Jessica N McAlpine

Prognostic values of molecular subtypes and SWI/SNF protein expression in de‐differentiated/undifferentiated endometrial carcinoma

AimsClassification and risk stratification of endometrial carcinoma (EC) has transitioned from histopathological features to molecular classification, e.g. the ProMisE classifier, identifying four prognostic subtypes: POLE mutant (POLEmut) with almost no recurrence or disease‐specific death events, mismatch repair deficient (MMRd) and no specific molecular profile (NSMP), with intermediate outcome and p53 abnormal (p53abn) with poor outcomes. However, the applicability of molecular classification is unclear in rare but aggressive histotypes of EC, e.g. de‐differentiated and undifferentiated endometrial cancers (DD/UDEC). Here, we aim to assembled a cohort of DD/UDEC from a single institution and analysed the prognostic significance of ProMisE molecular subtypes and the expression of SWItch/sucrose non‐fermentable (SWI/SNF) chromatin remodelling complex members, previously implicated in the pathogenesis of DD/UDEC.Methods and resultsWe accrued 88 DD/UDEC cases, assessed POLE status by Sanger sequencing and performed immunohistochemistry for p53, mismatch repair and SWI/SNF proteins on the tissue microarrays assembled. Assignment of molecular subtypes was possible in 80 tumours; POLE sequencing failed in the remaining eight cases. There were 12 (15%) POLEmut, 44 (55%) MMRd, 14 (17.5%) p53abn and 10 (12.5%) NSMP DD/UDEC. POLEmut DD/UDECs had excellent outcomes, but the other three molecular subtypes all had poor outcomes, with no significant differences among them. The loss of one or more SWI/SNF proteins [AT‐rich interactive domain‐containing protein 1A (ARID1A), ARID1B, SWI/SNF‐related, matrix‐associated, actin‐dependent regulator of chromatin, subfamily A, member 4 (SMARCA4), SMARCA2], observed in 66% (55 of 83) cases, was not of prognostic significance.ConclusionsThese results indicate that all molecular subtypes of DD/UDEC except POLEmut behave in an aggressive fashion. Further study is needed to determine whether these molecular alterations can be targeted with adjuvant therapy, in order to improve outcomes of patients with DD/UDEC.

Recurrence rates and patterns of recurrence in stage IA p53abn endometrial cancer with and without myometrial invasion

Optimal management of patients with stage IA p53abn endometrial cancer without myoinvasion, classified as intermediate risk in the 2020 European Society of Gynaecological Oncology, European Society for Radiotherapy and Oncology, and European Society of Pathology (ESGO-ESTRO-ESP) guidelines, and the 2022 European Society of Medical Oncology (ESMO) guidelines, is currently unclear. Practice varies from surgery alone to adjuvant radiation±chemotherapy. Our aim was to assess the risk of disease recurrence in patients with stage IA p53abn endometrial cancer without myoinvasion compared with stage IA with myoinvasion (<50%). Stage IA p53abn endometrial cancers were identified from retrospective cohorts. Cases were segregated into stage IA with no myoinvasion, including (1) tumor restricted to a polyp, (2) residual endometrial tumor, and (3) no residual tumor in hysterectomy specimen, versus stage IA p53abn with myoinvasion (<50%), with treatment and outcomes assessed. There were 65 stage IA p53abn endometrial cancers with no myoinvasion (22 polyp confined, 38 residual endometrial tumor, 2 no residual in hysterectomy specimen, 3 not specified) and 97 with myoinvasion. There was no difference in survival outcomes in patients with stage IA without myoinvasion (16% of patients recurred, 19% if there was residual endometrial disease) compared with stage IA with myoinvasion (17%). The risk of recurrence was lowest in patients with stage IA p53abn endometrial cancer without myoinvasion treated with chemotherapy±radiation (8%). Most recurrences in patients with stage IA without myoinvasion were distant (89%), with no isolated vaginal vault recurrences, and all except one distant recurrence occurred in patients who had not received adjuvant chemotherapy. The recurrence rate in patients with stage IA p53abn endometrial cancer without myoinvasion was 16%, highest in the setting of residual endometrial disease (19%), and exceeding the threshold where adjuvant therapy is often considered. The high frequency of distant recurrences observed may support chemotherapy as part of the treatment regimen.

