Adenoid cystic carcinoma of the Bartholin's gland is underpinned by MYB- and MYBL1- rearrangements.

OBJECTIVE: Adenoid cystic carcinoma (AdCC) of the Bartholin's gland (AdCC-BG) is a very rare gynecologic vulvar malignancy. AdCC-BGs are slow-growing but locally aggressive and are associated with high recurrence rates. Here we sought to characterize the molecular underpinning of AdCC-BGs. METHODS: AdCC-BGs (n = 6) were subjected to a combination of RNA-sequencing, targeted DNA-sequencing, reverse-transcription PCR, fluorescence in situ hybridization (FISH) and MYB immunohistochemistry (IHC). Clinicopathologic variables, somatic mutations, copy number alterations and chimeric transcripts were assessed. RESULTS: All six AdCC-BGs were biphasic, composed of ductal and myoepithelial cells. Akin to salivary gland and breast AdCCs, three AdCC-BGs had the MYB::NFIB fusion gene with varying breakpoints, all of which were associated with MYB overexpression by IHC. Two AdCC-BGs were underpinned by MYBL1 fusion genes with different gene partners, including MYBL1::RAD51B and MYBL1::EWSR1 gene fusions, and showed MYB protein expression. Although the final AdCC-BG studied had MYB protein overexpression, no gene fusion was identified. AdCC-BGs harbored few additional somatic genetic alterations, and only few mutations in cancer-related genes were identified, including GNAQ, GNAS, KDM6A, AKT1 and BCL2, none of which were recurrent. Two AdCC-BGs, both with a MYB::NFIB fusion gene, developed metastatic disease. CONCLUSIONS: AdCC-BGs constitute a convergent phenotype, whereby activation of MYB or MYBL1 can be driven by the MYB::NFIB fusion gene or MYBL1 rearrangements. Our observations further support the notion that AdCCs, irrespective of organ site, constitute a genotypic-phenotypic correlation. Assessment of MYB or MYBL1 rearrangements may be used as an ancillary marker for the diagnosis of AdCC-BGs.

Prognostic value of isolated tumor cells in sentinel lymph nodes in low risk endometrial cancer: results from an international multi-institutional study.

OBJECTIVE: The prognostic significance of isolated tumor cells (≤0.2 mm) in sentinel lymph nodes (SLNs) of endometrial cancer patients is still unclear. Our aim was to assess the prognostic value of isolated tumor cells in patients with low risk endometrial cancer who underwent SLN biopsy and did not receive adjuvant therapy. Outcomes were compared with node negative patients. METHODS: Patients with SLNs-isolated tumor cells between 2013 and 2019 were identified from 15 centers worldwide, while SLN negative patients were identified from Mayo Clinic, Rochester, between 2013 and 2018. Only low risk patients (stage IA, endometrioid histology, grade 1 or 2) who did not receive any adjuvant therapy were included. Primary outcomes were recurrence free, non-vaginal recurrence free, and overall survival, evaluated with Kaplan-Meier methods. RESULTS: 494 patients (42 isolated tumor cells and 452 node negative) were included. There were 21 (4.3%) recurrences (5 SLNs-isolated tumor cells, 16 node negative); recurrence was vaginal in six patients (1 isolated tumor cells, 5 node negative), and non-vaginal in 15 (4 isolated tumor cells, 11 node negative). Median follow-up among those without recurrence was 2.3 years (interquartile range (IQR) 1.1-3.0) and 2.6 years (IQR 0.6-4.2) in the SLN-isolated tumor cell and node negative patients, respectively. The presence of SLNs-isolated tumor cells, lymphovascular space invasion, and International Federation of Obstetrics and Gynecology (FIGO) grade 2 were significant risk factors for recurrence on univariate analysis. SLN-isolated tumor cell patients had worse recurrence free survival (p<0.01) and non-vaginal recurrence free survival (p<0.01) compared with node negative patients. Similar results were observed in the subgroup of patients without lymphovascular space invasion (n=480). There was no difference in overall survival between the two cohorts in the full sample and the subset excluding patients with lymphovascular space invasion. CONCLUSIONS: Patients with SLNs-isolated tumor cells and low risk profile, without adjuvant therapy, had a significantly worse recurrence free survival compared with node negative patients with similar risk factors, after adjusting for grade and excluding patients with lymphovascular space invasion. However, the presence of SLNs-isolated tumor cells was not associated with worse overall survival.

