Favorable Outcome of High-grade Endometrial Stromal Sarcoma in an Adolescent.

High-grade endometrial stromal sarcoma is a rare and aggressive soft tissue tumor characterized by YWHAE::NUTM2A/B translocations, diagnosis at a median of 50-60 years, and a poor prognosis (overall survival 30%-40%). We describe a 16-year-old patient with high-grade endometrial stromal sarcoma and regional nodal and pulmonary metastases who is a long-term survivor after grossly complete tumor resection, intensive chemotherapy, and pelvic radiotherapy. We discovered a previously undescribed YWHAE::NUTM2E translocation in the tumor. Our patient's favorable outcome suggests that intensive multimodality therapy with curative intent is appropriate for young patients with high-grade endometrial stromal sarcoma and highlights the importance of fertility preservation.

From morphology to methylome: epigenetic studies of Müllerian mesonephric-like adenocarcinoma reveal similarities to cervical mesonephric adenocarcinoma†.

Mesonephric adenocarcinomas (MAs) and mesonephric-like adenocarcinomas (MLAs) are rare, aggressive neoplasms that arise in the gynecologic tract and show overlapping morphologic, immunohistochemical, and molecular features. While MAs occur in the cervix and are thought to arise from mesonephric remnants, MLAs occur in the endometrium and ovary and are believed to originate from transdifferentiation of Müllerian lesions. Both MAs and MLAs show a variety of architectural patterns, exhibit frequent expression of GATA3 by immunohistochemistry, and harbor KRAS mutations. In a recent article published in The Journal of Pathology, Kommoss and colleagues used DNA methylation profiling to extend these similarities and showed that MLAs and MAs cluster together based on their epigenetic signatures and are epigenetically distinct from other Müllerian adenocarcinomas. They also showed that MLAs and MAs harbor a high number of global copy number alterations. This study provides evidence that MLAs more closely resemble MAs than Müllerian carcinomas on an epigenetic level. As a result, the authors argue that MLA should be renamed 'mesonephric-type adenocarcinoma.' Further research is needed to establish the relationship between these two entities, their etiology, and pathogenesis. © 2024 The Pathological Society of Great Britain and Ireland.

Endometrioid Endometrial RNA Index Predicts Recurrence in Stage I Patients.

PURPOSE: Risk prediction with genomic and transcriptomic data has the potential to improve patient outcomes by enabling clinicians to identify patients requiring adjuvant treatment approaches, while sparing low-risk patients from unnecessary interventions. Endometrioid endometrial carcinoma (EEC) is the most common cancer in women in developed countries, and rates of endometrial cancer are increasing. EXPERIMENTAL DESIGN: We collected a 105-patient case-control cohort of stage I EEC comprised of 45 patients who experienced recurrence less than 6 years after excision, and 60 FIGO grade matched controls without recurrence. We first utilized two RNA based, previously validated machine learning approaches, namely EcoTyper and Complexity Index in Sarcoma (CINSARC). We developed Endometrioid Endometrial RNA Index (EERI) which uses RNA expression data from 46 genes to generate a personalized risk score for each patient. EERI was trained on our 105-patient cohort and tested on a publicly available cohort of 263 stage I EEC patients. RESULTS: EERI was able to predict recurrences with 94% accuracy in the training set and 81% accuracy in the test set. In the test set, patients assigned as EERI high-risk were significantly more likely to experience recurrence (30%) than the EERI low-risk group (1%) with a hazard ratio of 9.9 (95% CI 4.1-23.8, P <0.001). CONCLUSIONS: Tumors with high-risk genetic features may require additional treatment or closer monitoring and are not readily identified using traditional clinicopathologic and molecular features. EERI performs with high sensitivity and modest specificity, which may benefit from further optimization and validation in larger independent cohorts.

Scattering-Based Light-Sheet Microscopy Imaging of Human Papillomavirus-Associated Squamous Lesions of the Anal Canal: A Proof-of-Principle Study.

