Clinicopathological and molecular characterisation of 'multiple-classifier' endometrial carcinomas

Establishing a comprehensive panel of patient-derived xenograft models for high-grade endometrial carcinoma: molecular subtypes, genetic alterations, and therapeutic target profiling

BACKGROUND

High-grade endometrial cancer (EC) has a poor prognosis, but molecular classification-based treatments present new therapeutic opportunities. Antibody-drug conjugates (ADC) emerge as promising tools, yet a deeper understanding of antigen dynamics, optimal therapeutic sequencing, and resistance mechanisms is essential. This study investigates the utility of patient-derived xenograft (PDX) models for EC as preclinical platforms, evaluating molecular subtypes and the ADC targets expression of patient and PDX tumors.

METHODS

We developed a comprehensive panel of molecularly characterized PDX models from patients with EC representing various histological types. Molecular subtypes and gene alterations were analyzed using sequencing and immunohistochemistry. ADC targets, including human epidermal growth factor receptor 2, trophoblast cell-surface antigen 2, B7-H4, folate receptor alpha, and cadherin-6, were profiled.

RESULTS

Thirty-one EC-PDX models were successfully established, maintaining histological fidelity and 93.1 % molecular subtype consistency with the patient tumors. Notably, 80.6 % of the PDX models exhibited high expression (2+/3+) of at least one ADC target, and 54.8 % displayed high expression of multiple targets. Remarkably, 9.7 % showed high expression of all targets, with gene mutations also characterized. Meanwhile, patient tumors, 78.8 % showed high expression (2+/3+) of at least one ADC target, and 63.6 % showed high expression of multiple targets.

CONCLUSION

The molecularly classified EC-PDX panel, enriched with detailed antigen profiles and genetic data, provides a robust platform for investigating novel ADC therapies and precision treatment strategies for high-grade EC.

Prediction of molecular subtypes of endometrial cancer patients on the basis of intratumoral and peritumoral radiomic features from multiparametric MR images

OBJECTIVES

The purpose of this study was to assess the performance of multiparametric MRI-based radiomic models in predicting the molecular subtypes of endometrial cancer (EC) patients.

METHODS

A total of 310 patients with pathologically confirmed EC who underwent preoperative MRI were enrolled this retrospective study and randomly divided into training (n = 217) and testing (n = 93) cohorts. We extracted 22,640 radiomic features from intratumoral and 3-mm peritumoral regions of interest (ROIs) on MR images. Feature selection was performed using the Mann-Whitney U test, Max-Relevance and Min-Redundancy (mRMR) and the least absolute shrinkage and selection operator (LASSO). Twelve radiomic signatures (RSs) were constructed using logistic regression to predict four molecular subtypes (POLEmut, MMRd, NSMP, and p53abn). The performance of these RSs was assessed using receiving operating characteristic (ROC) curve analysis, and the area under the curve (AUC), sensitivity, specificity, and accuracy were calculated.

RESULTS

In the testing cohort, the RSs based on intratumoral features for predicting the POLEmut, MMRd, NSMP and p53abn subtypes yielded AUCs of 0.764, 0.812, 0.893 and 0.731, respectively, whereas those based on peritumoral features yielded AUCs of 0.847, 0.836, 0.871 and 0.804, respectively. The RSs constructed by combining intratumoral and peritumoral features for predicting the POLEmut, MMRd, NSMP and p53abn subtypes had the AUCs of 0.844, 0.880, 0.943 and 0.801, respectively.

CONCLUSION

The combination of intratumoral and peritumoral radiomic features from multiparametric MRI enables effective and noninvasive prediction of EC molecular subtypes.

Patterns of primary metastasis and recurrence in mismatch repair deficiency and p53 abnormal endometrial carcinoma

OBJECTIVES

Molecular classification of endometrial carcinoma(EC) provides relevant prognostication and is now being utilized to determine adjuvant therapy. It is currently unclear how molecular classification relates to disease dissemination and recurrence patterns in EC. The objective of this study was to characterize patterns of disease in mismatch repair-deficient (MMRd) and p53 abnormal (p53abn) carcinomas.

METHODS

Immunohistochemistry molecular classification was performed to relate patterns of disease spread among EC patients undergoing surgical staging/cytoreduction. Dissemination patterns were assigned according to the most distant site of disease and subdivided as carcinomatosis, visceral organ, or lymphatic locations. Standard statistical methods were employed for comparisons, including multivariate logistic regression.

RESULTS

Of 380 cases, 127 had advanced disease at presentation: 43.4 % pelvic, 44.8 % lower abdominal, 7.1 % upper abdominal and 4.7 % extra-abdominal. P53abn carcinomas were more likely to present with peritoneal-based disease compared to MMRd and p53wt tumors(30.8 %, 11.7 %, and 9.7 %, p < 0.0001). Among 128 patients with recurrence, upper abdominal spread and carcinomatosis were more common with p53abn than MMRd or p53wt tumors(49.2 %, 10 %, 8.2 %, p < 0.0001 and 60.8 %, 7.5 %, 18.9 %, p < 0.0001). MMRd tumors were associated with lymphatic recurrences compared to p53abn or p53wt(55 %, 19.6 %, 35.1 %, p = 0.001). These associations remained significant in multivariate analysis.

CONCLUSIONS

EC recurrence patterns differ based on molecular classification. Patients with p53abn cancers are more likely to present with peritoneal-based disease and experience peritoneal recurrence. Patients with MMRd cancers are more likely to experience lymphatic-based recurrences. This information provides a model of biologic behavior of molecular subtypes that can inform prospective surgical and therapeutic trials.

