Novel Androgen Receptor Splice Variant 7 in Gynecologic Tumors.

Androgen receptor splicing variant 7 (AR-V7) is a truncated variant of the AR mRNA that may be a predictive biomarker for AR-targeted therapy. AR-V7 has been described in prostate, breast, salivary duct, and hepatocellular carcinomas as well as mammary and extra-mammary Paget disease. We report 2 gynecologic cancers occurring in the lower uterine segment and ovary and both harboring AR-V7 by targeted RNA sequencing. The uterine tumor was an undifferentiated carcinoma consisting of epithelioid cells and focally spindled cells arranged in sheets, nests, and cords associated with brisk mitotic activity and tumor necrosis. The ovarian tumor consisted of glands with cribriform and solid architecture and uniform cytologic atypia. ER and PR were positive in the ovarian tumor and negative in the uterine tumor. Both were positive for AR and negative for HER2, GATA3, and NKX3.1. DNA methylation profiling showed epigenetic similarity of the AR-V7-positive gynecologic cancers to AR-V7-positive breast cancers rather than to prostate cancers. AR-V7 may underpin rare gynecologic carcinomas with undifferentiated histology or cribriform growth reminiscent of prostatic adenocarcinoma and breast invasive ductal carcinoma.

Nivolumab for mismatch-repair-deficient or hypermutated gynecologic cancers: a phase 2 trial with biomarker analyses.

Programmed death-1 (PD-1) inhibitors are approved for therapy of gynecologic cancers with DNA mismatch repair deficiency (dMMR), although predictors of response remain elusive. We conducted a single-arm phase 2 study of nivolumab in 35 patients with dMMR uterine or ovarian cancers. Co-primary endpoints included objective response rate (ORR) and progression-free survival at 24 weeks (PFS24). Secondary endpoints included overall survival (OS), disease control rate (DCR), duration of response (DOR) and safety. Exploratory endpoints included biomarkers and molecular correlates of response. The ORR was 58.8% (97.5% confidence interval (CI): 40.7-100%), and the PFS24 rate was 64.7% (97.5% one-sided CI: 46.5-100%), meeting the pre-specified endpoints. The DCR was 73.5% (95% CI: 55.6-87.1%). At the median follow-up of 42.1 months (range, 8.9-59.8 months), median OS was not reached. One-year OS rate was 79% (95% CI: 60.9-89.4%). Thirty-two patients (91%) had a treatment-related adverse event (TRAE), including arthralgia (n = 10, 29%), fatigue (n = 10, 29%), pain (n = 10, 29%) and pruritis (n = 10, 29%); most were grade 1 or grade 2. Ten patients (29%) reported a grade 3 or grade 4 TRAE; no grade 5 events occurred. Exploratory analyses show that the presence of dysfunctional (CD8+PD-1+) or terminally dysfunctional (CD8+PD-1+TOX+) T cells and their interaction with programmed death ligand-1 (PD-L1)+ cells were independently associated with PFS24. PFS24 was associated with presence of MEGF8 or SETD1B somatic mutations. This trial met its co-primary endpoints (ORR and PFS24) early, and our findings highlight several genetic and tumor microenvironment parameters associated with response to PD-1 blockade in dMMR cancers, generating rationale for their validation in larger cohorts.ClinicalTrials.gov identifier: NCT03241745 .

Adverse events and oncologic outcomes with combination lenvatinib and pembrolizumab for the treatment of recurrent endometrial cancer.