Demand for anal cancer screening is expected to rise following the recent publication of the Anal Cancer-HSIL Outcomes Research trial, which showed that treatment of high-grade squamous intraepithelial lesions significantly reduces the rate of progression to anal cancer. While screening for human papillomavirus-associated squamous lesions in the cervix is well established and effective, this is less true for other sites in the lower anogenital tract. Current anal cancer screening and prevention rely on high-resolution anoscopy with biopsies. This procedure has a steep learning curve for providers and may cause patient discomfort. Scattering-based light-sheet microscopy (sLSM) is a novel imaging modality with the potential to mitigate these challenges through real-time, microscopic visualization of disease-susceptible tissue. Here, we report a proof-of-principle study that establishes feasibility of dysplasia detection using an sLSM device. We imaged 110 anal biopsy specimens collected prospectively at our institution's dysplasia clinic (including 30 nondysplastic, 40 low-grade squamous intraepithelial lesion, and 40 high-grade squamous intraepithelial lesion specimens) and found that these optical images are highly interpretable and accurately recapitulate histopathologic features traditionally used for the diagnosis of human papillomavirus-associated squamous dysplasia. A reader study to assess diagnostic accuracy suggests that sLSM images are noninferior to hematoxylin and eosin images for the detection of anal dysplasia (sLSM accuracy = 0.87; hematoxylin and eosin accuracy = 0.80; P = .066). Given these results, we believe that sLSM technology holds great potential to enhance the efficacy of anal cancer screening by allowing accurate sampling of diagnostic tissue at the time of anoscopy. While the current imaging study was performed on ex vivo biopsy specimens, we are currently developing a handheld device for in vivo imaging that will provide immediate microscopic guidance to high-resolution anoscopy providers.

Vulvar Cancer, Version 3.2024, NCCN Clinical Practice Guidelines in Oncology.

Vulvar cancer is annually diagnosed in an estimated 6,470 individuals and the vast majority are histologically squamous cell carcinomas. Vulvar cancer accounts for 5% to 8% of gynecologic malignancies. Known risk factors for vulvar cancer include increasing age, infection with human papillomavirus, cigarette smoking, inflammatory conditions affecting the vulva, and immunodeficiency. Most vulvar neoplasias are diagnosed at early stages. Rarer histologies exist and include melanoma, extramammary Paget's disease, Bartholin gland adenocarcinoma, verrucous carcinoma, basal cell carcinoma, and sarcoma. This manuscript discusses recommendations outlined in the NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for treatments, surveillance, systemic therapy options, and gynecologic survivorship.

The Malignant Potential of Ovarian Steroid Cell Tumors Revisited: A Multi-institutional Clinicopathologic Analysis of 115 Cases.

Steroid cell tumors (SCTs) of the ovary are rare and understudied, and as such, uncertainties remain about their malignant potential, as well as clinicopathologic predictors of patient outcome. Based on a multi-institutional cohort of cases, we present findings from the largest study of SCT reported to date. Clinicopathologic data were documented on 115 cases of SCT that were assembled from 17 institutions. The median patient age was 55 years (range: 9 to 84). When measured, preoperative androgen levels were elevated in 84.2% (48/57) of patients. A total of 111 (96.5%) cases were classified as stage I (103 stage IA; 2 stage IB; 6 stage IC). The stage distribution for the remaining 4 patients was as follows: stage II (n = 1), III (n = 3; 1 IIIA, 1 IIIB, 1 IIIC). The median tumor size was 3 cm (range: 0.2 to 22). Cytologic atypia, microscopic tumor necrosis, microscopic tumor hemorrhage, and a mitotic index of >1 mitotic figure/10 high-power fields were present in 52% (60/115), 9.6% (11/115), 37% (43/115), and 19% (22/115) of cases, respectively. Of 115 patients, 7 (6.1%) recurred postexcision, 4 (3.5%) ultimately died of disease, and 10 (8.7%) either recurred, died of disease, or were advanced stage at presentation. The median duration to recurrence postresection was 33 months (range: 23 to 180). Four of the 7 recurrences were stage IA at baseline. Tumor size >4 cm, International Federation of Gynecology and Obstetrics (FIGO) stage ≥IB, tumor necrosis, and tumor hemorrhage were each significantly associated with reduced recurrence-free survival in log-rank tests and univariable Cox models, with age older than 65 years being of marginal significance (hazard ratio [HR]: 5.4, 95% CI: 1.0-30.0, P = 0.05). Multivariable analyses suggested that FIGO stage ≥IB (HR: 27.5, 95% CI: 2.6-290.5), and age older than >65 years (HR: 21.8, 95% CI: 1.6-303.9) were the only parameters that were independently associated with recurrence. Cross-section analyses showed that tumor necrosis, tumor hemorrhage, and larger tumor size were significantly associated with a FIGO stage ≥IB status, which bolstered the conclusion that they are not independent predictors of recurrence. In summary, <10% of SCTs are clinically malignant, a substantially lower frequency than has previously been reported in the literature. Clinicopathologic predictors of patient outcomes that are prospectively applicable in practice could not be definitively established. Recurrences may occur many years (up to 15 y in this study) after primary resection, even in stage IA cases.