LCK facilitates DNA damage repair by stabilizing RAD51 and BRCA1 in the nucleus of chemoresistant ovarian cancer.

Poly-ADP Ribose Polymerase (PARP) targeted therapy is clinically approved for the treatment of homologous recombination (HR) repair deficient tumors. The remarkable success of this therapy in the treatment of HR repair deficient cancers has not translated to HR-proficient cancers. Our studies identify the novel role of non-receptor lymphocyte-specific protein tyrosine kinase (LCK) in the regulation of HR repair in endometrioid epithelial ovarian cancer (eEOC) model. We show that DNA damage leads to direct interaction of LCK with the HR repair proteins RAD51 and BRCA1 in a kinase dependent manner RAD51 and BRCA1 stabilization. LCK expression is induced and activated in the nucleus in response to DNA damage insult. Disruption of LCK expression attenuates RAD51, BRCA1, and BRCA2 protein expression by hampering there stability and results in inhibition of HR-mediated DNA repair including suppression of RAD51 foci formation, and augmentation of γH2AX foci formation. In contrast LCK overexpression leads to increased RAD51 and BRCA1 expression with a concomitant increase in HR DNA damage repair. Importantly, attenuation of LCK sensitizes HR-proficient eEOC cells to PARP inhibitor in cells and pre-clinical mouse studies. Collectively, our findings identify a novel therapeutic strategy to expand the utility of PARP targeted therapy in HR proficient ovarian cancer.

HER2 IHC Expression and Gene Amplification in p53-aberrant High-grade Endometrial Endometrioid Carcinoma Suggests That This Population May Benefit From HER2 Testing and Targeted Therapy.

Among gynecologic cancers, uterine serous carcinoma (USC) has been shown to be human epidermal growth factor receptor 2 (HER2) amplified and trastuzumab has been included in the recent National Comprehensive Cancer Network (NCCN) guidelines for treatment of advanced stage or recurrent USC with HER2 overexpression/amplification. There is limited literature suggesting that a subset of high-grade endometrioid carcinomas with aberrant p53 expression may also be HER2 amplified and these patients could benefit from the addition of targeted therapy. We identified 59 p53-aberrant (mismatch repair proficient) FIGO 3 endometrioid carcinomas of the uterus. HER2 immunohistochemistry was performed in all 59 tumors and HER2 fluorescence in situ hybridization (FISH) was performed in 52 of the 59 cases. Four of the 59 cases were HER2 3+ by immunohistochemistry (6.7%), using the American Society of Clinical Oncology/College of American Pathologists (ASCO/CAP) 2007, 2013, and 2018 criteria. HER2 FISH was performed in 3 of the 4 cases and was amplified in all 3. Nine, 8, and 7 tumors showed 2+ HER2 staining when applying 2018, 2013, and 2007 criteria, respectively, FISH was performed in 7 tumors and none were amplified. An additional 4 cases did not perfectly meet the 2018 ASCO/CAP criteria but were assigned a score of 2+, none were amplified by HER2 FISH. The remaining 42 cases showed 1+ or no staining for HER2, FISH was successfully performed in 38 tumors and none showed amplification. Approximately half of the tumors fulfilled criteria for HER2-low or HER2-very low (10 HER2-low and 20 HER2-very low). Our data shows that a subset of p53-aberrant high-grade endometrial endometrioid carcinoma express HER2 and these patients may benefit from the addition of targeted therapy. The role of targeted therapy in HER2-low gynecologic carcinoma is currently unexplored.

Evaluation of Lineage/Site-specific Nuclear Immunohistochemical Markers SATB2, Cyclin D1, SALL4, and BCOR in High-grade Endometrial Carcinomas.