Are all mismatch repair deficient endometrial cancers created equal? A large, retrospective, tertiary center experience

BACKGROUND

One third of endometrial carcinomas (ECs) presents with mismatch repair deficiency (MMRd). Of these, 70 % are caused by somatic hypermethylation of MLH1 promoter; the remaining cases are determined by Lynch syndrome or double somatic inactivation of MMR genes. Although associated with good-intermediate prognosis, heterogeneity in treatment response and survival has been reported among MMRd ECs. We aim to investigate differences in pathologic aggressiveness and event-free survival (EFS) among three MMRd EC subtypes, classified by immunohistochemistry (IHC) and MLH1 methylation analysis.

METHODS

Subjects undergone surgical staging for EC were retrospectively included. IHC analysis was performed in all patients to assess MMR and p53 status. Methylation analysis was performed in MMRd patients with IHC-negative MLH1. The MMRd population was classified into: 1)MLH1-hypermethylated (MLH1-HyMet); 2)MLH1-unmethylated (MLH1-UnMet); 3)IHC-negative MSH2 and/or MSH6 or PMS2 alone (non-MLH1).

RESULTS

Of 1171 patients undergoing surgical staging and IHC assessment, 362 (30.9 %) were classified as MMRd and included in the analysis. Among these, 59.7 % (n = 216) were MLH1-HyMet, 11 % (n = 40) MLH1-UnMet, and 29.3 % (n = 106) non-MLH1. Compared to MLH1-UnMet and non-MLH1, MLH1-HyMet was associated with older age, higher BMI, larger tumor size, deeper myometrial invasion, substantial lymphovascular space invasion, lower frequency of early-stage and low-risk disease. EFS was similar when comparing the MMRd subtypes, even after adjusting for stage and tumor histology. However, a trend of MLH1-HyMet toward poorer prognosis can be observed, particularly in the advanced/metastatic setting.

CONCLUSIONS

MLH1-hypermethylated MMRd ECs display more aggressive clinicopathologic features compared to the other MMRd subgroups. However, although a suggestive trend toward poorer EFS was observed in the hypermethylated subset, particularly in the advanced setting, no significant differences in prognosis were detected among the MMRd subtypes.

Molecular subtypes and genomic landscape of undifferentiated and dedifferentiated endometrial cancer

OBJECTIVE

Undifferentiated and dedifferentiated endometrial carcinomas are rare and clinically aggressive variants of the disease. We sought to define the molecular subtypes and genetic alterations affecting cancer-related genes of these rare histologic endometrial cancer types.

METHODS

Patients with undifferentiated/dedifferentiated endometrial cancer subjected to clinical tumor-normal panel sequencing between January 1, 2014, to June 1, 2023, were retrospectively identified, and relevant demographic and clinicopathologic data were extracted from medical records. All cases underwent central pathology review. Endometrial carcinomas with mixed histology and synchronous tumors were excluded. Genomic data including somatic mutations, copy number alterations, and microsatellite instability (MSI), in addition to immunohistochemistry results, were extracted and utilized for molecular subtyping.

RESULTS

A total of 35 patients met inclusion criteria, with a median age at diagnosis of 60 years (range, 36 to 85). Of these, 16 (46%) were undifferentiated and 19 (54%) dedifferentiated, with undifferentiated being more frequently of International Federation of Obstetrics and Gynecology (FIGO) 2009 stage IV at diagnosis than dedifferentiated (7/16, 40% vs 3/19, 17%, p = .05). All 4 molecular subtypes were present, with the majority being MSI-high/mismatch repair-deficient (n = 25, 71%); the remaining cases were of POLE molecular subtype (n = 2, 6%), copy number (CN)-high/TP53abnormal (n = 3, 9%), and CN-low/no specific molecular profile (n = 5, 14%). The most recurrent genetic alterations were found in PTEN (26/35, 74%), ARID1A (26/35, 74%), PIK3CA (21/35, 60%) ARID1B (14/35, 40%), and SMARCA4 (9/35, 26%). Pathogenic mutations in chromatin remodeling genes, including ARID1A and ARID1B, were absent in endometrial cancers of CN-high/TP53abnormal subtype.

CONCLUSIONS

Undifferentiated/dedifferentiated endometrial cancers are heterogeneous at the molecular level; however, the majority are MSI-high/mismatch repair-deficient, which may have therapeutic implications. Loss-of-function alterations in chromatin remodeling genes were present in all molecular subtypes except CN-high/TP53 abnormal undifferentiated/dedifferentiated endometrial cancers.

Molecular subgroup-specific prognostic value of semiquantitative lymphovascular space invasion in early-stage endometrioid endometrial cancer

OBJECTIVE

Molecular subgroups of endometrial carcinoma represent distinct disease entities, prompting subgroup-specific stratification. Recognizing lymphovascular space invasion (LVSI) as a key parameter in risk assessment, this study evaluates 3-tiered LVSI as a molecular subgroup-specific prognostic factor in stage I-II endometrioid endometrial cancer.

METHODS

This retrospective study included patients treated at a single tertiary center. Immunohistochemistry and polymerase-ϵ (POLE) sequencing were conducted for molecular classification and determination of estrogen receptor and L1 cell adhesion molecule (L1CAM) expression.

RESULTS

Among 843 eligible patients (median follow-up: 70 months), survival outcomes differed by molecular subgroup (P < 0.001 for progression-free survival and disease-specific survival). In MMRd carcinomas (n = 364), both focal (P < 0.001) and substantial (P < 0.001) LVSI were associated with poor progression-free survival. In NSMP carcinomas (n = 359), only substantial LVSI (P < 0.001) was prognostic (focal: P = 0.480). In p53abn carcinomas (n = 62), neither focal (P = 0.248) nor substantial (P = 0.484) LVSI showed prognostic significance. These findings remained after bivariate adjustments for stage (IA vs. IB vs. II), grade (low vs. high), estrogen receptor expression (3-tiered scale), L1CAM expression, age, and adjuvant therapy. Analysis was unfeasible for POLE ultramutated tumors (n = 58) due to a single progression.