UCHL1 is a potential molecular indicator and therapeutic target for neuroendocrine carcinomas.

Neuroendocrine carcinomas, such as neuroendocrine prostate cancer and small-cell lung cancer, commonly have a poor prognosis and limited therapeutic options. We report that ubiquitin carboxy-terminal hydrolase L1 (UCHL1), a deubiquitinating enzyme, is elevated in tissues and plasma from patients with neuroendocrine carcinomas. Loss of UCHL1 decreases tumor growth and inhibits metastasis of these malignancies. UCHL1 maintains neuroendocrine differentiation and promotes cancer progression by regulating nucleoporin, POM121, and p53. UCHL1 binds, deubiquitinates, and stabilizes POM121 to regulate POM121-associated nuclear transport of E2F1 and c-MYC. Treatment with the UCHL1 inhibitor LDN-57444 slows tumor growth and metastasis across neuroendocrine carcinomas. The combination of UCHL1 inhibitors with cisplatin, the standard of care used for neuroendocrine carcinomas, significantly delays tumor growth in pre-clinical settings. Our study reveals mechanisms of UCHL1 function in regulating the progression of neuroendocrine carcinomas and identifies UCHL1 as a therapeutic target and potential molecular indicator for diagnosing and monitoring treatment responses in these malignancies.

Specific Pathology Features Enrich Selection of Endometrial Carcinomas for POLE Testing.

Identification of ultramutated/ POLE -mutated endometrial carcinomas ( POLEM ECs) has important implications given its association with better prognosis. However, POLE mutation testing is not widely available. Our objective was to evaluate POLEM ECs versus POLE wild-type ( POLEWT ) ECs, within a cohort of consultation cases with features suggestive of an ultramutated phenotype. Consultation cases of EC that had undergone POLE hotspot mutation testing over a 3.5-year period were included. Tumor morphology and immunohistochemistry were reviewed for both groups. Chi-square test and t test were used for statistical analysis. Of 25 consultation cases, 12 harbored a POLE mutation (48%) and 13 were wild-type (52%). Patients with POLEM ECs were younger (59 vs. 71.3 y; P =0.01). Ambiguous histomorphology (5/12 vs. 1/13; P =0.04) and the presence of more than rare bizarre nuclei (8/12 vs. 2/12; P =0.01) differed significantly between POLEM and POLEWT ECs, respectively. In the POLEM group, one case (1/12) demonstrated PMS2 loss, and one (1/12) showed subclonal MLH1/PMS2 loss. Among POLEWT ECs, 3/13 (23%) showed MLH1/PMS2 loss. p53 was subclonally overexpressed in 4/10 POLEM and 1/13 POLEWT cases ( P =0.06). Mutant p53 patterns were seen in 1/10 POLEM versus 6/13 of POLEWT ECs, respectively ( P =0.06). Within our cohort, the specificity of ambiguous histomorphology, bizarre nuclei, subclonal biomarker expression, and marked tumor-infiltrating lymphocytes for POLEM EC was 83%, 80%, 80%, and 71%, respectively. Where universal POLE testing is not available, these data suggest that morphologic screening (particularly ambiguous histomorphology and the presence of more than rare bizarre nuclei) can be useful for selective enrichment of ECs for POLE testing.

Clinical Features of SARS-CoV-2 Infection During Pregnancy and Associated Placental Pathologies.