Targeted and Shallow Whole-Genome Sequencing Identifies Therapeutic Opportunities in p53abn Endometrial Cancers

Abstract Purpose: Shallow whole-genome sequencing (sWGS) can detect copy-number (CN) aberrations. In high-grade serous ovarian cancer (HGSOC) sWGS identified CN signatures such as homologous recombination deficiency (HRD) to direct therapy. We applied sWGS with targeted sequencing to p53abn endometrial cancers to identify additional prognostic stratification and therapeutic opportunities. Experimental Design: sWGS and targeted panel sequencing was performed on formalin-fixed, paraffin-embedded p53abn endometrial cancers. CN alterations, mutational data and CN signatures were derived, and associations to clinicopathologic and outcomes data were assessed. Results: In 187 p53abn endometrial cancers, 5 distinct CN signatures were identified. Signature 5 was associated with BRCA1/2 CN loss with features similar to HGSOC HRD signature. Twenty-two percent of potential HRD cases were identified, 35 patients with signature 5, and 8 patients with BRCA1/2 somatic mutations. Signatures 3 and 4 were associated with a high ploidy state, and CCNE1, ERBB2, and MYC amplifications, with mutations in PIK3CA enriched in signature 3. We observed improved overall survival (OS) for patients with signature 2 and worse OS for signatures 1 and 3. Twenty-eight percent of patients had CCNE1 amplification and this subset was enriched with carcinosarcoma histotype. Thirty-four percent of patients, across all histotypes, had ERBB2 amplification and/or HER2 overexpression on IHC, which was associated with worse outcomes. Mutations in PPP2R1A (29%) and FBXW7 (16%) were among the top 5 most common mutations. Conclusions: sWGS and targeted sequencing identified therapeutic opportunities in 75% of patients with p53abn endometrial cancer. Further research is needed to determine the efficacy of treatments targeting these identified pathways within p53abn endometrial cancers.

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

Abstract 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&amp;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.

Co-existent endometrial and ovarian carcinoma: molecular and pathological features define low risk entity

Most co-existent endometrial and ovarian carcinomas are clonally related and exhibit an indolent disease course. Pathologic assignment and clinical management of this entity vary greatly. The International Federation of Gynecology and Obstetrics (FIGO) 2023 endometrial carcinoma staging/risk stratification system introduced a new substage for co-existent endometrial and ovarian carcinomas that meet strict pathologic criteria (stage IA3, distinct from IIIA1). Our aim was to validate if FIGO IA3 identifies a subset of co-existent endometrial and ovarian carcinomas at very low risk of recurrence and determine whether further refinement, through molecular features and expanded ovarian pathologic criteria, could improve prognostic discernment and direct more patients for consideration of de-escalation. Clinicopathologic, molecular, and outcome data were collected on patients with co-existent endometrial and ovarian carcinoma, extracted from pathology archives and molecularly classified endometrial carcinoma cohorts. Among the 154 co-existent endometrial and ovarian carcinoma patients, higher recurrence rates were observed with the p53abn (2/6, 33%), mismatch repair deficiency (MMRd) (7/34, 21%) or no specific molecular profile (NSMP) estrogen receptor (ER) negative-low (2/15, 13%) molecular sub-types, compared with patients with POLEmut or NSMP ER strong positive tumors. Thirty-two patients met FIGO IA3 criteria, with one recurrence and death event (MMRd). Eliminating patients with adverse molecular features (p53abn or MMRd endometrium or ovary, or NSMP ER negative-low endometrium) and expanding criteria to include any POLEmut or cases with bilateral ovarian involvement, intra- or pre-operative ovarian rupture, or ovarian surface involvement significantly improved risk stratification (p = .008) and added 48 co-existent endometrial and ovarian carcinoma patients (>2-fold increase) with no recurrence events (mean follow-up: 6 years). There was 91% concordance of molecular sub-type assignment between endometrial and ovarian tumors. FIGO IA3 criteria identify a subset of co-existent endometrial and ovarian carcinomas with excellent outcomes. However, incorporating molecular features into the definition enables greater prognostic discernment and supports the inclusion of patients with a broader range of pathologic features with indolent disease (increased from 20% to 49% of the cohort, 0 recurrences) who may be candidates for treatment de-escalation.