CONCLUSION

The prognostic impact of 3-tiered LVSI varied by molecular subgroup in stage I-II endometrioid endometrial cancer, highlighting the need for subgroup-specific risk assessment to improve individualized counceling on treatment decisions and risk of progression.

Improved Prognostic Stratification With 2023 International Federation of Gynecology and Obstetrics Staging in Endometrial Cancer Reflecting Poor Prognosis of Aggressive Histological Types and p53 Abnormality

This study compares the distribution and prognostic impact of the 2009 and 2023 International Federation of Gynecology and Obstetrics (FIGO) staging systems for endometrial cancer and their impact on the 2022 European Society for Medical Oncology (ESMO) risk classification. Patients were restaged according to the 2009 FIGO staging system, the 2023 FIGO staging system, and the 2023 FIGO staging system with molecular classification. Risk groups were assigned according to the 2022 ESMO guidelines using each staging system. Among 679 patients, 139 (20.5%) experienced stage migration when transitioning from the 2009 FIGO staging system to the 2023 FIGO staging system with molecular classification, with 121 (17.8%) upstaged and 18 (2.7%) downstaged. Most changes were from FIGO stage I to stage II, primarily due to p53 abnormality, aggressive histological type, or extensive/substantial lymphovascular space invasion. Hazard ratios for overall survival, disease-free survival, and event-free survival increased with advancing stage groups in all systems, showing the greatest differences when the 2023 FIGO staging system with molecular classification was used. The newly introduced FIGO stages IC, IIC (both representing aggressive histological types), and IICmp53abn (associated with p53 abnormality) in the 2023 FIGO staging system were associated with worse outcomes, similar to FIGO stage III. The prognostic predictability of the 2022 ESMO risk group was minimally affected by the transition from the 2009 FIGO to the 2023 FIGO staging system, as the factors introduced in the new FIGO system were already incorporated into the 2022 ESMO risk classification. Only 17 (2.5%) patients experienced a change in their assigned risk group. The 2023 FIGO staging system showed improved prognostic stratification over the 2009 FIGO staging system, particularly by reflecting the poor prognosis of aggressive histological types and p53 abnormality.

Molecular subtyping of endometrial cancer via a simplified one-step NGS classifier, ARID1A and ZFHX4 mutations help further subclassify CNL/MSI-H patients

BACKGROUND

Molecular subtyping has changed the prognostic stratification and therapeutic guidance for patients with endometrial cancer (EC). However, simultaneous application of sanger sequencing and immunohistochemistry under ProMisE criteria may be time- and tissue-consuming. This study attempted to measure subtype-specific biomarkers by one-step next-generation sequencing (NGS) resulting in a shorter turnaround time and less requirement of tissue samples.

METHODS

FFPE samples from 233 EC patients were retrospectively collected. Overall survival (OS) information was available for 131 patients with a median follow-up of 66 months. Genomic DNA was extracted and subjected to a one-step NGS panel including TP53, POLE and MSI measurement. Further comprehensive genomic analyses were performed on DNA from MSI-H and copy number low (CNL) subtypes.

RESULTS

The molecular typing ratio of the 233 patients was 8.15% for POLE subtype, 18.88% for MSI-H subtype, 11.59% for copy number high (CNH) subtype and 61.37% for CNL subtype. The 10-year OS and disease-specific survival (DSS) rate was 100% in POLE subtype, while only 33.51% and 39.69% in CNH subtype. In patients with CNL and CNL/MSI-H subtypes, ARID1A and ZFHX4 mutations were significantly associated with worse prognosis respectively.

CONCLUSION

This simplified one-step NGS panel can effectively subgroup EC patients into four prognostically different subtypes. New biomarkers are able to potentially refine the classification of patients with CNL/MSI-H subtypes into groups with distinct clinical outcomes.

The Value of Integrating Hormone Receptors into Immunohistochemistry-Based Simplified Molecular Classification in Endometrial Cancer

Purpose

To explore the clinical utility of immunohistochemistry (IHC)-based molecular classification and evaluate the distribution patterns and clinical implications of hormone receptor (HR) expression across different molecular classifications in endometrial cancer (EC).

Patients and Methods

This study retrospectively conducted simplified molecular classification based on IHC analysis of mismatch repair (MMR) and p53 protein from 322 EC patients admitted to the Obstetrics and Gynecology Department of Tianjin Medical University General Hospital from March 2017 to April 2024. 121 patients underwent WHO molecular classification by gene sequencing and IHC analysis. The application value of IHC-based simplified molecular classification was evaluated. The association between HR expression and molecular classification, and their combined value in predicting survival were analyzed.

Results

In IHC-based simplified molecular classification, 23.3% (75/322), 59.9% (193/322), and 16.8% (54/322) patients were included in the MMR deficient (MMRd) group, MMR proficient (MMRp) group, and p53-abnormal (p53abn) group, respectively. This classification correlated significantly with various clinicopathological features such as age (p=0.001), body mass index (p=0.016), FIGO stage (p=0.002), histological subtype (p<0.001), and tumor differentiation (p<0.001). Furthermore, differences in disease-free survival (DFS) among these groups were statistically significant (p=0.002). Subgroup analyses revealed that HR expressions significantly affected DFS within molecular classification groups. Patients with positive estrogen receptor (ER) or progesterone receptor (PR) expression demonstrated better DFS than those with negative expression in these groups (ER in MMRp: p<0.001, PR in MMRp: p<0.001, ER in MMRd: p<0.001, PR in MMRd: p=0.032, ER in p53abn: p=0.052, PR in p53abn: p=0.019).