OBJECTIVE: To evaluate adverse events (AEs) of combination lenvatinib plus pembrolizumab for the treatment of recurrent endometrial cancer (EC) and to assess outcomes by lenvatinib starting dose. METHODS: We retrospectively reviewed patients with recurrent EC treated with lenvatinib plus pembrolizumab at our institution between 10/1/2019-11/30/2021. Starting dose of lenvatinib was defined as standard (20 mg) or reduced (10 mg/14 mg). AEs were manually extracted through chart review and graded using Common Terminology Criteria for Adverse Events (CTCAE) version 5.0. PFS, overall survival (OS), and duration of response (DOR) were analyzed. RESULTS: Forty-three patients were identified; median age was 67 years (range, 54-85). The most common histologies were serous (35%), endometrioid (23%), and carcinosarcoma (21%). Starting lenvatinib doses were 10 mg (n = 10), 14 mg (n = 10), and 20 mg (n = 23). Median number of cycles received was 8 (range, 1-42). Twenty-four patients (56%) required ≥1 lenvatinib dose reduction; 3 (7%) discontinued lenvatinib, and 1 (2%) discontinued pembrolizumab for intolerance or AE. Thirty-six patients (84%) experienced grade ≥ 3 AEs; hypertension, weight loss, anemia, fatigue, and thrombocytopenia were most common. The standard dose group experienced significantly shorter observed PFS vs the reduced dose group (P = .02). There was no difference in DOR (P = .09) or OS (P = .27) between the groups. CONCLUSION: In clinical practice, AEs associated with combination lenvatinib plus pembrolizumab were common and comparable to Study 309/KEYNOTE-775 findings. AEs were similar regardless of starting lenvatinib dose. Further dose optimization studies of lenvatinib plus pembrolizumab may be indicated in recurrent EC. Clinical trial data remain the gold standard to guide starting lenvatinib dosing.

Durvalumab with or without tremelimumab in patients with persistent or recurrent endometrial cancer or endometrial carcinosarcoma: A randomized open-label phase 2 study.

INTRODUCTION: Our understanding of the biologic heterogeneity of endometrial cancer has improved, but which patients benefit from single-agent versus combination immune checkpoint blockade remains unclear. METHODS: We conducted a single-center, randomized, open-label, phase 2 study of durvalumab 1500 mg (Arm 1) versus durvalumab 1500 mg plus tremelimumab 75 mg every 4 weeks (Arm 2) in patients with endometrial carcinoma. The primary endpoints were overall response rate (ORR) and progression-free survival (PFS) at 24 weeks. Patients were stratified by mismatch repair (MMR) status and carcinosarcoma histology. Using a Simon two-stage minimax design, we determined 40 patients per arm would provide 90% power and Type 1 error of 10%. RESULTS: Eighty-two patients were enrolled; 77 were evaluable for toxicity (Arm 1: 38, Arm 2: 39) and 75 evaluable for efficacy (Arm 1: 37, Arm 2: 38). Patient were stratified by MMR status (Arm 1: 5, Arm 2: 4 were MMR-deficient). The ORR in Arm 1 was 10.8% (one-sided 90% CI: 4.8-100%); the ORR in Arm 2 was 5.3% (one-sided 90% CI: 1.4-100%). Since the primary endpoint of ORR was not met, 24-week PFS was not compared to historical controls per protocol specification. No new safety signals were identified. CONCLUSIONS: In these patients with predominantly MMR-proficient endometrial cancer, there was limited response with single-agent and combined immune checkpoint blockade. The pre-specified efficacy thresholds were not met for further evaluation. A deeper understanding of potential mechanisms of resistance to immunotherapy in MMR-proficient endometrial cancer is needed for the development of novel therapeutic approaches.

Management of patients with early-stage ovarian clear cell carcinoma: risk stratification and fertility conservation.

OBJECTIVE: We sought to describe clinicopathologic and treatment factors associated with oncologic outcomes in patients with early-stage ovarian clear cell carcinoma undergoing complete staging and in a sub-set of these patients undergoing fertility-conserving surgery. METHODS: We retrospectively identified patients with ovarian clear cell carcinoma initially treated at our institution from January 1, 1996 to March 31, 2020. Survival was estimated using Kaplan-Meier curves and compared by log-rank test. Survival-associated variables were identified by Cox proportional hazards regression. RESULTS: Of 182 patients, mismatch repair and p53 protein expression were assessed by immunohistochemistry on 82 and 66 samples, respectively. There were no significant differences in progression-free survival or overall survival between mismatch repair-deficient (n=6, including 4 patients with Lynch syndrome; 7.3%) and mismatch repair-proficient patients, whereas aberrant p53 expression (n=3; 4.5%) was associated with worse progression-free (p<0.001) and overall survival (p=0.01). Patients with stage IA/IC1 disease had a 95% 5-year overall survival rate (95% CI 88% to 98%); patients with stage IC2/IC3 disease had a similar 5-year overall survival rate (76%; 95% CI 54% to 88%) to that of patients with stage IIA/IIB disease (82%; 95% CI 54% to 94%). There was no difference in 5-year overall survival in patients with stage IA/IC1 undergoing chemotherapy versus observation (94% vs 100%). Nine patients underwent fertility-sparing surgery and none experienced recurrence. Of five patients who pursued fertility, all had successful pregnancies. CONCLUSIONS: In patients with completely staged ovarian clear cell carcinoma, those with stage IA/IC1 disease have an excellent prognosis, regardless of chemotherapy. Aberrant p53 expression may portend worse outcomes. Additional investigation is warranted on the safety of fertility conservation in patients with stage IA/IC1 disease.