Activated immune infiltrates expand opportunities for targeted therapy in p53‐abnormal endometrial carcinoma

AbstractTumor protein p53 mutated/abnormal (p53abn) endometrial carcinomas account for over 50% of deaths but comprise only 15% of all endometrial carcinomas. Most patients show limited response to standard‐of‐care chemotherapy with or without radiotherapy, and only a minority of cases are amenable to targeted therapies like poly‐ADP ribose polymerase (PARP) inhibitors and HER2‐directed therapies. Recent immunotherapy clinical trials have demonstrated remarkable efficacy, not only in mismatch repair deficient (MMRd) tumors but also in a subset of mismatch repair‐proficient (MMRp) tumors. However, the immune microenvironment and its relationship to other therapeutic targets in MMRp endometrial carcinoma remains poorly understood. Here, we characterize the immune microenvironment of p53abn endometrial carcinoma, the most clinically aggressive subtype of MMRp endometrial carcinoma, and correlate antitumor immune signatures with other targetable alterations. We accrued 256 treatment‐naïve p53abn endometrial carcinomas and systemically profiled T‐cell, B‐cell, myeloid, and tumor‐cell populations with multiplex immunofluorescence to assess the tissue localization and functional status of immune cells. Shallow whole‐genome sequencing was performed on a subset of 126 cases. Patterns of immune infiltration were compared to survival outcomes and mutational signatures. Mixture modeling divided p53abn endometrial carcinoma into tumor‐infiltrating lymphocyte (TIL)‐rich and TIL‐poor subsets. Over 50% of tumors were TIL‐rich. TIL‐rich cases overexpressed targetable immune evasion molecules and were associated with longer overall and disease‐specific survival in multivariate analysis. This effect was particularly pronounced in advanced stage disease and in patients who did not receive adjuvant chemotherapy. TIL did not associate with homologous recombination deficient mutational signatures or HER2 amplification. Our findings demonstrate a biological rationale for immunotherapy in a substantial subset of patients with p53abn endometrial cancer and may help inform combination therapies with immune checkpoint inhibition, PARP inhibitors, and anti‐HER2 agents. © 2025 The Author(s). The Journal of Pathology published by John Wiley &amp; Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Papillary and ductal patterns of mesonephric‐like adenocarcinomas are often overlooked: a retrospective revaluation of over 1000 endometrial carcinomas

AimsMesonephric‐like adenocarcinoma (MLA) of the endometrium is often a diagnostic challenge, due to its morphological resemblance to other more common Müllerian neoplasms. This study aimed to retrospectively identify overlooked MLA in a large endometrial carcinoma cohort, using a combination of immunohistochemistry (IHC), morphology and KRAS sequencing.Methods and resultsIHC was conducted on 1094 endometrial carcinomas, identifying 16 potential MLA cases based on GATA3+ and/or TTF1+ and ER− staining patterns, which subsequently underwent detailed histological review, KRAS sequencing and ProMisE molecular classification. Of the IHC screen‐positive cases, one was positive for both GATA3 and TTF1, nine were positive for GATA3 only and six were positive for TTF1 only. All IHC screen‐positive cases were POLE wild‐type. All five tumours in the NSMP category showed morphological features of MLA, while the three MMRd and eight p53abn tumours did not show MLA morphology. The five cases diagnosed as MLA on review were all originally diagnosed as low‐grade endometrioid adenocarcinoma probably because of rare morphological patterns, being predominantly papillary or ductal. Four of the five cases harboured a KRAS mutation.ConclusionThis study highlights the importance of a comprehensive diagnostic approach for accurately identifying endometrial MLA and for pathologists to be aware of papillary and ductal patterns in endometrial carcinoma assessment. Further exploration into the molecular landscape of MLA is essential for refining diagnostic criteria and developing targeted therapies.