Conclusion

IHC-based simplified molecular classification is an economically viable and clinically applicable method that effectively stratifies patients by clinicopathological features and prognosis. Moreover, this approach allows stratification into different prognostic risk groups based on HR expression in molecular classification subgroups.

Mesonephric-like adenocarcinoma of the female genital tract: Pathologic diagnosis, clinical outcomes, and novel therapeutics

In 2016, McCluggage and colleagues first defined mesonephric-like adenocarcinoma (MLA) of the uterus and extra-uterine sites. Following this initial description, the World Health Organization officially recognized MLA as a type of uterine and ovarian carcinoma and subsequent studies have further refined the morphologic definition, immunohistochemical profile, molecular underpinnings, and clinical behavior in this rare entity. A consortium of pathologists, gynecologic oncologists, medical oncologists, radiation oncologists, as well as basic science collaborators with expertise in MLA was convened to develop consensus regarding the pathologic diagnosis, and to identify unanswered questions and priority areas for research. Here, we review the current understanding of MLA from a pathologic, molecular, and clinical standpoint.

Comparative analysis of European guideline-based clinicopathological risk groups and the International Federation of Gynecology and Obstetrics staging system for endometrial cancer

OBJECTIVE

To investigate the correlation between endometrial cancer risk groups, as defined by the 2021 European guidelines, and the 2023 International Federation of Gynecology and Obstetrics (FIGO) staging system. Further, we aimed to evaluate the additional prognostic capability of the staging system within individual risk groups.

STUDY DESIGN

This retrospective cohort study included patients who underwent primary treatment for endometrial cancer at a single tertiary center. Each case was classified into a molecular-integrated risk group according to the 2021 joint guidelines from the European Society of Gynaecological Oncology (ESGO), the European Society for Radiotherapy and Oncology (ESTRO), and the European Society of Pathology (ESP). Staging was performed using the FIGO 2023 criteria with molecular classification.

RESULTS

Data from 1044 patients were analyzed. Median follow-up was 70 months. Stage IA2, stage IB, and stage IVB were the most prevalent stages among the ESGO-ESTRO-ESP low-risk, intermediate risk, and advanced-metastatic groups, accounting for 80 %, 75 %, and 54 % of the cases, respectively. The stage distribution was more heterogeneous in the high-intermediate risk and high-risk groups, with stage IIA comprising 36 % and stage IICmp53abn comprising 35 % of cases in these groups. The FIGO staging system further stratified survival outcomes especially in the high-intermediate and high-risk groups. Stage IIC included a substantial number of cases from the intermediate risk (n = 23), high-intermediate risk (n = 48), and high-risk (n = 27) groups. Risk groups were associated with survival within this stage.

CONCLUSIONS

ESGO-ESTRO-ESP high-intermediate risk and high-risk endometrial cancers exhibited the greatest variability in terms of stage distribution and survival outcomes. Stage IIC, the most heterogeneous stage concerning risk groups, showed an association between risk groups and survival.

The association of molecular classification with fertility-sparing treatment of atypical endometrial hyperplasia and endometrial cancer: a retrospective study

Background

To evaluate whether molecular classification was associated with treatment response and recurrence in women with atypical endometrial hyperplasia (AEH) or early-stage endometrial cancer (EC) treated with progestin.

Methods

A retrospective analysis of 116 patients (71 AEH and 45 EC) who received fertility-sparing therapy between 2010 and 2022 was performed. Tumors were classified via immunohistochemistry and gene sequencing into four subgroups: polymerase-ϵ (POLE)-mutated (POLEmut), tumor protein 53 (p53) wild type [p53wt; no specific molecular profile (NSMP)], mismatch repair deficient (MMRd), and p53 abnormal (p53abn). The primary outcome was complete response (CR) to hormone therapy. The secondary outcomes included the recurrence rate after CR and conception success. The treatment response to progestin and recurrence rate were compared across the four subgroups.

Results

Of 116 patients, 10 (8.62%) were classified as POLEmut, 81 (69.82%) p53wt, 9 (7.76%) p53abn, and 16 (13.76%) MMRd. At the 12-month evaluation, 87 patients (75.00%) achieved CR (median treatment duration, 5.95 months; range, 1.6-12.9). Partial response (PR), stable disease (SD), and progressive disease (PD) rates were 6.89% (n = 8), 1.72% (n = 2), and 16.38% (n = 19), respectively. Patients with the p53abn and MMRd subtypes had lower CR rates (33.33% and 37.50%) and higher progression rates (44.40% and 37.50%) compared to other subgroups (p < 0.05). After 24-month follow-up, recurrence rates were markedly higher in the p53abn (100%) and MMRd (83.33%) subgroups versus the POLEmut (33.33%) and p53wt (17.39%) subgroups (p < 0.05). Among 56 (64.37%) patients attempting conception, the pregnancy rate of 38 patients who received in vitro fertilization-embryo transfer was 47.37% (18/38), and the pregnancy rate of 18 patients who chose natural pregnancy was 16.67% (3/18), showing no statistical difference (p = 0.072).

Conclusion

Molecular classification may be associated with hormone treatment response in patients with AEH, EC patients with POLEmut and p53wt had better progestin response, and those with MMRd and p53abn had the poorest response and the highest recurrence rate. Recurrence was common after CR, but close review is necessary. For further investigation of the role of molecular classification in fertility-sparing treatment of AEH/EC, larger prospective studies are necessary.