Microsatellite Instability-High Endometrial Cancers with MLH1 Promoter Hypermethylation Have Distinct Molecular and Clinical Profiles.

PURPOSE: Microsatellite instability-high (MSI-H) endometrial carcinomas are underpinned by distinct mechanisms of DNA mismatch repair deficiency (MMR-D). We sought to characterize the clinical and genetic features of MSI-H endometrial cancers harboring germline or somatic mutations in MMR genes or MLH1 promoter hypermethylation (MLH1ph). EXPERIMENTAL DESIGN: Of > 1,100 patients with endometrial cancer that underwent clinical tumor-normal sequencing, 184 had MSI-H endometrial cancers due to somatic MMR mutations or MLH1ph, or harbored pathogenic germline MMR mutations. Clinicopathologic features, mutational landscape, and tumor-infiltrating lymphocyte (TIL) scores were compared among MMR-D groups using nonparametric tests. Log-rank tests were used for categorical associations; Kaplan-Meier method and Wald test based on Cox proportional hazards models were employed for continuous variables and survival analyses. RESULTS: Compared with patients with germline (n = 25) and somatic (n = 39) mutations, patients with MLH1ph endometrial cancers (n = 120) were older (P < 0.001), more obese (P = 0.001) and had more advanced disease at diagnosis (P = 0.025). MLH1ph endometrial cancers were enriched for JAK1 somatic mutations as opposed to germline MMR-D endometrial cancers which showed enrichment for pathogenic ERBB2 mutations. MLH1ph endometrial cancers exhibited lower tumor mutational burden and TIL scores compared with endometrial cancers harboring germline or somatic MMR mutations (P < 0.01). MLH1ph endometrial cancer patients had shorter progression-free survival (PFS) on univariate analysis, but in multivariable models, stage at diagnosis remained the only predictor of survival. For stage I/II endometrial cancer, two-year PFS was inferior for patients with MLH1ph endometrial cancers compared with germline and somatic MMR groups (70% vs. 100%, respectively). CONCLUSIONS: MLH1ph endometrial cancers likely constitute a distinct clinicopathologic entity compared with germline and somatic MMR-D ECs with potential treatment implications.

Baseline risk of hematologic malignancy at initiation of frontline PARP inhibitor maintenance for BRCA1/2-associated ovarian cancer.

Poly(ADP-ribose) polymerase inhibitors (PARPi) are FDA approved as frontline maintenance for BRCA-associated advanced stage high-grade ovarian cancer (HGOC), having demonstrated an unprecedented improvement in relapse-free survival. Myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML) are rare toxicities of PARPi. We describe three patients with germline BRCA-associated (gBRCA+) HGOC and alterations in AML driver genes. Although none evidenced overt hematologic malignancy, PARPi maintenance was cautiously considered given the potential risk of MDS/AML. A better understanding of the role of clonal hematopoiesis in the subsequent development of PARPi-associated MDS/AML will improve management of this patient population.

Sustained response to lenvatinib and pembrolizumab in two patients with KRAS-mutated endometrial mesonephric-like adenocarcinoma.

•Endometrial mesonephric-like adenocarcinoma (MLA) is a rare and aggressive subtype of epithelial endometrial cancer.•KRAS mutations are characteristic in patients with endometrial MLA.•We report two cases of KRAS-mutated endometrial MLA with excellent and durable responses to lenvatinib and pembrolizumab.•Tumors with KRAS mutations may be particularly sensitive to lenvatinib, but this warrants further study.