SUMMARY: We reviewed the clinicopathologic findings of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-exposed placentas at our institution. We identified patients diagnosed with SARS-CoV-2 during pregnancy (March-October 2020). Clinical data included gestational age at diagnosis and delivery and maternal symptoms. Hematoxylin and eosin slides were reviewed for maternal vascular malperfusion, fetal vascular malperfusion, chronic villitis, amniotic fluid infection, intervillous thrombi, fibrin deposition, and infarction. Immunohistochemistry (IHC) for coronavirus spike protein and RNA in situ hybridization (ISH) for SARS-CoV-2 was performed on a subset of blocks. A review of placentas from age-matched patients received March-October 2019 was conducted as a comparison cohort. A total of 151 patients were identified. Placentas in the 2 groups were similar in weight for gestational age and had similar rates of maternal vascular malperfusion, fetal vascular malperfusion, amniotic fluid infection, intervillous thrombi, fibrin deposition, and infarction. Chronic villitis was the only significantly different pathologic finding between cases and controls (29% of cases showed chronic villitis vs. 8% of controls, P <0.001). Overall, 146/151 (96.7%) cases were negative for IHC and 129/133 (97%) cases were negative for RNA ISH. There were 4 cases that stained positively for IHC/ISH, 2 of which showed massive perivillous fibrin deposition, inflammation, and decidual arteriopathy. Coronavirus disease 2019 (COVID-19)-positive patients were more likely to self-identify as Hispanic and more likely to have public health insurance. Our data suggests SARS-CoV-2 exposed placentas that stain positively for SARS-CoV-2 show abnormal fibrin deposition, inflammatory changes, and decidual arteriopathy. The group of patients with clinical COVID-19 are more likely to show chronic villitis. IHC and ISH evidence of viral infection is rare.

NCCN Guidelines® Insights: Cervical Cancer, Version 1.2024.

The NCCN Guidelines for Cervical Cancer provide recommendations for all aspects of management for cervical cancer, including the diagnostic workup, staging, pathology, and treatment. The guidelines also include details on histopathologic classification of cervical cancer regarding diagnostic features, molecular profiles, and clinical outcomes. The treatment landscape of advanced cervical cancer is evolving constantly. These NCCN Guidelines Insights provide a summary of recent updates regarding the systemic therapy recommendations for recurrent or metastatic disease.

Aberrant nuclear ß-catenin distribution does not prognosticate recurrences of endometrioid endometrial cancers - A retrospective single-institutional study.

OBJECTIVE: Aberrant ß-catenin distribution has been theorized as a predictive biomarker for recurrence in early stage, low grade endometrioid endometrial cancer. METHODS: This retrospective single-institution cohort study reviewed 410 patients with endometrial cancer from May 2018 to May 2022. Only endometrioid histology was included. Demographic and clinicopathological data were collected from the medical records. Univariate and multivariate logistic regressions, and sensitivity analyses for early stage, low grade and no specific molecular profile (NSMP) tumors were performed. RESULTS: 297 patients were included for analysis. Most patients were over 60 years old, White, and with a BMI >30 and early stage low grade disease. Aberrant ß-catenin distribution was found in 135 patients (45.5%) and wild type membranous ß-catenin distribution in 162 (54.5%). While TP53 mutation correlated with endometrial cancer recurrence in this cohort (OR = 4.78), aberrant ß-catenin distribution did not correlate in the overall population (OR = 0.75), the early stage low grade cancers (OR = 0.84), or the NSMP group (OR = 1.41) on univariate or multivariate analysis. No correlation between ß-catenin distribution and local (OR = 0.61) or distant recurrences (OR = 0.90) was detected. CONCLUSIONS: Aberrant ß-catenin distribution did not significantly correlate with recurrence in endometrioid endometrial cancer, nor in the early stage, low grade and NSMP sub-cohorts.

SMARCA4 loss irrelevant for ARID1A mutated ovarian clear cell carcinoma: A case report.

Clear cell carcinomas are rare and relatively chemo-insensitive ovarian cancers with a characteristic molecular pathogenesis. Alterations in ARID1A, a component of the multiprotein chromatin remodeling complex SWI/SNF, are likely early events in the development of ovarian clear cancers arising from atypical endometriosis. Insight into additional driver events and particularly mutations in the same chromatin remodeling complex is limited. Isolated loss of SMARCA4, encoding the ATPase of the SWI/SNF complex, characterizes other aggressive gynecologic cancers including small cell carcinomas of the ovary hypercalcemic type (SCCOHT), undifferentiated endometrial carcinomas (UDEC), and uterine sarcomas (SDUS). The ovarian clear cell carcinoma of a 48-year-old showed in the initial surgical specimen a subclonal loss of SMARCA4 in addition to an ARID1A mutation, i.e., two alterations in the SWI/SNF heterochromatin remodeling complex. We anticipated that the SMARCA4 loss would worsen the disease course in analogy to SCCOHT, UDEC, and SDUS. However, the disease did not accelerate. Instead, the recurrent disease showed restored SMARCA4 expression while retaining the ARID1A mutation. Combinatorial redundancy, diversity and sequence in the SWI/SNF complex assembly as well as DNA- and tissue-specificity may explain the observed irrelevance of SMARCA4 loss in the presented ARID1A mutated ovarian clear cell carcinoma.