The prognostic implication of polymerase epsilon-mutated endometrial cancer

The traditional classification and risk stratification systems of endometrial cancer (EC), which relied on histomorphological features, were limited and poor reproducible. The classification of new molecular subtypes of EC has been developing, including The Cancer Genome Atlas (TCGA)-four molecular subtypes: Polymerase epsilon (POLE) mutation (POLEmut), microsatellite instability hypermutated, copy number-low, and copy number-high and ProMisE-four molecular subtypes: POLEmut, mismatch repair deficiency, no specific molecular profile, and p53 abnormal. POLEmut usually correlates with a favorable outcome. Hence, we reviewed the research since the TCGA molecular subtypes developed in 2013 and summarized the characteristics and prognosis of POLEmut EC patients. In summary, we found POLEmut occurs in 7.3%-9.6% of EC in the previous studies. POLEmut EC consistently exhibits favorable patient outcomes, regardless of adjuvant therapy. The research of POLEmut in EC is absent in Taiwan, and the underlying mechanisms and cost-effectiveness need further investigation.

New FIGO 2023 Staging System of Endometrial Cancer: An Updated Review on a Current Hot Topic

The International Federation of Gynaecology and Obstetrics (FIGO) introduced a new staging system for endometrial carcinoma FIGO 2023 in June 2023. The new staging system differs significantly from previous versions by incorporating other non-anatomical parameters (histological type of tumour, tumour grade and the presence of massive lymphovascular space involvement as well as the molecular classification of the tumour). The FIGO 2023 staging system enhances the accuracy of prognostic assessments for patients at a specific stage with better options for targeted treatment. Another objective was to synchronise staging as much as possible with the European oncogynaecological ESGO/ESTRO/ESP guidelines for the management of patients with endometrial carcinoma established in 2021. However, several changes are controversial. Routine molecular classification of endometrial carcinomas is not yet commonly available in most countries of the world. Another limitation of the FIGO 2023 staging system of endometrial cancer is the inclusion of variables whose definitions are still evolving, as well as variables that are subject to considerable interobserver variability in their assessment. Advantages, controversies, and limitations for clinical practice of the new FIGO 2023 endometrial cancer staging system are discussed.

Clinicopathological and Molecular Characterization of Non-Endometrioid Endometrial Carcinoma

Objective: Molecular classification has become an essential tool in endometrial carcinoma; however, its application in non-endometrioid carcinoma (NEEC), particularly rare histological subtypes, remains relatively unexplored. This study aims to investigate the potential utility of molecular classification in NEEC. Methods: A retrospective analysis was conducted on 167 NEEC cases diagnosed at the Women's Hospital of Zhejiang University from 2013 to 2020. The cases were categorized into four molecular subtypes: POLE ultra-mutated (POLEmut), mismatch repair-deficient (MMRd), p53-abnormal (p53abn), and no specific molecular profile (NSMP) molecular subgroups. Statistical significance was set at P<0.05. Results: Among the cases, 13 (7.8%) patients were classified as POLEmut, 25 (15.0%) as MMRd, 84 (50.3%) as p53abn, and 45 (27.0%) as NSMP. Most POLEmut cases were at early stages (11/13, 84.6% at stages I-II), whereas p53abn cases were predominantly at advanced stages (32/49, 65.3% at stages III-IV). Additionally, p53abn was the most common subtype in serous carcinoma (41/45, 91.1%) and mixed adenocarcinoma (24/57, 42.1%). The 3-year recurrence-free survival (RFS) rates for POLEmut, MMRd, NSMP, and p53abn were 100.0%, 88.0%, 73.3%, and 71.4% , respectively. The 3-year overall survival (OS) rates were 100.0%, 88.0%, 82.2%, and 73.8%, respectively. Univariate analysis revealed significant associations of age ≥60 years (P=0.01), hypertension (P=0.03), FIGO stage (P<0.001), lymphovascular space invasion (P=0.01), lymph node metastasis (P<0.001), myometrial invasion (P<0.001), and postoperative adjuvant therapy (P=0.01) with 3-year RFS. Multivariate analysis identified age ≥60 years (P=0.03), myometrial invasion (P=0.01), and FIGO stage (P=0.046) as independent risk factors for 3-year OS. Conclusion: Molecular classification is crucial for accurately predicting the prognosis of NEEC, enabling more tailored treatment approaches in clinical practice. Furthermore, patient age may have a significant influence on NEEC classification and progression.

MiR-205-5p and MiR-222-3p as Potential Biomarkers of Endometrial Cancer

Endometrial cancer is the fourth most common cancer in women in Europe. Its carcinogenesis is a complex process and requires further research. In our study, we focus on finding new and easy-to-diagnose markers for detecting endometrial cancer. For this purpose, we compared the levels of miR-21-5p, miR-205-5p, and miR-222-3p in endometrial cancer tissues with the levels of these miRs in the serum of patients using the dPCR method. Our study is preliminary and consists of comparing the changes in miRNA expression in serum to the changes in miRNA in tissue of patients with endometrial cancer. The study included 18 patients with EC and 19 patients undergoing surgery for pelvic organ prolapse or uterine fibroids as a control group without neoplastic lesions. Endometrial tissue and serum were collected from all patients. The analyses showed an increased expression of miR-205-5p in endometrial cancer tissue and decreased expression of miR-222-3p in tissue and serum samples. These results suggest that miR-205-5p and miR-222-3p may be potential endometrial cancer biomarkers. Only miR-222-3p confirmed its decreased expression in serum, making it a potential and easily accessible marker in the diagnosis of endometrial cancer. This pilot study requires further investigation in a larger group of patients. Its advantages include the possibility of a comparison between miRNA expression in tissue and serum, as well as conducting the study using dPCR.