Poorly differentiated malignant neoplasms involving the gynecologic tract routinely include a poorly differentiated endometrial carcinoma (EC) in the differential diagnosis. Some nuclear lineage/site-specific immunohistochemical markers are utilized in this diagnostic setting including SATB2, cyclin D1, SALL4, and BCOR, but their specificity and use in small samples are not clear across the spectrum of ECs. Cases of undifferentiated/dedifferentiated endometrial carcinomas (UEC/DDEC), clear cell carcinoma (CCC), uterine serous carcinoma (USC), FIGO grade 3 endometrial endometrioid carcinoma (EEC), and uterine carcinosarcoma (UCS) were identified and diagnoses confirmed. Whole-section immunohistochemical stains for SATB2, cyclin D1, SALL4, BCOR, and PAX8 were performed. A total of 113 cases were utilized: 15 CCC, 26 EEC, 19 UCS, 22 USC, and 31 UEC/DDEC. Cases were distributed across both low (49%) and high (51%) FIGO clinical stages. SATB2 was expressed by UCS (8/19, 42%), EEC (10/26, 38%), UEC/DDEC (11/30, 37%), and USC (6/22, 27%). Cyclin D1 was expressed by EEC (24/26, 92%), USC (17/22, 77%), UEC/DDEC (15/20 EEC component, 75%; 22/30 UEC, 73%), UCS (10/16 carcinoma, 63%; 11/19 sarcoma, 58%), and CCC (8/15, 53%). SALL4 was expressed most frequently by UEC/DDEC (12/30, 40%), but also USC (7/22, 32%), EEC (5/26, 19%), and UCS (4/16 carcinoma, 25%; 3/19 sarcoma, 16%). BCOR was expressed at low levels in 2 USC, 2 UEC/DDEC, and 2 UCS. PAX8 was generally positive but showed lower expression in UEC/DDEC (17/30, 57%) and in the sarcomatous portions of UCS (6/19, 32%). SATB2, cyclin D1, SALL4, and BCOR stain variable numbers of poorly-differentiated EC and must be carefully interpreted within morphologic and clinical context.

Disruption of the Gut Microbiota Confers Cisplatin Resistance in Epithelial Ovarian Cancer.

Epithelial ovarian cancer (EOC) is the leading cause of gynecologic cancer death. Despite initial responses to intervention, up to 80% of patient tumors recur and require additional treatment. Retrospective clinical analysis of patients with ovarian cancer indicates antibiotic use during chemotherapy treatment is associated with poor overall survival. Here, we assessed whether antibiotic (ABX) treatment would impact growth of EOC and sensitivity to cisplatin. Immunocompetent or immunocompromised mice were given untreated control or ABX-containing (metronidazole, ampicillin, vancomycin, and neomycin) water prior to intraperitoneal injection with EOC cells, and cisplatin therapy was administered biweekly until endpoint. Tumor-bearing ABX-treated mice exhibited accelerated tumor growth and resistance to cisplatin therapy compared with control treatment. ABX treatment led to reduced apoptosis, increased DNA damage repair, and enhanced angiogenesis in cisplatin-treated tumors, and tumors from ABX-treated mice contained a higher frequency of cisplatin-augmented cancer stem cells than control mice. Stool analysis indicated nonresistant gut microbial species were disrupted by ABX treatment. Cecal transplants of microbiota derived from control-treated mice was sufficient to ameliorate chemoresistance and prolong survival of ABX-treated mice, indicative of a gut-derived tumor suppressor. Metabolomics analyses identified circulating gut-derived metabolites that were altered by ABX treatment and restored by recolonization, providing candidate metabolites that mediate the cross-talk between the gut microbiome and ovarian cancer. Collectively, these findings indicate that an intact microbiome functions as a tumor suppressor in EOC, and perturbation of the gut microbiota with ABX treatment promotes tumor growth and suppresses cisplatin sensitivity. SIGNIFICANCE: Restoration of the gut microbiome, which is disrupted following antibiotic treatment, may help overcome platinum resistance in patients with epithelial ovarian cancer. See related commentary by Hawkins and Nephew, p. 4511.

Computational image features of immune architecture is associated with clinical benefit and survival in gynecological cancers across treatment modalities.