FIGO 2023 endometrial cancer staging: too much, too soon?

An updated International Federation of Gynecology and Obstetrics (FIGO) staging system for endometrial carcinoma was introduced in June 2023. The new system represents a significant departure from traditional endometrial and other gynecological carcinoma staging systems which are agnostic of parameters such as tumor type, tumor grade, lymphovascular space invasion, and molecular alterations. The updated system, which incorporates all of these 'non-anatomical' parameters, is an attempt to make staging more personalized and relevant to patient prognostication and management, and to align with the European Society of Gynaecological Oncology/European Society for Radiotherapy and Oncology/European Society of Pathology (ESGO/ESTRO/ESP) risk stratification. Herein, we present a critical review of the new staging system and discuss its advantages and disadvantages. The authors propose that the new FIGO staging system should be first appraised at a multi-institutional and global level with the input of all relevant societies (gynecology, pathology, gynecologic oncology, medical oncology, radiation oncology) to understand the impact, scope, and supporting evidence of the proposed changes. Such a process is fundamental to produce a robust system that pathologists and treating clinicians can adopt.

Clinical Behavior and Molecular Landscape of Stage I p53-Abnormal Low-Grade Endometrioid Endometrial Carcinomas.

PURPOSE: The clinical significance of the p53-abnormal (p53abn) molecular subtype in stage I low-grade endometrioid endometrial carcinoma (EEC) is debated. We aimed to review pathologic and molecular characteristics, and outcomes of stage I low-grade p53abn EEC in a large international cohort. EXPERIMENTAL DESIGN: Previously diagnosed stage I p53abn EC (POLE-wild-type, mismatch repair-proficient) low-grade EEC from Canadian retrospective cohorts and PORTEC-1&2 trials were included. Pathology review was performed by six expert gynecologic pathologists blinded to p53 status. IHC profiling, next-generation sequencing, and shallow whole-genome sequencing was performed. Kaplan-Meier method was used for survival analysis. RESULTS: We identified 55 stage I p53abn low-grade EEC among 3,387 cases (2.5%). On pathology review, 17 cases (31%) were not diagnosed as low-grade EEC by any pathologists, whereas 26 cases (47%) were diagnosed as low-grade EEC by at least three pathologists. The IHC and molecular profile of the latter cases were consistent with low-grade EEC morphology (ER/PR positivity, patchy p16 expression, PIK3CA and PTEN mutations) but they also showed features of p53abn EC (TP53 mutations, many copy-number alterations). These cases had a clinically relevant risk of disease recurrence (5-year recurrence-free survival 77%), with pelvic and/or distant recurrences observed in 12% of the patients. CONCLUSIONS: A subset of p53abn EC is morphologically low-grade EEC and exhibit genomic instability. Even for stage I disease, p53abn low-grade EEC are at substantial risk of disease recurrence. These findings highlight the clinical relevance of universal p53-testing, even in low-grade EEC, to identify women at increased risk of recurrence.

Does lymph node assessment change the prognostic significance of substantial LVSI and p53 status in endometrial endometrioid carcinoma?

OBJECTIVE: The PORTEC-2 update suggested that substantial lymphovascular space invasion (LVSI) and abnormal p53 expression (p53abnl) predict for poorer outcomes and that these patients should be treated with external beam radiation therapy (EBRT). We aim to determine if patients with these risk factors who undergo a lymph node (LN) assessment show similar outcomes. METHODS: We retrospectively reviewed 126 patients with FIGO 2009 stage IA grade 3, stage IB grade 1-2, and stage IIIC (positive LN but no other stage II/III risk factors) endometrioid endometrial cancer who underwent LN assessment. Local (LR), regional recurrences (RR), and distant metastases were analyzed using competing risk methods, and overall survival (OS) was analyzed using Kaplan-Meier. RESULTS: Median follow-up time was 37.2 months. OS was significantly different between patients with and without p53abnl expression (16.7% versus 3.1% deceased), and between patients with and without LVSI (11.1% versus 1.5% deceased; p < 0.01 for both). The 2-year cumulative incidence of LR for patients with p53abnl versus wild type p53 and LVSI versus no LVSI was 11.1% (95% CI 0-25.6) versus 2.2% (95% CI 0-5.25; p = 0.04), and 11.4% (95% CI 2.0-20.9) versus 0%, respectively (p < 0.01). The 2-year cumulative RR in patients with LVSI versus no LVSI was 6.9% (95% CI 0-14.4) versus 0% (p = 0.05). No patients who completed pelvic RT experienced an in-field recurrence. CONCLUSIONS: Despite LN assessment, patients with high-intermediate risk early-stage or stage IIIC (with positive lymph nodes only but no other stage II or III risk factors) endometrial cancer with p53abnl expression and/or LVSI have worse outcomes. These patients may derive benefit from intensification with EBRT to improve local and pelvic control.