Low-Grade Endometrial Cancer with Abnormal p53 Expression as a Separate Clinical Entity: Insights from RNA Sequencing and Immunohistochemistry

Background: A molecular classification of endometrial cancer was developed based on an analysis of The Cancer Genome Atlas. In this classification, the group characterized by abnormal p53 immunohistochemical expression showed the poorest prognosis. However, there may be no need to apply a molecular classification in low-grade endometrial cancer. In this study, we investigated the clinical significance of abnormal p53 immunohistochemical expression in low-grade endometrial cancer. Methods: We obtained nine frozen samples of endometrial cancer [low-grade endometrial cancer with wild-type p53 expression (EClop53wt group): n = 3, low-grade endometrial cancer with abnormal p53 expression (EClop53ab group): n = 3, and high-grade endometrial cancer (EChi group): n = 3]. RNA sequencing was performed for each sample. All the samples passed RNA quality control. In addition, an immunohistochemical analysis was performed for 44 formalin-fixed paraffin-embedded samples. Results: Differentially expressed genes were identified in the RNA sequencing results (1811 genes between the EClop53ab group and the EChi group, and 1088 genes between the EClop53ab group and the EClop53wt group). In a principal component analysis, the EClop53ab group was more similar to the EClop53wt group than to the EChi group. In the immunohistochemical analysis, L1CAM expression was significantly less frequently observed in the EClop53ab group than in the EChi group. Moreover, p21 expression tended to be more frequently observed in the EClop53ab group than in the EChi group. Conclusions: In this study, the RNA sequencing and immunohistochemical results revealed that the EClop53ab group is a separate entity from the EChi group. While the abnormal p53 group is considered the most prognostically unfavorable in molecular classification, these findings suggest that routine molecular profiling is not necessary for patients with low-grade endometrial cancer. However, there is insufficient evidence to modify adjuvant treatment in low-grade endometrial cancer patients. Further investigation is needed on the clinical application of molecular classification to low-grade endometrial cancer.

POLE-Mutated Uterine Carcinosarcomas: A Clinicopathologic and Molecular Study of 11 Cases

Uterine carcinosarcomas (UCS) are high-grade biphasic neoplasms with generally poor outcomes. Based on The Cancer Genome Atlas molecular classification of endometrial carcinomas, the majority of UCS are classified as copy-number high/serous-like (p53-abnormal); however, a small subset represent other molecular subtypes, including those that harbor POLE mutations. We identified 11 POLE-mutated (POLEmut) UCS across 3 institutions and assessed the clinical, histopathologic, immunohistochemical, and molecular features of these tumors. POLEmut UCS occurred in adult women (median age, 64 years; range, 48-79 years) and usually presented as The International Federation of Gynecology and Obstetrics 2009 clinical stage IA (n = 4) or IB (n = 3). Almost all tumors were predominantly carcinomatous (n = 10), with most showing endometrioid morphology (n = 7), followed by ambiguous (n = 4) and serous (n = 3) histotypes. By immunohistochemistry, 7 tumors showed aberrant or subclonally aberrant expression of p53, 6 of which harbored pathogenic mutations in TP53 by sequencing. Other frequent mutations included PIK3CA (10/11), PTEN (8/11), RB1 (7/11), ARID1A (7/11), ATM (6/11), PIK3RA (5/11), and FBXW7 (4/11). Two tumors demonstrated loss of mismatch repair protein expression, and 1 had subclonal loss. Heterologous differentiation was uncommon, and only chondrosarcomatous type (n = 2) was observed. Mean and median follow-ups were 24.3 and 14.1 months, respectively (range, 1.4-61.1 months). Ten patients (91%) had no recurrences or death from disease, although 3 of these had follow-up periods <1 year. One patient, with the subclonal POLE variant, presented with stage IV disease and died 1.4 months after surgery. In conclusion, POLEmut UCS demonstrate unique morphologic and immunohistochemical features compared with their p53-abnormal counterparts and may have significant prognostic differences. Our study supports full molecular classification of UCS. We also raise awareness for potentially assessing POLE mutation allele frequency and clonality in consideration of classifying a tumor as POLEmut.

Comparison of PD-L1, VISTA, LAG-3, and GAL-3 Expressions and Their Relationships to Mismatch Repair Protein and p53 Expression in 529 Cases of Endometrial Carcinoma

The aim of this study is to evaluate the expressions of programmed death-ligand 1 (PD-L1), V-domain Ig suppressor of T-cell activation (VISTA), lymphocyte activation gene-3 (LAG-3), and galectin-3 (GAL-3), in mismatch repair-deficient (MMRd)/MMR-proficient and abnormal p53 expressing endometrial carcinomas and their relationship with clinical-histopathological features. Patients who underwent surgery for endometrial carcinoma between January 2008 and December 2018 were included in the study. Immunohistochemical analysis of MLH1, PMS2, MSH2, MSH6, p53, PD-L1, VISTA, LAG-3, and GAL-3 was performed on the tissue samples of microarray. A total of 529 patients were included. MMRd and p53-mutant tumors accounted for 31.5% and 11.5% of cases, respectively. PD-L1 and LAG-3 expressions in the MMRd and p53-mutant groups were higher than in the MMR-proficient group ( P < 0.001). GAL-3 expression in the MMR-proficient group was statistically higher than in the MMRd and p53-mutant groups ( P < 0.001). Mean age, grade, International Federation of Gynecology and Obstetrics stage, lymphovascular invasion, and lymph node metastasis were significantly higher in the p53-mutant group ( P < 0.001). In the group with PD-L1 expression, nonendometrioid histologic type, tumor grade, and lymphovascular invasion were significantly higher ( P < 0.001). Tumor grade, lymphovascular invasion, lymph node metastasis, and microcystic, elongated and fragmented pattern of invasion were significantly higher in the group with high VISTA expression ( P < 0.05). Tumor grade was significantly higher in the group with LAG-3 expression ( P < 0.001). Immunohistochemically determined subgroups and PD-L1, VISTA, LAG-3, and GAL-3 expression levels may be useful indicators of molecular features, and clinical outcomes also may have important implications for the development of targeted therapies in endometrial carcinoma.