BACKGROUND: We present a computational approach (ArcTIL) for quantitative characterization of the architecture of tumor-infiltrating lymphocytes (TILs) and their interplay with cancer cells from digitized H&E-stained histology whole slide images and evaluate its prognostic role in three different gynecological cancer (GC) types and across three different treatment types (platinum, radiation and immunotherapy). METHODS: In this retrospective study, we included 926 patients with GC diagnosed with ovarian cancer (OC), cervical cancer, and endometrial cancer with available digitized diagnostic histology slides and survival outcome information. ArcTIL features quantifying architecture and spatial interplay between immune cells and the rest of nucleated cells (mostly comprised cancer cells) were extracted from the cell cluster graphs of nuclei within the tumor epithelial nests, surrounding stroma and invasive tumor front compartments on H&E-stained slides. A Cox proportional hazards model, incorporating ArcTIL features was fit on the OC training cohort (N=51), yielding an ArcTIL signature. A unique threshold learned from the training set stratified the patients into a low and high-risk group. RESULTS: The seven feature ArcTIL classifier was found to significantly correlate with overall survival in chemotherapy and radiotherapy-treated validation cohorts and progression-free survival in an immunotherapy-treated validation cohort. ArcTIL features relating to increased density of TILs in the epithelium and invasive tumor front were found to be associated with better survival outcomes when compared with those patients with an increased TIL density in the stroma. A statistically significant association was found between the ArcTIL signature and signaling pathways for blood vessel morphogenesis, vasculature development, regulation of cell differentiation, cell-substrate adhesion, biological adhesion, regulation of vasculature development, and angiogenesis. CONCLUSIONS: This study reveals that computationally-derived features from the spatial architecture of TILs and tumor cells are prognostic in GCs treated with chemotherapy, radiotherapy, and checkpoint blockade and are closely associated with central biological processes that impact tumor progression. These findings could aid in identifying therapy-refractory patients and further enable personalized treatment decision-making.

High TGF-ß signature predicts immunotherapy resistance in gynecologic cancer patients treated with immune checkpoint inhibition.

Various immune signatures predictive of resistance to immune checkpoint inhibitors (ICI) have been described in multiple solid cancers, but still under-investigated in gynecological (GYN) cancer. For 49 GYN cancer patients included in our study, without transcriptome signature, immune-related toxicity was the only clinical predictor of ICI treatment response (p = 0.008). The objective clinical response was the only predictor of progression-free survival (ICI-PFS, p = 0.0008) and overall survival (ICI-OS, p = 0.01). Commonly used ICI marker PD-L1 expression negatively correlated with progression-free survival (ICI-PFS) (p = 0.0019). We performed transcriptome and signaling pathway enrichment analyses based on ICI treatment responses and the survival outcome, and further estimated immune cell abundance using 547 gene markers. Our data revealed that TGF-ß regulated signaling pathway was noted to play an important role in immunotherapy failure. Using our 6-genes TGF-ß score, we observed longer ICI-PFS associated with lower TGF-ß score (8.1 vs. 2.8 months, p = 0.046), which was especially more prominent in ovarian cancer (ICI-PFS 16.6 vs. 2.65 months, p = 0.0012). Further, abundant immunosuppressive cells like T-regulatory cells, eosinophils, and M2 macrophages were associated with shorter ICI-OS and correlated positively with CD274 and CTLA4 expressions. This study provides insight on the potential role of TGF-ß in mediating immunotherapy resistance and cross-talking to immunosuppressive environment in GYN cancer. The TGF-ß score, if validated in a larger cohort, can identify patients who likely to fail ICI and benefit from targeting this pathway to enhance the response to ICI.

Case Report: Circulating Tumor DNA Fraction Analysis Using Ultra-Low-Pass Whole-Genome Sequencing Correlates Response to Chemoradiation and Recurrence in Stage IV Small-Cell Carcinoma of the Cervix - A Longitudinal Study.

Neuroendocrine carcinoma of the cervix is a rare and aggressive form of cervical cancer that presents with frequent metastasis at diagnosis and high recurrence rates. Primary treatment is multimodal, which often includes chemotherapy with or without radiation therapy. There are no data available to guide treatment for recurrence, and second-line therapies are extrapolated from small-cell lung carcinoma data. Close monitoring of these patients for recurrence is paramount. Evaluation of circulating tumor DNA (ctDNA) in the peripheral blood is an attractive approach due to its non-invasive nature. Ultra-low-pass whole-genome sequencing (ULP-WGS) can assess tumor burden and response to therapy and predict recurrence; however, data are lacking regarding the role of ULP-WGS in small-cell carcinoma of the cervix. This study demonstrates a patient whose response to chemotherapy and cancer recurrence was accurately monitored by ctDNA analysis using ULP-WGS and confirmed with radiologic imaging findings.

