associated with local control and overall survival were evaluated using Cox regression analyses. RESULTS: 150 patients received HDR ISBT for a gynecologic tumor and the median follow-up time was 2.98 years (0.89-4.82). Of those, 74/150 (49%) were treated definitively, 69/150 (46%) were treated for tumor recurrence/persistence, and 7/150 (5%) were treated for durable palliation. Median tumor size was 3.00 cm (1.50-4.00). 124/150 (83%) patients received EBRT prior to HDR ISBT. Median HDR ISBT dose was 18 Gy delivered in eight fractions. Local control was 71% (64%-79%), 58% (50%-68%), and 57% (48%-67%) at one, three, and five years, respectively. On multivariate analysis, non-endometrial adenocarcinoma histology (HR = 2.423, 95% CI = 1.011-5.808, p = 0.047) and tumor size ≥ 3 cm (HR = 2.903, 95% CI 1.053-3.441, p = 0.033) were associated with lower local control. CONCLUSIONS: The majority of patients who received outpatient-based twice daily HDR ISBT had long-term local control. Larger tumor size and non-endometrial adenocarcinoma histology were detrimental to local control.

Conditional estimates for uterine serous cancer: Tools for survivorship counseling and planning.

OBJECTIVES: Develop conditional survival and risk-assessment estimates for uterine serous carcinoma (USC) overall and stratified by stage as tools for annual survivorship counseling and care planning. METHODS: Patients in the National Cancer Data Base diagnosed between 2004 and 2014 with stage I-IV USC were eligible. Individuals missing stage or survival data or with multiple malignancies were excluded. Five-year conditional survival was estimated using the stage-stratified Kaplan-Meier method annually during follow-up. A standardized mortality ratio (SMR) estimated the proportion of observed to expected deaths in the U.S. adjusted for year, age, and race. The relationships between prognostic factors and survival were studied using multivariate Cox modeling at diagnosis and conditioned on surviving 5-years. RESULTS: There were 14,575 participants, including 43% with stage I, 8% with stage II, 29% with stage III, and 20% with stage IV USC. Five-year survival at diagnosis vs. after surviving 5-years was 52% vs. 75% overall, 77% vs. 81% for stage I, 57% vs. 72% for stage II, 40% vs. 66% for stage III, and 17% vs. 60% for stage IV USC, respectively (P < 0.0001). Incremental improvements in 5-year conditional survival and reductions in SMR tracked with annual follow-up and higher stage. The adjusted risk of death at diagnosis vs. after surviving 5-years was 1.15 vs. 1.40 per 5-year increase of age, 1.26 vs. 1.68 for Medicaid insurance, 3.92 vs. 2.48 for stage III disease, and 6.65 vs. 2.79 for stage IV disease, respectively (P < 0.0001). CONCLUSION: In USC, the evolution of conditional survival permits annual reassessments of prognosis to tailor survivorship counseling and care planning.

HER2 in Uterine Serous Carcinoma: Testing platforms and implications for targeted therapy.

OBJECTIVE: HER2 is an important prognostic and therapeutic target in uterine serous carcinoma (USC). Optimal HER2 testing platforms have not been defined and guidelines for testing have changed over time. Our objective is to assess the concordance of HER2 positivity based on chromogenic in situ hybridization (CISH), immunohistochemistry (IHC), and next generation sequencing (NGS) and to determine the rate of downstream mutations that may affect response to HER2 directed therapy. METHODS: Utilizing the Caris tumor registry, 2192 USC tumors were identified and analyzed using NGS (NextSeq, 592 Genes and WES, NovaSEQ), IHC, and CISH. PD-L1 expression was tested by IHC. Microsatellite instability was tested by fragment analysis, IHC, and NGS. Tumor mutational burden (TMB) was measured by totaling somatic mutations per tumor. HER2 positivity through IHC and CISH was determined based on 2007 and 2018 ASCO/CAP HER2 breast cancer guidelines. RESULTS: There was a higher rate of HER2 positivity by IHC when using the 2018 guidelines compared to the 2007 guidelines (16.3% vs 12.3%). Concordance between IHC and CISH was 98.9%. ERBB2 amplification was identified by NGS in 10.5% of tumors. Compared to CISH results, this corresponds to a concordance rate of 91.6% and a positive predictive value (PPV) of 60.3%. Single gene alterations in HER2 amplified tumors that may implicate HER2 therapy resistance included PI3K (33.1%), KRAS (2.5%), and PTEN (1.3%). CONCLUSIONS: There was high concordance between HER2 positivity based on CISH and IHC. Rate of HER2 positivity is the lowest by NGS. Ultimately these testing platforms need to be validated by response to targeted therapy.

High visceral fat to subcutaneous fat ratios portend a poor prognosis in patients with advanced endometrial cancer.

OBJECTIVES: Visceral adiposity has been established as a predictor of outcomes in various cancers. We aimed to determine the association of radiographic measurements of visceral fat with clinical outcomes in patients with endometrial cancer. METHODS: A retrospective review of patients with stage III-IV endometrial cancer who underwent surgery between 2004 and 2014 was performed. Visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), and total adipose tissue (TAT;VAT+SAT) were assessed on preoperative computed tomography (CT) scans. Exploratory analysis was performed to establish the optimal cut-off values for VAT, SAT, and TAT to identify patients with poor prognostic body composition. Survival rates were analyzed using Kaplan-Meier analysis, log-rank tests, and cox-regression. RESULTS: Eighty-three patients were included. Forty-two (51%) patients had a low VAT/SAT ratio (<0.45) and 41 (49.4%) had a high VAT/SAT ratio (>0.45). There were no significant differences in demographics between the groups. The mean VAT, SAT, and TAT were 176.3 cm2, 379.3 cm2, and 555.3 cm2 respectively. Compared to patients with low VAT/SAT ratios, patients with high VAT/SAT ratios had a shorter recurrence-free survival (median 29.6 vs 32.3 months, P = 0.01) and shorter overall survival (median 56 vs 93.7 months, P = 0.03). CONCLUSIONS: Visceral fat measurements are predictive of outcomes in patients with advanced stage endometrial cancer. Specifically, VAT to SAT ratios are predictive of overall survival. Future studies should be pursued to identify potential therapeutic targets and biological mechanisms that underlie obesity's relationship with endometrial cancer.