Validation and clinical performance of a single test, DNA based endometrial cancer molecular classifier

We have previously shown that DNA based, single test molecular classification by next generation sequencing (NGS) (Proactive Molecular risk classifier for Endometrial cancer (ProMisE) NGS) is highly concordant with the original ProMisE classifier and maintains prognostic value in endometrial cancer. Our aim was to validate ProMisE NGS in an independent cohort and assess the performance of ProMisE NGS in real world clinical practice to address if there were any practical challenges or learning points for implementation. We evaluated DNA extracted from an external research cohort of 211 endometrial cancer cases diagnosed in 2016 from Germany, Switzerland, and Austria, across seven European centers, comparing standard molecular classification (NGS for A total of 545 endometrial cancers were compared. Prognostic differences in progression free, disease specific, and overall survival between the four molecular subtypes were observed for the NGS classifier, recapitulating the survival curves of original ProMisE. In 28 of 545 (5%) discordant cases (8/211 (4%) in the validation set, 20/334 (6%) in the real world cohort), molecular subtype was able to be definitively assigned in all, based on review of the histopathological features and/or additional immunohistochemistry. DNA based molecular classification identified twice as many 'multiple classifier' endometrial cancers; 37 of 545 (7%) compared with 20 of 545 (4%) with original ProMisE. External validation confirmed that single test, DNA based molecular classification was highly concordant (95%) with original ProMisE classification, with prognostic value maintained, representing an acceptable alternative for clinical practice. Careful consideration of reasons for discordance and knowledge of how to correctly assign multiple classifier endometrial cancers is imperative for implementation.

The cutoff for estrogen and progesterone receptor expression in endometrial cancer revisited: a European Network for Individualized Treatment of Endometrial Cancer collaboration study

There is no consensus on the cutoff for positivity of estrogen receptor (ER) and progesterone receptor (PR) in endometrial cancer (EC). Therefore, we determined the cutoff value for ER and PR expression with the strongest prognostic impact on the outcome. Immunohistochemical expression of ER and PR was scored as a percentage of positive EC cell nuclei. Cutoff values were related to disease-specific survival (DSS) and disease-free survival (DFS) using sensitivity, specificity, and multivariable regression analysis. The results were validated in an independent cohort. The study cohort (n = 527) included 82% of grade 1-2 and 18% of grade 3 EC. Specificity for DSS and DFS was highest for the cutoff values of 1-30%. Sensitivity was highest for the cutoff values of 80-90%. ER and PR expression were independent markers for DSS at cutoff values of 10% and 80%. Consequently, three subgroups with distinct clinical outcomes were identified: 0-10% of ER/PR expression with, unfavorable outcome (5-year DSS = 75.9-83.3%); 20-80% of ER/PR expression with, intermediate outcome (5-year DSS = 93.0-93.9%); and 90-100% of ER/PR expression with, favorable outcome (5-year DSS = 97.8-100%). The association between ER/PR subgroups and outcomes was confirmed in the validation cohort (n = 265). We propose classification of ER and PR expression based on a high-risk (0-10%), intermediate-risk (20-80%), and low-risk (90-100%) group.

Molecular classification in endometrial cancer: Opportunities for precision oncology in a changing landscape

Lay summary Endometrial carcinoma (EC) classification and risk stratification have undergone a global transformation in the last decade, shifting from a reliance on poorly reproducible histomorphological parameters such as grade and histotype, toward a molecular classification that is consistent and biologically informative. Molecular classification enables reliable categorization of ECs, provides prognostic information, and is now beginning to drive clinical management, including surgery and adjuvant therapy. Within this framework, we now have the ability to further refine both the prognostic and predictive value of molecular classification. As we move toward the routine implementation of this classification system as a stratification tool for research, clinical trials, and patient care, it is imperative that access to these tests be equitable. Furthermore, continued education will be critical for patients and providers to understand the value that this molecular information provides.

