A paradigm shift in understanding vulvovaginal melanoma as a distinct tumor type compared with cutaneous melanoma.

OBJECTIVE: Our goal was to compare molecular and immune profiles of vulvovaginal melanoma (VVM) with cutaneous melanoma (CM) and explore the significance of immune checkpoint inhibitor (ICI) agents on survival. METHODS: Samples from VVM and CM tumors underwent comprehensive molecular and immune profiling. Treatment and survival data were extracted from insurance claims data and OS was calculated from time of ICI treatment to last contact. Statistical significance was determined using chi-square and Wilcoxon rank sum test and adjusted for multiple comparisons. RESULTS: Molecular analysis was performed on 142 VVM and 3823 CM tumors. VVM demonstrated significantly (q < 0·01) less frequent BRAF and more frequent KIT, ATRX, and SF3B1 mutations. Alterations in pathways involving DNA damage and mRNA splicing were more common in VVM, while alterations in cell cycle and chromatin remodeling were less common. Immunogenicity of VVM was lower than CM, with an absence of high TMB (0% vs 46.9%) and lower PD-L1 positivity (18·0% vs 29·5%). Median immune checkpoint gene expression was lower in VVM, as were cell fractions for type I macrophages and CD8+ T-cells(q < 0·01). Myeloid dendritic cells were increased in VVM(q < 0·01). Median OS was shorter for VVM than for CM patients treated with ICIs (17·6 versus 37·9 months, HR:1·65 (95% CI 1·02-2·67) p = 0·04). CONCLUSIONS: VVM has a distinct molecular and immune profile compared to CM, which may contribute to the worse survival in VVM compared to CM patients treated with ICI therapy. Though ICIs have been a mainstay of treatment in recent years, our findings suggest that new therapeutic strategies are needed.

Phosphodiesterase 10A (PDE10A) as a novel target to suppress ß-catenin and RAS signaling in epithelial ovarian cancer.

A leading theory for ovarian carcinogenesis proposes that inflammation associated with incessant ovulation is a driver of oncogenesis. Consistent with this theory, nonsteroidal anti-inflammatory drugs (NSAIDs) exert promising chemopreventive activity for ovarian cancer. Unfortunately, toxicity is associated with long-term use of NSAIDs due to their cyclooxygenase (COX) inhibitory activity. Previous studies suggest the antineoplastic activity of NSAIDs is COX independent, and rather may be exerted through phosphodiesterase (PDE) inhibition. PDEs represent a unique chemopreventive target for ovarian cancer given that ovulation is regulated by cyclic nucleotide signaling. Here we evaluate PDE10A as a novel therapeutic target for ovarian cancer. Analysis of The Cancer Genome Atlas (TCGA) ovarian tumors revealed PDE10A overexpression was associated with significantly worse overall survival for patients. PDE10A expression also positively correlated with the upregulation of oncogenic and inflammatory signaling pathways. Using small molecule inhibitors, Pf-2545920 and a novel NSAID-derived PDE10A inhibitor, MCI-030, we show that PDE10A inhibition leads to decreased ovarian cancer cell growth and induces cell cycle arrest and apoptosis. We demonstrate these pro-apoptotic properties occur through PKA and PKG signaling by using specific inhibitors to block their activity. PDE10A genetic knockout in ovarian cancer cells through CRISP/Cas9 editing lead to decreased cell proliferation, colony formation, migration and invasion, and in vivo tumor growth. We also demonstrate that PDE10A inhibition leads to decreased Wnt-induced ß-catenin nuclear translocation, as well as decreased EGF-mediated activation of RAS/MAPK and AKT pathways in ovarian cancer cells. These findings implicate PDE10A as novel target for ovarian cancer chemoprevention and treatment.

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.

Molecular profiles of endometrial cancer tumors among Black patients.

OBJECTIVES: Disparate outcomes exist between Black and White patients with endometrial cancer (EC). One contributing factor is the disproportionately low representation of Black patients in clinical trials and in tumor molecular profiling studies. Our objective was to investigate molecular profiles of ECs in a cohort with a high proportion of tumors from Black patients. METHODS: A total of 248 EC samples and self-reported race data were collected from 6 institutions. Comprehensive tumor profiling and analyses were performed by Caris Life Sciences. RESULTS: Tumors from 105 (42%) Black and 143 (58%) White patients were included. Serous histology (58% vs 36%) and carcinosarcoma (25% vs 16%), was more common among Black patients, and endometrioid was less common (17% vs 48%) (p < 0.01). Differences in gene mutations between cohorts corresponded to observed histologic differences between races. Specifically, TP53 mutations were predominant in serous tumors. In endometrioid tumors, mutations in ARID1A were the most common, and high rates of MSI-H, MMRd, and TMB-H were observed. In carcinosarcoma tumors, hormone receptor expression was high in tumors of Black patients (PR 23.4%, ER 30.8%). When stratified by histology, there were no significant differences between tumors from Black and White women. CONCLUSIONS: This cohort had a high proportion of tumors from Black women. Distinct molecular profiles were driven primarily by more aggressive histologic subtypes among Black women. Continued effort is needed to include Black women and other populations under-represented in EC molecular profiling studies as targeted therapies and personalized medicine become mainstream.