MDM2 amplification in malignant Brenner tumors may play a role in progression to malignancy and aid in separation from urothelial and other ovarian carcinomas.

Malignant Brenner tumor (MBT) is diagnosed in the setting of invasive high-grade carcinoma with urothelial-like morphology and the presence of an adjacent benign Brenner tumor (BBT) or borderline Brenner tumor (BLBT). MDM2 amplification was recently detected by next-generation sequencing on a small number of MBTs, potentially significant for future targeted therapy. Experience is limited, however, and evaluation of widely available MDM2 immunohistochemistry (IHC) has not been performed to determine clinical utility. After confirming all diagnoses morphologically and immunohistochemically, we performed MDM2 IHC on 4 MBTs, 3 BLBTs, 26 BBTs, 142 high-grade serous carcinomas (HGSC), 6 ovarian endometrioid carcinomas (OEC) with urothelial-like morphology, and 49 high-grade urothelial carcinomas (HGUC). MDM2 IHC was considered positive with diffuse (>25%) nuclear reactivity; in cases of patchy staining (10-25% nuclear reactivity), MDM2 was considered equivocal. Positive staining in <10% of cells was considered negative. In cases with positive or equivocal staining, MDM2 amplification was evaluated by fluorescence in-situ hybridization (FISH). Three MBTs (75%) showed diffuse nuclear reactivity for MDM2 by IHC, a finding corroborated by amplification of MDM2 in all three cases. One MBT and 2 BLBTs showed equivocal MDM2 IHC, but all three were negative for MDM2 amplification. The final BLBT, as well as all BBTs, HGSC, OEC, and HGUC, were negative for MDM2. In conclusion, our limited cohort confirms MDM2 amplification in MBT and suggests that MDM2 IHC may have an influence in rare diagnostically challenging cases.

Lenvatinib plus pembrolizumab in patients with advanced or recurrent uterine carcinosarcoma.

OBJECTIVES: To investigate the efficacy of pembrolizumab plus lenvatinib as a second-line or later-line therapy in women with advanced or recurrent uterine carcinosarcoma (UCS). METHODS: A single-institution pharmacy database was queried for women with advanced or recurrent UCS who were prescribed concurrent pembrolizumab and lenvatinib. Patient demographic, oncologic, and immunotherapy outcomes data were recorded. Univariate analysis summarized progression-free survival (PFS) and overall survival (OS). RESULTS: Seven patients with advanced or recurrent UCS were treated with combination pembrolizumab and lenvatinib, with a median age of 63.0 years. The majority had stage III or IV disease (n = 6, 85.7%) and had failed two or more lines of therapy (n = 7, 100.0%), and a minority were MMR deficient (n = 1, 14.3%) or PD-L1+ (n = 1, 14.3%). No partial or complete responses were observed. The median PFS was 2.6 months (95% CI, 0.9-11.2 months), and the median OS was 2.8 months (95% CI, 2.4-NE). CONCLUSIONS: In this small, retrospective series, we demonstrate that pembrolizumab and lenvatinib combination therapy may not be highly active in UCS and may be associated with similar PFS and OS as traditional cytotoxic regimens. Further study is warranted to assess the efficacy of this regimen in more targeted cohorts of women with advanced or recurrent UCS.

Immune cells and signatures characterize tumor microenvironment and predict outcome in ovarian and endometrial cancers.

Aims: We investigated immunogenomic signatures and correlated them with survival in ovarian cancer (OV) and endometrial cancer (EC). Materials & method: We used whole transcriptome sequencing data from uterine serous cancer and The Cancer Genome Atlas data of OV and EC (n = 719). Gene expression score was calculated. Population abundance of immune cells were estimated. Results: TGF-ß, myeloid cells, IFN-γ, T cells, B cells and endothelial cells predicted overall survival. Whereas CD47, neutrophils and endothelial cells predicted progression-free survival. In multivariate analyses, TGF-ß, CD47 and monocytic cells predicted survival in high levels of microsatellite instability (MSI-H) EC whereas high IFN-γ trended toward improved survival in the MSI-S EC. High IFN-γ/low TGF-ß and high IFN-γ/low CD47 signatures predicted longer overall survival. Low TGF-ß/low CD47 signature predicted longer overall survival only in the MSI-H EC. Conclusion: Our data support the role of immune markers in predicting survival in OV/EC.