BRCA1Promoter Methylation and Clinical Outcomes in Ovarian Cancer: An Individual Patient Data Meta-Analysis

AbstractBackgroundBRCA1 methylation has been associated with homologous recombination deficiency, a biomarker of platinum sensitivity. Studies evaluating BRCA1-methylated tubal and ovarian cancer (OC) do not consistently support improved survival following platinum chemotherapy. We examine the characteristics of BRCA1-methylated OC in a meta-analysis of individual participant data.MethodsData of 2636 participants across 15 studies were analyzed. BRCA1-methylated tumors were defined according to their original study. Associations between BRCA1 methylation and clinicopathological characteristics were evaluated. The effects of methylation on overall survival (OS) and progression-free survival (PFS) were examined using mixed-effects models. All statistical tests were 2-sided.Results430 (16.3%) tumors were BRCA1-methylated. BRCA1 methylation was associated with younger age and advanced-stage, high-grade serous OC. There were no survival differences between BRCA1-methylated and non–BRCA1-methylated OC (median PFS = 20.0 vs 18.5 months, hazard ratio [HR] = 1.01, 95% CI = 0.87 to 1.16; P = .98; median OS = 46.6 vs 48.0 months, HR = 1.02, 95% CI = 0.87 to 1.18; P = .96). Where BRCA1/2 mutations were evaluated (n = 1248), BRCA1 methylation displayed no survival advantage over BRCA1/2-intact (BRCA1/2 wild-type non–BRCA1-methylated) OC. Studies used different methods to define BRCA1 methylation. Where BRCA1 methylation was determined using methylation-specific polymerase chain reaction and gel electrophoresis (n = 834), it was associated with improved survival (PFS: HR = 0.80, 95% CI = 0.66 to 0.97; P = .02; OS: HR = 0.80, 95% CI = 0.63 to 1.00; P = .05) on mixed-effects modeling.ConclusionBRCA1-methylated OC displays similar clinicopathological features to BRCA1-mutated OC but is not associated with survival. Heterogeneity within BRCA1 methylation assays influences associations. Refining these assays may better identify cases with silenced BRCA1 function and improved patient outcomes.

Proteomic analysis uncovers biological diversity in molecularly defined endometrial carcinomas

While endometrial cancer has an overall favorable prognosis, some patients have poor outcomes and may benefit from further refinements of the current classification systems. Molecular classification stratifies endometrial cancer patients into four prognostic subtypes: POLEmut, MMRd (mismatch repair deficient), p53abn, and NSMP (no specific molecular profile), where patients with POLEmut have the best prognosis and p53abn has the worst prognosis. We used proteomic profiling to assess if additional prognostic or predictive information could be identified across or within molecular subtypes. Global proteome profiling of formalin fixed, paraffin embedded samples, that had clinicopathologic and outcome data, was performed on 184 endometrial cancers encompassing all four molecular subtypes, including replicate samples of the same tumor, and both biopsy and final hysterectomy specimens. To ensure representation of each subtype, we profiled an approximately equal distribution in the 148 unique tumors; 34 (23%) POLEmut, 40 (27%) MMRd, 35 (24%) p53abn and 39 (26%) NSMP, rather than the population-based distributions. There was high reproducibility in the proteomic profiles of intra-tumor replicate samples, and between matched biopsy and hysterectomy tumor samples. Consensus clustering identified four clusters with different prognosis, named 'Adhesion', 'Immune', 'Proliferation', and 'Metabolic' based on the functional characteristics of the enriched proteins. We associated protein expression features with common mutations, molecular subtype, and outcomes. These results demonstrate the biologic diversity within endometrial cancers, both between and within molecular subtypes, and provide candidate features for functional and clinical investigation.

Challenges in implementation of molecular classification in early stage endometrial cancer—An NRG Oncology cooperative group mixed‐methods study