Neoadjuvant Immunotherapy for Patients With Microsatellite Instability-High or POLE-Mutated Locally Advanced Colorectal Cancer With Bulky Tumors: New Optimization Strategy

OBJECTIVE

To evaluate the efficacy and safety of neoadjuvant immunotherapy for patients with microsatellite instability-high (MSI-H) or DNA polymerase ε (POLE)-mutated locally advanced colorectal cancer (LACRC) with bulky tumors.  PATIENTS: We retrospectively reviewed 22 consecutive patients with MSI-H or POLE-mutated LACRC with bulky tumors (>8 cm in diameter) who received preoperative programmed death-1 blockade, with or without CapOx chemotherapy.  MAIN OUTCOME MEASURES: Pathological complete response (pCR), clinical complete response (cCR), toxicity, R0 resection rate, and complications were evaluated. Survival outcomes were analyzed using the Kaplan-Meier method. Multiplex immunofluorescence analysis were performed before and after treatment.  RESULTS: The incidence of immune-related adverse events (irAEs) was 36.4% (8/22). Five of 22 patients presented with surgical emergencies, most commonly perforation or obstruction. The 22 patients underwent a median 4 (1-8) cycles. Two patients were evaluated as cCR and underwent a watch and wait strategy. The R0 resection rate was 100.0% (20/20) and pCR rate was 70.0% (14/20). Twelve of 14 cT4b patients (85.7%) avoided multivisceral resection, and 10 of them achieved pCR or cCR. In the two patients with POLE mutations, one each achieved pCR and cCR. No Grade III/IV postoperative complications occurred. The median follow-up was 16.0 months. Two-year event-free and overall survival for the whole cohort was both 100%.  CONCLUSIONS: Preoperative immunotherapy is the optimal option for MSI-H or POLE-mutated LACRC with bulky tumors, especially cT4b. Preoperative immunotherapy in patients with T4b CRC can reduce multivisceral resection and achieve high CR rate.

Initiation of molecular testing of endometrial carcinomas in a population-based setting: practical considerations and pitfalls

AIMS

Since the publication of The Cancer Genome Atlas (TCGA) molecular Classification of endometrial carcinomas in 2013, multiple studies have demonstrated the prognostic and therapeutic importance of this. However, there is great variability on whether and how this is undertaken in different institutions, and this is often dependent on resources and availability of molecular testing. Points of controversy include whether molecular classification is needed on all endometrial carcinomas and whether pure molecular testing is undertaken or a surrogate such as the ProMisE (Proactive Molecular Risk Classifier for Endometrial Cancer) Classifier. Herein we report our experience instigating molecular classification of endometrial carcinomas in Northern Ireland.

METHODS AND RESULTS

From 1st March 2023, all endometrial carcinomas diagnosed on biopsy in the four pathology laboratories in Northern Ireland were referred to the central molecular pathology laboratory for genomic analysis using a custom next-generation sequencing (NGS) panel; the NGS panel included the entire coding regions of polymerase epsilon (POLE) and TP53 genes, as well as microsatellite instability (MSI) analysis. All cases also underwent immunohistochemical staining with oestrogen receptor (ER), p53, and the mismatch repair (MMR) proteins MLH1, PMS2, MSH2, and MSH6. The molecular results were available by the time of surgery (if a hysterectomy was performed) allowing integration into the final pathology report where a TCGA molecular type was assigned. Two hundred and sixty-seven endometrial carcinomas underwent molecular testing; in five cases, there was insufficient material for testing, leaving 262 cases. The TCGA groups were POLEmut (19; 7.3%), MMRd (63; 24%), p53abn (62; 23.7%), and no specific molecular profile (NSMP) 118 (45%). Seventeen tumours (6.5%) were "multiple-classifiers": five POLEmut-p53abn, two POLEmut-MMRd, one POLE-MMRd-p53abn (all included in the POLEmut TCGA group), and nine MMRd-p53abn (included in the MMRd group).

CONCLUSION

This represents one of the first population-based studies investigating the prevalence of the different TCGA molecular groups of endometrial carcinomas in an unselected population. Performing molecular testing on biopsies enables management to be tailored to the molecular group and allows integration of the TCGA group into the report of the final resection specimen. We hope our experience will facilitate other laboratories in undertaking TCGA molecular classification.

Molecular Classification of Endometrial Cancers Using an Integrative DNA Sequencing Panel

BACKGROUND AND OBJECTIVES

Adoption of molecular classification in endometrial cancer (EC) into clinical practice remains challenging due to complexity in coordination of multiple assays. We aimed to develop a simple molecular technique to classify ECs into four subgroups using our custom-designed targeted sequencing panel.

METHODS

Patients with newly diagnosed ECs were prospectively recruited from three cancer centres in Ontario, Canada. Using our panel, 181 ECs were sequenced. Variants were analysed for pathogenicity and clinicopathologic information was collected through medical records retrospectively.

RESULTS

Of 181, 86 (48%) were mismatch repair deficient (MMRd), of which 62 (72%) harboured MLH1 promoter methylation and 24 (28%) had pathogenic variants in MMR genes. Of single classifiers, three (1.8%) had pathogenic POLE (POLEmut), 15 (9%) had TP53 mutations (p53abn) and 61 (37%) had no specific molecular profile subtype (NSMP). Sixteen (9%) had more than one molecular classifying feature, with eight (4%) MMRd-p53abn, six (3%) POLEmut-MMRd, one (0.5%) POLEmut-MMRd-p53abn and one (0.5%) POLEmut-p53abn. When MMRd group was further subclassified according to mechanism of MMR loss, MLH1 promoter methylated group had worse outcomes than those with somatic MMR pathogenic variants.