Targeting obesity-related dysfunction in hormonally driven cancers.

Obesity is a risk factor for at least 13 different types of cancer, many of which are hormonally driven, and is associated with increased cancer incidence and morbidity. Adult obesity rates are steadily increasing and a subsequent increase in cancer burden is anticipated. Obesity-related dysfunction can contribute to cancer pathogenesis and treatment resistance through various mechanisms, including those mediated by insulin, leptin, adipokine, and aromatase signalling pathways, particularly in women. Furthermore, adiposity-related changes can influence tumour vascularity and inflammation in the tumour microenvironment, which can support tumour development and growth. Trials investigating non-pharmacological approaches to target the mechanisms driving obesity-mediated cancer pathogenesis are emerging and are necessary to better appreciate the interplay between malignancy, adiposity, diet and exercise. Diet, exercise and bariatric surgery are potential strategies to reverse the cancer-promoting effects of obesity; trials of these interventions should be conducted in a scientifically rigorous manner with dose escalation and appropriate selection of tumour phenotypes and have cancer-related clinical and mechanistic endpoints. We are only beginning to understand the mechanisms by which obesity effects cell signalling and systemic factors that contribute to oncogenesis. As the rates of obesity and cancer increase, we must promote the development of non-pharmacological lifestyle trials for the treatment and prevention of malignancy.

Bevacizumab in advanced endometrial cancer.

OBJECTIVE: Prospective data have demonstrated the efficacy of bevacizumab monotherapy in the treatment of advanced endometrial cancer. Bevacizumab is used off-label, and real-world data regarding the role of bevacizumab in endometrial cancer treatment are scant. In this largest single-institution retrospective study of its kind, we report our experience with bevacizumab monotherapy in the treatment of advanced/recurrent endometrial cancer. METHODS: All eligible patients (n = 101) had histologically confirmed endometrial cancer and were treated with bevacizumab at our institution from 2004 to 2017. Demographic data and tumor characteristics were obtained through chart review. Primary objective was response to therapy determined by Response Evaluation Criteria in Solid Tumors (RECIST v1.1). RESULTS: Analysis included 13 grade 1/2 endometrioid, 15 grade 3 endometrioid, 44 serous, 8 carcinosarcoma, and 21 other/mixed histologies. No patients achieved complete (CR) or partial (PR) responses; 19 achieved stable disease (SD). The clinical benefit rate (CBR; CR + PR + SD) was 19% (95% CI: 12-28%). The CBRs were 7%, 17%, 21%, and 23% for patients with 1, 2, 3, and ≥ 4 prior treatment lines. Median PFS ranged from 2.6 months (2 lines) to 4.9 months (≥4 lines). The 3-year OS rate was 58% (95% CI: 47-67%). The median OS was 3.4 years (95% CI: 2.9-4.2), ranging from 2.5 years (2 lines) to 4.5 years (≥4 lines). The most common treatment-related adverse event was hypertension; 35 (78%) of 45 were grade 1 or 2. CONCLUSIONS: In heavily pretreated advanced endometrial cancer, bevacizumab was associated with modest clinical efficacy and remains a viable palliative option in this setting.

A phase I open-label study of selinexor with paclitaxel and carboplatin in patients with advanced ovarian or endometrial cancers.