Detection of FOXL2 C134W Mutation Status by a Novel BaseScope In Situ Hybridization Assay is Highly Sensitive and Specific for Adult Granulosa Cell Tumors.

Adult granulosa cell tumors (AGCTs) are a molecularly distinct group of malignant ovarian sex cord-stromal tumors (SCSTs) characterized by a nearly ubiquitous c.402C>G/p.C134W mutation in FOXL2 (hereafter referred to as "C134W"). In some cases, AGCT exhibits marked morphologic overlap with other SCSTs and has an identical immunophenotype, and molecular testing may be necessary to help confirm the diagnosis. However, molecular testing is time consuming, relatively expensive, and unavailable in many pathology laboratories. We describe the development and validation of an in situ hybridization (ISH) custom BaseScope assay for the detection of the FOXL2 C134W mutation. We evaluated 106 ovarian SCSTs, including 78 AGCTs, 9 juvenile granulosa cell tumors, 18 fibromas (cellular and conventional), and 1 SCST, not otherwise specified, as well as 53 epithelial ovarian tumors (42 endometrioid carcinomas and 11 carcinosarcomas) and 1 STK11 adnexal tumor for the presence or absence of FOXL2 wild-type and FOXL2 C134W RNA expression via BaseScope-ISH. Fifty-one tumors had previously undergone DNA sequencing of the FOXL2 gene. Across the entire cohort, the FOXL2 C134W probe staining was positive in 77 of 78 (98.7%) AGCTs. Two of 81 (2.5%) non-AGCTs also showed positive staining, both of which were epithelial ovarian tumors. The assay worked in tissue from blocks >20 years old. There was 100% concordance between the FOXL2 sequencing and BaseScope-ISH results. Overall, assessment of FOXL2 mutation status by custom BaseScope-ISH demonstrated 98.7% sensitivity and 97.5% specificity for the diagnosis of AGCT. BaseScope-ISH for FOXL2 C134W represents a reasonable alternative to sequencing, is quicker and less expensive, and is more easily incorporated than molecular testing into many pathology laboratories. It also has the advantage of requiring less tissue, and the neoplastic cells can be directly visualized on stained sections.

Adjuvant radiation therapy in early-stage endometrial cancer with abnormal beta-catenin expression is associated with improved local control.

OBJECTIVES: Emerging data suggests that abnormal (nuclear) ß-catenin expression in some settings is associated with poorer outcomes. Our study aimed to verify the significance of abnormal ß-catenin expression in early-stage endometrial cancer patients and determine if adjuvant radiation therapy (RT) improves local control. METHODS: We identified 213 patients with FIGO 2018 stage I-II endometrioid endometrial cancer who underwent surgery from 2009 to 2021 with ß-catenin expression assessed. Vaginal, regional, and distant recurrences were analyzed using competing risk methods, and overall survival was analyzed using Kaplan-Meier. RESULTS: Median follow up was 53.2 months; 6.9% experienced vaginal, 8.2% regional, and 7.4% distant recurrence. For the entire cohort, abnormal ß-catenin expression was significantly associated with vaginal recurrence and remained significant on multivariate analysis (p = 0.03). There were 114 patients in the no specific molecular profile (NSMP) subgroup, and abnormal ß-catenin expression was present in 46.5%. In the NSMP subgroup, abnormal ß-catenin expression was associated with increased rates of vaginal recurrence (p = 0.06). Abnormal ß-catenin expression in the NSMP subgroup was significant on multivariate analysis for vaginal recurrence (p = 0.04). RT significantly decreased vaginal recurrences in the entire cohort in patients with abnormal ß-catenin expression (0%) versus wild type expression (17.5%; p = 0.03). In the NSMP subgroup 0% of patients who received RT versus 20.9% of patients who did not receive RT experienced a vaginal recurrence (p = 0.03). CONCLUSION: Use of adjuvant RT for stage I-II NSMP endometrial cancer with abnormal ß-catenin expression improved local control. RT should be considered in these patients to decrease risk of vaginal recurrences.