Lay abstract We studied the association of immune markers and immune cells with survival outcome in ovarian and endometrial cancers. We performed gene expression analyses on tumor tissue of 719 patients. We generated signatures for the immune cells and markers and correlated them with survival outcome. We showed that specific immune cells and markers correlated strongly with survival even after we adjusted for other confounding factors. Further, we showed that these immune markers and immune cells have different correlation with survival when stratified in subtypes of endometrial cancer. Our data support the role of these immune markers in predicting survival outcome in ovarian and endometrial cancers.

Genomic analyses of high-grade neuroendocrine gynecological malignancies reveal a unique mutational landscape and therapeutic vulnerabilities.

High-grade neuroendocrine carcinoma of gynecologic origin (NEC-GYN) is a highly aggressive cancer that often affects young women. The clinical management of NEC-GYN is typically extrapolated from its counterpart, small cell carcinoma of the lung (SCLC), but, unfortunately, available therapies have limited benefit. In our NEC-GYN cohort, median progression-free survival (PFS) and overall survival (OS) were 1 and 12 months, respectively, indicating the highly lethal nature of this cancer. Our comprehensive genomic analyses unveiled that NEC-GYN harbors a higher mutational burden with distinct mutational landscapes from SCLC. We identified 14 cancer driver genes, including the most frequently altered KMT2C (100%), KNL1 (100%), NCOR2 (100%), and CCDC6 (93%) genes. Transcriptomic analysis identified several novel gene fusions; astonishingly, the MALAT1 lincRNA gene was found in ˜ 20% of all fusion events in NEC-GYN. Furthermore, NEC-GYN exhibited a highly immunosuppressive state, intact RB1 expression, and was uniquely enriched with the YAP1high molecular subtype. Our study identifies several potential therapeutic targets and suggests an urgent need to re-evaluate the treatment options for NEC-GYN.

Oncologic outcomes of endometrial cancer in patients with low-volume metastasis in the sentinel lymph nodes: An international multi-institutional study.

OBJECTIVE: To assess oncologic outcomes in endometrial cancer patients with low-volume metastasis (LVM) in the sentinel lymph nodes (SLNs). METHODS: Patients with endometrial cancer and SLN-LVM (≤2 mm) from December 3, 2009, to December 31, 2018, were retrospectively identified from 22 centers worldwide. Patients with International Federation of Gynecology and Obstetrics (FIGO) stage IV, adnexal involvement, or unknown adjuvant therapy (ATx) were excluded. RESULTS: Of 247 patients included, 132 had isolated tumor cell (ITC) and 115 had micrometastasis (MM). Overall 4-year recurrence-free survival (RFS) was 77.6% (95% CI, 70.2%-85.9%); median follow-up for patients without recurrence was 29.6 (interquartile range, 19.2-41.5) months. At multivariate analysis, Non-endometrioid (NE) (HR, 5.00; 95% CI, 2.50-9.99; P < .001), lymphovascular space invasion (LVSI) (HR, 3.26; 95% CI, 1.45-7.31; P = .004), and uterine serosal invasion (USI) (HR, 3.70; 95% CI, 1.44-9.54; P = .007) were independent predictors of recurrence. Among 47 endometrioid ITC patients without ATx, 4-year RFS was 82.6% (95% CI, 70.1%-97.2). Considering 18 ITC patients with endometrioid grade 1 disease, without LVSI, USI, or ATx, only 1 had recurrence (median follow-up, 24.8 months). CONCLUSIONS: In patients with SLN-LVM, NE, LVSI, and USI were independent risk factors for recurrence. Patients with any risk factor had poor prognosis, even when receiving ATx. Patients with ITC and grade 1 endometrioid disease (no LVSI/USI) had favorable prognosis, even without ATx. Further analysis (with more patients and longer follow-up) is needed to assess whether ATx can be withheld in this low-risk subgroup.

Review of 189 Consecutive Female Genital Skin and Mucosal Biopsies Submitted to an Academic Dermatopathology Practice.