PURPOSE: Selinexor, a selective inhibitor of nuclear export, monotherapy causes nuclear accumulation of tumor-suppressor proteins and has anti-tumor activity in ovarian and endometrial cancers. The safety and tolerability of oral selinexor plus intravenous carboplatin and paclitaxel chemotherapy (selinexor + CP) was evaluated in this population. PATIENTS AND METHODS: This phase I, 3 + 3 dose-escalation study assessed 4 selinexor + CP regimens. Patients in cohorts of 3, regardless of disease type, were administered 1 of 4 alternating regimens (selinexor at 30 mg/m2 or 60 mg plus CP at AUC 5 and 175 mg/m2 or 80 mg/m2, respectively) for 6-10 cycles (1 cycle = 21 days), followed by selinexor maintenance. Enrolled patients with ovarian cancer had received 1 prior platinum-based therapy. Patients with endometrial cancer were chemotherapy-naive or had received 1 prior platinum-based therapy. Response was evaluated every 9 weeks. RESULTS: Twenty-three patients were treated (5 serous ovarian cancer; 18 endometrial cancer, including 6 carcinosarcomas). The most common treatment-related adverse events (TRAEs) were thrombocytopenia (100%), leukopenia (91%), and hyperglycemia (87%). The most common grade 3/4 TRAEs were leukopenia (70%), neutropenia (70%), lymphopenia (61%), anemia (57%), and alanine transaminase increase (43%). One treatment-related dose-limiting toxicity (grade 3 syncope) occurred. Twelve patients achieved a partial response and 1 achieved a complete response. Responses to all four regimens were observed in ovarian and endometrial cancers. CONCLUSIONS: Combination selinexor + CP was safe and tolerated in advanced ovarian and endometrial cancers.

Management of thymoma-associated pure red cell aplasia: A novel use of blood substitute HBOC-201 in a Jehovah's Witness.

Pure red cell aplasia (PRCA) is a rare paraneoplastic syndrome occasionally associated with thymomas. Here, we report on the first ever use of a bovine hemoglobin-based oxygen carrier, HBOC-201 (HbO2 Therapeutics LLC; Hemopure®, Waltham, MA) for the supportive management of pure red cell aplasia in a Jehovah Witness patient.

Phase 2 study of LY3023414 in patients with advanced endometrial cancer harboring activating mutations in the PI3K pathway.

BACKGROUND: PI3K pathway activation is common in endometrial cancer. We evaluated the safety and efficacy of the dual PI3K/mTOR inhibitor, LY3023414, in patients with advanced endometrial cancer harboring activating mutations in the PI3K pathway. METHODS: We conducted a single-arm phase 2 study of monotherapy LY3023414. Eligible patients had advanced endometrial cancer of any grade, prior management with 1-4 cytotoxic lines, and PI3K pathway activation prospectively defined as a loss-of-function PTEN alteration or activating alteration in PIK3CA, AKT1, PIK3R1, PIK3R2, or MTOR. The primary objective was best overall response rate (ORR) per RECIST 1.1. RESULTS: Twenty-eight patients were treated; histologies included endometroid (39%), carcinosarcoma (25%), serous (21%), and mixed (14%). Patients were heavily pretreated, with a median of 2 prior cytotoxic lines (range, 1-3). The most common alterations involved PIK3CA (68%), PTEN (43%), and PIK3R1 (32%). In the 25 efficacy-evaluable patients, the ORR was 16% (90% CI, 7%-100%), and the clinical benefit rate was 28% (90% CI, 16%-100%). Four patients had a confirmed partial response, and 2 responses lasted for >9 months. The median progression-free survival and overall survival were 2.5 months (95% CI, 1.2-3.0) and 9.2 months (95% CI, 5.0-15.9), respectively. The most common all-grade treatment-related adverse events were anemia (71%), hyperglycemia (71%), hypoalbuminemia (68%), and hypophosphatemia (61%). No correlation between molecular alterations and response was observed. CONCLUSION: In patients with heavily pretreated advanced endometrial cancer prospectively selected for tumors with activating PI3K pathway mutations, LY3023414 demonstrated modest single-agent activity and a manageable safety profile.

Optimizing immunotherapy for gynecologic cancers.

PURPOSE OF REVIEW: This review will provide an update on the most recent clinical developments in immuno-oncology in advanced gynecologic cancers and will also highlight ongoing studies in this field. RECENT FINDINGS: Although immune checkpoint blockade (ICB) therapy is rapidly altering the treatment landscape in a myriad of solid tumors, the efficacy of ICB therapy with antibodies directed against CTLA-4, PD-1, and PD-L1 in advanced gynecologic cancers has been limited. The exception has been the PD-1 inhibitor pembrolizumab in microsatellite instability high (MSI-H) or mismatch repair-deficient (dMMR) advanced endometrial cancers, highlighted by the recent conditional approval of pembrolizumab in recurrent/metastatic PD-L1-positive cervical cancers and the accelerated approval of pembrolizumab and lenvatinib in microsatellite stable (MSS) or mismatch repair-proficient (pMMR) advanced endometrial cancer. The discovery of novel, rational ICB combinatorial approaches in advanced gynecologic cancers is highly warranted. SUMMARY: Recent advances in the genomic characterization of gynecologic malignancies have informed clinical trial design. However, improved molecular and immunophenotypic biomarkers to more accurately identify patients who will most benefit from immunotherapeutic approaches are urgently needed. This is especially critical as we attempt to integrate immune-oncology agents, chemotherapy, targeted therapy, and radiation therapy in the management of gynecologic cancers.