Molecular correlates of invasion pattern in HPV-associated endocervical adenocarcinoma: emergence of two distinct risk-stratified tiers.

BACKGROUND: The pattern-based (Silva) classification of invasive human papilloma virus (HPV)-associated endocervical adenocarcinomas (HPVA) is an established and reproducible method to predict outcomes for this otherwise stage-dependent group of tumours. Previous studies utilising targeted sequencing have shown a correlation between mutational profiles and an invasive pattern. However, such correlation has not been explored using comprehensive molecular testing. DESIGN: Clinicopathologic data including invasive pattern (Silva groups A, B, and C) was collected for a cohort of invasive HPVA, which previously underwent massive parallel sequencing using a panel covering 447 genes. Pathogenic alterations, molecular signatures, tumour mutational burden (TMB), and copy number alterations (CNA) were correlated with pattern of invasion. RESULTS: Forty five HPVA (11 pattern A, 17 pattern B, and 17 pattern C tumours) were included. Patients with pattern A presented at stage I with no involved lymph nodes or evidence of recurrence (in those with >2 months of follow-up). Patterns B and C patients also mostly presented at stage I with negative lymph nodes, but had a greater frequency of recurrence; 3/17 pattern B and 1/17 pattern C HPVAs harboured lymphovascular space invasion (LVI). An APOBEC mutational signature was detected only in Silva pattern C tumours (5/17), and pathogenic PIK3CA changes were detected only in destructively invasive HPVA (patterns B and C). When cases were grouped as low-risk (pattern A and pattern B without LVI) and high-risk (pattern B with LVI and pattern C), high-risk tumours were enriched in mutations in PIK3CA, ATRX, and ERBB2. There was a statistically significant difference in TMB between low-risk and high-risk pattern tumours (P = 0.006), as well as between Pattern C tumours with and without an APOBEC signature (P = 0.002). CNA burden increased from pattern A to C. CONCLUSION: Our findings further indicate that key molecular events in HPVA correlate with the morphologic invasive properties of the tumour and their aggressiveness. Pattern B tumours with LVI clustered with pattern C tumours, whereas pattern B tumours without LVI approached pattern A genotypically. Our study provides a biologic foundation for consolidating the Silva system into low-risk (pattern A + B without LVI) and high-risk (pattern B with LVI and pattern C) categories.

High-Grade Endometrial Stromal Sarcomas With YWHAE::NUTM2 Gene Fusion Exhibit Recurrent CDKN2A Alterations and Absence of p16 Staining is a Poor Prognostic Marker.

High-grade endometrial stromal sarcomas (HGESSs) are aggressive uterine tumors harboring oncogenic fusion proteins. We performed a molecular study of 36 HGESSs with YWHAE::NUTM2 gene fusion, assessing co-occurring genetic events, and showed that these tumors frequently harbor recurrent events involving the CDKN2A locus on chromosome 9p. Using array-based copy number profiling and CDKN2A fluorescence in situ hybridization, we identified homozygous and hemizygous deletions of CDKN2A in 18% and 14% of tumors (n = 22 analyzed), respectively. While all YWHAE-rearranged HGESSs with retained disomy for CDKN2A were immunohistochemically positive for p16INK4 (p16), all tumors with homozygous deletion of CDKN2A showed complete absence of p16 staining. Of the 2 tumors with a hemizygous deletion of CDKN2A, 1 showed diffuse and strong p16 positivity, whereas the other showed complete absence of staining. In the p16-negative case, we did not find intragenic mutations or DNA promoter methylation to explain the p16 protein loss, implicating other mechanisms in the regulation of protein expression. In our cohort, subclonal or complete absence of p16 staining was associated with worse overall survival compared with positive p16 staining (1-year overall survival: 28.6% vs 90.7%, respectively; n = 32; P < .001), with all 7 patients in the p16-negative group having succumbed to their disease within 2 years of diagnosis. Our results suggested CDKN2A alterations as a cooperative driver of tumorigenesis in a subset of HGESSs with the YWHAE::NUTM2 gene fusion and showed p16 to be a potential prognostic marker.