OBJECTIVES: To describe consecutive vulvar biopsy cases and to create an educational template for pathology trainees and practicing pathologists. METHODS: We reviewed 189 consecutive biopsies from the female genital area skin and mucosa. We classified them based on etiologies and examined limited clinical information. RESULTS: We classified diagnoses as squamous intraepithelial neoplasia (21.5%), melanocytic neoplasia (17.9%), lichenoid dermatoses (15.9%), nonlichenoid dermatoses (11.3%), infectious (6.2%), reparative (4.6%), or miscellaneous (22.6%). The miscellaneous diagnoses included common entities (polyps and cysts) and rarer entities (calcinosis cutis, adnexal neoplasms, or basal cell carcinoma) and nonspecific descriptive diagnoses. Clinicians most often included the actual diagnosis in their differential for melanocytic lesions (83%) and least often for inflammatory lesions (32%). However, some cases included a clinical description without a differential diagnosis (14%) or no helpful clinical information (4%). The distribution of whether correct diagnoses were included in the clinical differential was similar between submitting physicians and midlevel providers. CONCLUSIONS: Understanding squamous and melanocytic pathology and the various lichenoid and other inflammatory diagnoses is critical for signing out female genital tract skin pathology. The cases examined in this report can serve as an educational template for trainees and practicing pathologists.

Molecularly Classified Uterine FIGO Grade 3 Endometrioid Carcinomas Show Distinctive Clinical Outcomes But Overlapping Morphologic Features.

FIGO grade 3 endometrioid endometrial carcinoma (EEC) is a heterogenous group of tumors with variable molecular and clinicopathologic characteristics but is treated clinically as a single entity. There is a need for additional objective markers to help guide management. The aim of this study was to evaluate a cohort of FIGO grade 3 EEC to validate the prognostic impact of molecular classification using POLE mutation (POLE-mut) analysis and immunohistochemistry for p53 and mismatch repair proteins. A secondary aim was to assess for any morphologic or immunophenotypic correlates among the molecular groups. Ninety-five cases of FIGO grade 3 EEC who underwent a hysterectomy at our institution were identified. Ten tumors (11%) harbored POLE-mut, 35 tumors (37%) showed mismatch repair deficiency, 18 tumors (19%) showed aberrant p53 staining (p53-ab), and 26 cases (27%) lacked all of these findings and were classified as no specific molecular profile. Six separate cases harbored >1 abnormality (multiple classifier), 5 of which had POLE-mut. The POLE-mut group and multiple classifier group showed excellent clinical outcomes, the p53-ab group showed the worst clinical outcomes and the 2 remaining groups showed intermediate prognosis. While the POLE-mut tumors showed a statistically significant enrichment for morphologic features including serous-like atypia and lymphocytic infiltrates, these findings were seen across all 4 molecular groups. There was no correlation between molecular grouping and tumor immunophenotypic findings, but overall 18% and 24% of tumors were completely negative for PAX-8 and estrogen receptor, respectively. Five CTNNB1 mutations were identified, 3 of which occurred in the context of a POLE-mut (including 1 multiple classifier case with MLH1/PMS2 loss). Thus our study corroborates the prognostic impact of molecular classification of high-grade endometrioid carcinoma of the uterus, achieved by readily available immunohistochemical stains in addition to POLE-mut analysis.

A Syngeneic Murine Model of Endometriosis using Naturally Cycling Mice.

Endometriosis is a leading cause of pelvic pain and infertility. It is defined by the presence of endometrial tissue in extrauterine locations. The development of novel therapies and diagnostic tools for endometriosis has been limited due in part to challenges in studying the disease. Outside of primates, few mammals menstruate, and none develop spontaneous endometriosis. Rodent models are popular but require artificial induction of endometriosis, with many utilizing either immunocompromised mice or surgically induced disease. Recently, more attention has been given to models involving intraperitoneal injection. We present a murine model of endometriosis that integrates several features of existing endometriosis models into a novel, simplified system that relies on microscopic quantification in lieu of subjective grading. In this model, we perform hormonal stimulation of donor mice, intraperitoneal injection, systematic abdominal survey and tissue harvest, and histologic quantification that can be performed and verified at any time after necropsy. This model requires minimal resources and training; does not require expertise by lab technicians in murine survival surgery or in the identification of gross endometriotic lesions; can be used in immunocompromised, immunocompetent, and/or mutant mice; and reliably creates endometriotic lesions that are histologically consistent with human endometriotic disease.