Perivascular epithelioid cell tumor (PEComa) of the uterus: Challenges of pregnancy in determining prognosis and optimal treatment.

Background: Perivascular epithelioid cell tumor (PEComa) is a rare mesenchymal neoplasm that exhibits immunohistochemical evidence of smooth muscle and melanocytic differentiation.Case: We report a case of uterine PEComa in a 21 year-old primigravida, presenting at time of c-section as a small subserosal lesion that expressed soft tan-brown tissue fragments. Microscopically the cells were epithelioid, staining positive for TFE3 and HMB45. Significant cytologic atypia and mitotic activity were concerning for malignancy. The patient was treated post-partum with total robotic hysterectomy and right salpingo-oopherectomy, and is currently without evidence of disease. Conclusion: This case of PEComa diagnosed during pregnancy highlights the importance of intra-operative biopsy and the difficulty of predicting malignant potential of PEComa in the setting of a gravid uterus with a dynamic smooth muscle architecture.

A novel proteomic-based screening method for ovarian cancer using cervicovaginal fluids: A window into the abdomen.

OBJECTIVE: Our objective is to develop a site-specific proteomic-based screening test for ovarian cancer(OC) using the mucus of the cervix and vagina and evaluate a potential means for home testing. METHODS: Cervicovaginal fluid samples were obtained from ovarian cancer and normal control patients for LC-mass spectrometry(MS) proteomic evaluation. Statistical modeling determined the protein panel with the highest penetrance across ovarian cancer samples. A subcohort of patients consented to provide self-collected vaginal samples at home with questionnaire on feasibility. Cohen's kappa methodology was utilized to determine agreement between physician-collected and patient-collected samples. RESULTS: A total of 83 consecutive patient samples were collected prospectively (33 ovarian cancer & 50 controls). Thirty patients consented for self-collection. Using LC-MS, 30 peptides demonstrated independent statistical significance for detecting ovarian cancer. Using statistical modeling, the protein panel that determined the best predictor for detecting OC formed a "fingerprint" consisting of 5 proteins: serine proteinase inhibitor A1; periplakin; profilin1; apolipoprotein A1; and thymosin beta4-like protein. These peptides demonstrated a significant increase probability of detecting ovarian cancer with the ROC curve having an AUC of 0.86 (p = 0.00001). Physician-collected and patient-collected specimens demonstrated moderate agreement with kappa average of 0.6 with upper bound of 0.75. CONCLUSIONS: Using novel site-specific collection methods, we identified an OC "fingerprint" with adequate sensitivity and specificity to warrant further evaluation in a larger cohort. Agreement of physician-collected and patient-collected samples were encouraging and could improve access to screening with a home self-collection if this screening test is validated in future studies.

Health Care Provider Adherence to Surgical Guidelines for Risk-Reducing Salpingo-Oophorectomy.

OBJECTIVE: To evaluate health care provider adherence to the surgical protocol endorsed by the National Comprehensive Cancer Network and the American College of Obstetricians and Gynecologists at the time of risk-reducing salpingo-oophorectomy and compare adherence between gynecologic oncologists and obstetrician-gynecologists (ob-gyns). METHODS: In this multicenter retrospective cohort study, women were included if they had a pathogenic BRCA mutation and underwent risk-reducing salpingo-oophorectomy between 2011 and 2017. Adherence was defined as completing all of the following: collection of washings, complete resection of the fallopian tube, and performing the Sectioning and Extensively Examining the Fimbriated End (SEE-FIM) pathologic protocol. RESULTS: Of 290 patients who met inclusion criteria, 160 patients were treated by 18 gynecologic oncologists and 130 patients by 75 ob-gyns. Surgery was performed at 10 different hospitals throughout a single metropolitan area. Demographic and clinical characteristics were similar between groups. Overall, 199 cases (69%) were adherent to the surgical protocol. Gynecologic oncologists were more than twice as likely to fully adhere to the full surgical protocol as ob-gyns (91% vs 41%, P<.01). Specifically, gynecologic oncologists were more likely to resect the entire tube (99% vs 95%, P=.03), to have followed the SEE-FIM protocol (98% vs 82%, P<.01), and collect washings (94% vs 49%, P<.01). Complication rates did not differ between groups. Occult neoplasia was diagnosed in 11 patients (3.8%). The incidence of occult neoplasia was 6.3% in gynecologic oncology patients and 0.8% in obstetrics and gynecology patients (P=.03). CONCLUSION: Despite clear surgical guidelines, only two thirds of all health care providers were fully adherent to guidelines. Gynecologic oncologists were more likely to follow surgical guidelines compared with general ob-gyns and more likely to diagnose occult neoplasia despite similar patient populations. Rates of risk-reducing surgery will likely continue to increase as genetic testing becomes more widespread, highlighting the importance of health care provider education for this procedure. Centralized care or referral to subspecialists for risk-reducing salpingo-oophorectomy may be warranted.