Clinical outcomes of patients with POLE mutated endometrioid endometrial cancer.

OBJECTIVES: Assess outcomes of a clinical cohort of patients with endometrioid endometrial cancer (EEC) harboring somatic POLE exonuclease domain mutations (EDMs). METHODS: Patients were consented to a protocol of tumor-normal massively parallel sequencing of 410-468 cancer related genes. EECs subjected to sequencing from 2014 to 2018 were reviewed. Tumors with somatic POLE EDMs were identified. EECs were assessed for microsatellite instability (MSI) using MSIsensor and immunohistochemical analysis for mismatch repair (MMR) proteins. RESULTS: Of the 451 EECs sequenced, 23 had a POLE EDM (5%): 20 primary and 3 recurrent tumors sequenced. Nineteen cases (83%) were stage I/II and 4 (17%) were stages III/IV. Thirteen EECs (57%) were of FIGO grades 1/2, 10 (43%) grade 3. All patients were treated with surgery and 17 (89%) received adjuvant therapy. Five (22%) demonstrated loss of DNA MMR protein expression, none were due to Lynch syndrome. MSIsensor scores were conclusive for 21 samples: 19 were microsatellite stable and 2 MSI-high. After median follow-up of 30 months, 4/23 (17%) developed recurrences: 3 with initial grade 3 stage I and 1 with grade 1 stage III disease. One patient with grade 2 stage IV EEC had progressive disease after treatment. CONCLUSIONS: Patients with POLE EDM EEC have been shown to have a favorable prognosis. In this real-world cohort of patients, de novo metastatic disease and recurrences in initially uterine-confined cases were observed. Further research is warranted before incorporating the presence of POLE EDM into decision-making regarding adjuvant therapy.

Bridging therapy effectiveness in the treatment of hepatocellular carcinoma prior to orthotopic liver transplantation.

BACKGROUND: Orthotopic liver transplantation (OLT) is the most effective treatment for hepatocellular carcinoma (HCC) in patients with underlying cirrhosis and portal hypertension. Availability of OLT is limited by donor-organ shortages, which increase patient waiting time until OLT. A variety of bridging therapies (BT) have been used to halt tumor progression in patients on the OLT waiting list. Despite complete radiologic responses following BT, viable tumor is often present in explants. METHODS: Treatment outcomes were evaluated in 50 patients who had a total of 125 BT for treatment of 93 nodules. Success of BT was assessed by radiologic response compared to histopathological examination of explanted livers. RESULTS: Pre-transplant treatments included: transcatheter arterial chemoembolization (TACE), alcohol ablation (ETOH), radiofrequency ablation (RFA), microwave ablation (MWA), selective internal radiation therapy (SIRT) and stereotactic body radiation therapy (SBRT). Fifty-nine (64%) nodules had a complete radiographic response to therapy; however, only 28 nodules (30%) had complete tumor necrosis (CTN) on explant examination. Ten nodules with CTN were treated with TACE alone. Seven of the 28 nodules with CTN were treated with TACE and RFA. Three of seven nodules treated with TACE and SIRT had CTN. Patients underwent a mean of 2.5 BTs. Six of 50 patients (12%) had no residual HCC in their explants. Five of those six patients (83%) had complete response (CR) on pre-transplant imaging. CONCLUSIONS: Although favorable radiologic responses are seen following BT, viable HCC is seen in the majority of liver explants and radiographic imaging cannot always accurately predict pathological response. This underscores the need for aggressive treatment of patients who otherwise may not be eligible for OLT.