Predictors of response to immune checkpoint inhibition in a real world gynecologic cancer population.

Prognostic factors for immune checkpoint inhibitor (CPI) response in gynecologic cancer are limited. This retrospective study aimed to identify prognostic factors associated with improved overall response rate (ORR) and progression free survival (PFS) in gynecologic cancer patients receiving at least two cycles of CPI. PFS was compared by univariate cox regressions. Univariate and multivariable analyses were used for prognostic factors of PFS and ORR. 72 patients were identified (20 ovarian, 36 endometrial, 13 cervix, 1 vaginal, 2 others). Immune related adverse events (IRAE) occurred in 40.3% of patients (29/72). IRAE was associated with higher ORR (44.8% IRAE vs 20.9% no IRAE, OR 3.1, p = 0.024), improved PFS (12.9 m IRAE vs 4.7 m no IRAE, HR 0.43, p = 0.004) and improved OS (22.9 m IRAE vs 12.2 m no IRAE, HR 0.47, p = 0.021). Additionally, Clear cell histology had superior ORR compared to MSI stable endometrial and ovarian cancers (ORR 57.1% vs 11.8%, OR 10.0, p = 0.032). Responders more often had ARIDIA mutation, PI3K/PTEN alteration and less often had a P53 mutation. In a subset of six MSI-H, recurrent, chemo-naive endometrial cancer ORR was 83.3%. Overall, we found favorable outcomes after CPI for clear cell tumors and patients who developed IRAE. Additionally, first-line systemic therapy with CPI in recurrent MSI-H endometrial cancer had encouraging ORR with durable responses.

Uterine Mesenchymal Tumors: Hereditary Aspects.

The topic of hereditary gynecologic malignancies readily evokes associations between Lynch syndrome and endometrial adenocarcinoma, or between BRCA mutations and tubo-ovarian serous carcinoma, but other familial associations are less well-known. Two hereditary syndromes are known to be related to uterine mesenchymal tumors: hereditary leiomyomatosis and renal cell carcinoma syndrome and the tuberous sclerosis complex. In the following review, we describe the current literature on these syndromes, summarizing their clinical, morphologic, immunophenotypic, and genetic data. It is possible that the surgical pathologic diagnosis is the first indication of a familial syndrome, thus emphasizing the importance of a pathologist's familiarity with these potentially suggestive lesions.

Programmed Death Ligand 1 Expression Among 700 Consecutive Endometrial Cancers: Strong Association With Mismatch Repair Protein Deficiency.

OBJECTIVE: This study aims to determine the prevalence of programmed death ligand 1 (PD-L1) expression in endometrial carcinoma (EC) and determine clinical and pathological associations. METHODS: Immunohistochemistry for PD-L1 was performed on sections of a triple-core tissue microarray of 700 ECs. Positive PD-L1 expression, defined as 1% of cells staining positive, was evaluated in tumor and stromal compartments. Using age-adjusted logistic regression, we estimated odds ratios and 95% confidence intervals for associations between PD-L1 expression (overall and by staining compartment) with clinical and tumor characteristics. Kaplan-Meier plots and log-rank tests were used to evaluate associations between PD-L1 expression and EC-specific survival. RESULTS: PD-L1 expression was observed in 100 cases (14.3%), including 27 (3.9%) with expression in tumor cells only, 35 (5.0%) with expression in both tumor cells and stroma, and 38 (5.4%) with expression in stroma only. Expression was observed in ECs of different histologic types. Tumors characterized by loss of mismatch repair proteins were significantly associated with tumoral PD-L1 expression (P < 0.0001), but not with stromal PD-L1 expression. Both tumoral and stromal PD-L1 expressions were associated with high-grade endometrioid histology, nonendometrioid histology, and lymphovascular space invasion. We observed no significant associations between PD-L1 expression and EC-specific survival. CONCLUSIONS: PD-L1 is expressed in a significant proportion of EC and is associated with mismatch repair deficiency, potentially representing a mechanism of tumor immune evasion and a therapeutic target in EC.