AbstractBackgroundProfessional guidelines recommend molecular profiling for mismatch repair (MMR), p53, and polymerase epsilon (POLE) status in endometrial cancer (EC). However, adoption in the United States has not been documented, and barriers to the implementation of testing have not been described.MethodsIn this mixed‐methods study, implementation science frameworks were used to develop a quantitative survey. Gynecologic oncologists, medical oncologists, radiation oncologists, and pathologists affiliated with NRG Oncology programs were contacted through snowball sampling and were surveyed during 2022–2023. A subset of respondents was interviewed. Statistical and thematic analyses were performed.ResultsAt least 403 NRG Oncology‐affiliated providers were contacted for the survey, and 107 (26.6%) responded. Greater than 90% of respondents perceived POLE, MMR, and p53 status as important for clinical care. MMR and p53 tests were perceived as easy to obtain, but only 24.2% of respondents reported that POLE testing was moderately or very easy to obtain. Respondents from academic sites reported better access to molecular classification and perceived greater importance of molecular classification compared with respondents from community sites. In thematic analysis of 13 qualitative interviews, cost concerns were reported as large barriers to testing. Interviewees reported a desire for prospective data to guide treatment selection based on classification results.ConclusionsAlthough integrating molecular classification into standard pathologic reporting is recommended, and clinicians perceive molecular profiling in early stage EC as important, survey respondents noted significant implementation barriers. Implementation challenges that differ between community oncology and academic practice settings were identified. Strategies to improve equitable access to molecular classification of early stage EC are needed.

Improving Specificity for Ovarian Cancer Screening Using a Novel Extracellular Vesicle–Based Blood Test

The low incidence of ovarian cancer (OC) dictates that any screening strategy needs to be both highly sensitive and highly specific. This study explored the utility of detecting multiple colocalized proteins or glycosylation epitopes on single tumor-associated extracellular vesicles from blood. The novel Mercy Halo Ovarian Cancer Test (OC Test) uses immunoaffinity capture of tumor-associated extracellular vesicles, followed by proximity-ligation real-time quantitative PCR to detect combinations of up to three biomarkers to maximize specificity, and measures multiple combinations to maximize sensitivity. A high-grade serous carcinoma (HGSC) case-control training set of EDTA plasma samples from 397 women was used to lock down the test design, the data interpretation algorithm, and the cutoff between cancer and noncancer. Performance was verified and compared with cancer antigen 125 in an independent blinded case-control set of serum samples from 390 women (132 controls, 66 HGSC, 83 non-HGSC OC, and 109 benign). In the verification study, the OC Test showed a specificity of 97.0% (128/132; 95% CI, 92.4%-99.6%), a HGSC sensitivity of 97.0% (64/66; 95% CI, 87.8%-99.2%), and an area under the curve of 0.97 (95% CI, 0.93-0.99) and detected 73.5% (61/83; 95% CI, 62.7%-82.6%) of the non-HGSC OC cases. This test exhibited fewer false positives in subjects with benign ovarian tumors, nonovarian cancers, and inflammatory conditions when compared with cancer antigen 125. The combined sensitivity and specificity of this new test suggests that it may have potential in OC screening.

AI-based histopathology image analysis reveals a distinct subset of endometrial cancers

Abstract Endometrial cancer (EC) has four molecular subtypes with strong prognostic value and therapeutic implications. The most common subtype (NSMP; No Specific Molecular Profile) is assigned after exclusion of the defining features of the other three molecular subtypes and includes patients with heterogeneous clinical outcomes. In this study, we employ artificial intelligence (AI)-powered histopathology image analysis to differentiate between p53abn and NSMP EC subtypes and consequently identify a sub-group of NSMP EC patients that has markedly inferior progression-free and disease-specific survival (termed ‘p53abn-like NSMP’), in a discovery cohort of 368 patients and two independent validation cohorts of 290 and 614 from other centers. Shallow whole genome sequencing reveals a higher burden of copy number abnormalities in the ‘p53abn-like NSMP’ group compared to NSMP, suggesting that this group is biologically distinct compared to other NSMP ECs. Our work demonstrates the power of AI to detect prognostically different and otherwise unrecognizable subsets of EC where conventional and standard molecular or pathologic criteria fall short, refining image-based tumor classification. This study’s findings are applicable exclusively to females.

VOLTA: an enVironment-aware cOntrastive ceLl represenTation leArning for histopathology

Abstract In clinical oncology, many diagnostic tasks rely on the identification of cells in histopathology images. While supervised machine learning techniques necessitate the need for labels, providing manual cell annotations is time-consuming. In this paper, we propose a self-supervised framework (enVironment-aware cOntrastive cell represenTation learning: VOLTA) for cell representation learning in histopathology images using a technique that accounts for the cell’s mutual relationship with its environment. We subject our model to extensive experiments on data collected from multiple institutions comprising over 800,000 cells and six cancer types. To showcase the potential of our proposed framework, we apply VOLTA to ovarian and endometrial cancers and demonstrate that our cell representations can be utilized to identify the known histotypes of ovarian cancer and provide insights that link histopathology and molecular subtypes of endometrial cancer. Unlike supervised models, we provide a framework that can empower discoveries without any annotation data, even in situations where sample sizes are limited.

The Progesterone Challenge Test as a Functional Biomarker of Endometrial Cancer Risk: Results from a Prospective Feasibility Study

Abstract Endometrial cancer incidence continues to increase globally, driven mainly by obesity. Current diagnostic pathways rely on symptom presentation; no validated approach exists to identify asymptomatic individuals who may benefit from targeted prevention. The progesterone challenge test (PCT) is a physiologic assessment of endometrial hormonal responsiveness that could pragmatically guide endometrial cancer prevention interventions. The RESToRE study (NCT05651282) prospectively assessed the feasibility of the PCT as a community-based risk-stratification tool for endometrial cancer prevention in British Columbia, Canada, between 2023 and 2024. Asymptomatic postmenopausal participants, defined by the absence of vaginal bleeding, with body mass index ≥34.9 kg/m2 and an intact uterus, completed a 10-day course of oral medroxyprogesterone acetate (MPA) 10 mg daily. Feasibility, tolerability, and acceptability were evaluated. Of 96 eligible individuals, 68 enrolled, 53 initiated, and 51 completed the PCT. Sixteen participants experienced withdrawal bleeding (+PCT; 30.2% of those with evaluable results). All +PCT individuals were referred to a gynecologist for standard-of-care evaluation, including an endometrial biopsy. Among the 15 who underwent biopsy, two had a proliferative endometrium, and one had simple hyperplasia. Participants and providers found the test acceptable, citing its simplicity and low administrative burden. Side effects of the PCT were mild (median severity ≤three of 10), resulting in 3.8% (two of 53) of participants discontinuing the MPA. The PCT was feasible, well-tolerated, and acceptable among higher-risk postmenopausal individuals, supporting its use as a physiologic, functional biomarker of endometrial responsiveness. These findings provide early evidence for a scalable, low-cost strategy to identify individuals likely to benefit from targeted endometrial cancer prevention. Prevention Relevance: This study demonstrates that the PCT is feasible and acceptable as a functional biomarker associated with the risk of endometrial cancer in asymptomatic postmenopausal individuals with obesity. As a low-cost, scalable, community-deliverable approach, our findings support validation of this test in the context of endometrial cancer precision prevention.

Molecular Classification in Relation to Prevention of Endometrial Cancer Recurrence and Lifestyle Factors

Endometrial cancer (EC) is one of the most prevalent cancers in women worldwide with a significantly increasing incidence, especially in developed countries. One of the reasons for the increase in the incidence of this disease is the rising incidence of obesity as the biggest risk factor for the development of this disease. Other important risk factors are hypertension, diabetes mellitus and the general ageing of the population. These risk factors are not only associated with a higher risk of developing the disease, but also, for example, with post-operative complications affecting the quality of life of patients after surgery. The molecular classification of endometrial cancer, which has been introduced into clinical practice in recent years, is currently helping physicians to make treatment decisions for individual patients and predict prognosis. In this project, we would like to focus on the relationship of this molecular classification with genomic mutational signatures detected by whole-exome sequencing and their association with lifestyle risk factors for endometrial cancer (obesity - BMI, hypertension, diabetes mellitus), including the extent of staging lymphadenectomy. Identification and detailed analysis of dominant mutational profiles associated with a specific molecular subtype of EC and their influence on the presence of lifestyle risk factors may have a major impact on both disease development and prevention of disease recurrence. The possible relationship of the mutational profile with the extent of staging lymphadenectomy may help in deciding the extent of this surgical procedure, which subsequently affects the quality of life of patients, especially in patients with high BMI. Given the widespread prevalence of lifestyle risk factors in the developed world, a detailed understanding of the relationship between the genetic profile, its alterations and the prevalence of these risk factors, with potentially major implications for treatment success, is crutial.