CONCLUSIONS

Our panel can classify ECs into four subgroups through a simplified process and can be implemented reflexively in clinical practice.

Molecular characterization of mixed-histology endometrial carcinoma provides prognostic and therapeutic value over morphologic findings

We performed molecular analysis of a single-institution cohort of clinically diagnosed mixed-histology endometrial carcinoma (MEC). A gynecologic pathologist confirmed that 72 cases met diagnostic criteria for MEC based on WHO 2020 guidelines, and these were molecularly classified using both a DNA-based and histologic approach. Tumors were classified as: POLE-mutated (13.9%), microsatellite instability (MSI)-high/mismatch repair deficient (MMRd) (26.4%), TP53/p53 abnormal (p53abnl) (48.6%), no specific molecular profile (NSMP) (11.1%). Recurrence risk significantly differed based upon molecular class, but not histology. 44% of MEC cases had a HER2 IHC score of 2-3+, and this was not limited to p53abnl tumors. Transcriptional analysis demonstrated 93 differentially expressed genes between p53abnl and NSMP tumors, including many associated with the innate immune response and DNA damage repair. While p53abnl and NSMP tumors have similarly poor outcomes, transcriptome analysis revealed biologic differences that could impact targeted therapeutics in this high-risk group.

The impact of integrated genomic analysis on molecular classifications and prognostic risk stratification in endometrial cancer: a Chinese experience

Background

The molecular classification of endometrial cancer (EC), as proposed by The Cancer Genome Atlas (TCGA), has transformed tumor classification, but there is a lack of extensive research on the molecular profiles and subtyping of endometrial cancer patients in China.

Methods

200 EC patients were classified into the following four molecular types: (i) POLEmut; (ii) MSI-H; (iii) TP53mut; (iv) NSMP. This study aimed to investigate the molecular characteristics of EC patients at a single center by large-scale next generation sequencing(NGS), including clinicopathological features and gene mutations in patients with distinct molecular types, and to assess the relevance of molecular subtyping for postoperative adjuvant therapy.

Results

NSMP group was the most prevalent, comprising 46.0% (92/200) of cases, followed by the TP53mut group at 17.5% (35/200), the MSI-H group at 23.5% (47/200), and the POLEmut group at 13.0% (26/200). CTNNB1 mutations were common in the POLEmut group but rare in the TP53mut group. With the application of the new European Society for Medical Oncology (ESMO) 2022 classification, 27 patients (14.1%) were reclassified. Concordance between the two classifications regarding postoperative risk was observed in 85.9% (165/192) of cases. Seven patients (3.6%) were downstaged, and twenty patients (10.4%) were upgraded. Additionally, the analysis revealed that eleven genes were significantly mutated in patients with lymphovascular space invasion (LVSI) compared to those without LVSI. Notably, NSD3 and POLD1 were highly mutated in patients with lymphatic metastasis compared to those without lymphatic metastasis. Conclusively, large-scale NGS has revolutionized EC management by facilitating rapid molecular subtype identification, guiding tailored adjuvant therapies, targeted treatments, and immunotherapies, and efficiently screening for Lynch syndrome, thereby significantly improving patient outcomes.

Molecular classification of endometrial cancers (EC) and association with relapse-free survival (RFS) and overall survival (OS) outcomes: Ancillary analysis of GOG-0258

PURPOSE

Determine if molecular classification using mismatch repair (MMR) and p53 protein expression predicts recurrence-free survival (RFS) and overall survival (OS) in endometrial cancer (EC) patients treated with chemotherapy and radiation (CRT) versus chemotherapy (CT).

METHODS

GOG-0258, a phase III randomized trial (NCT00942357), compared CRT to CT. Immunohistochemistry assessed MMR and p53 status. Kaplan-Meier curves and adjusted Cox models analyzed survival outcomes by molecular subtype.

RESULTS

ECs classified as deficient MMR (dMMR) (27 %), p53 abnormal (p53abn) (24 %), and p53 wild type (p53wt) (49 %). p53abn were more frequent in patients that were older, Black, and had serous histology (p < 0.001). Median follow up was 113 months. Five-year RFS and OS were worse with p53abn (29 % [Hazard Ratio (HR) = 3.39 (95 % Confidence Interval (CI): 2.34-4.91)] and 39 % [HR = 4.64 (95 % CI: 3.16-6.79)] compared to those with p53wt (referent) (p < 0.001). The five-year RFS and OS for dMMR cancers were (58 % [HR = 1.30 (95 % CI: 0.85-1.97)] and 77 % [HR = 1.53 (95 % CI: 0.99-2.36)] compared to those with p53wt (69 % and 85 %). After adjusting for age, gross residual disease, and treatment, p53wt improved RFS with CRT compared to CT in an exploratory analysis (77 % vs 60 %; HR = 0.54 (95 % CI: 0.32-0.94). The 5-year and 10-year OS rates were similar in CRT compared to CT in all subgroups.

CONCLUSION

Molecular classification appears to be predictive and prognostic, with worse survival in those with p53abn tumors. In an exploratory analysis, p53wt appears to predict improved RFS, favoring CRT over CT. There was no difference in treatment efficacy based on molecular subtype for OS.

A fully next-generation sequencing-based method of classifying molecular sub-types of endometrial cancer retains prognostic value and expands biomarker targets

OBJECTIVE

The molecular classification of endometrial cancer into POLE-ultra-mutated, mismatch repair-deficient, p53-mutated, and no specific molecular profile sub-types has significant prognostic value and is recommended in the evaluation of all patients with endometrial cancer. Nonetheless, there has been inconsistent clinical implementation. One possible barrier is the current practice of using several different assays, each with its own result, that subsequently need to be integrated. We developed a single, fully next-generation sequencing (NGS)-based assay that sub-types endometrial samples and evaluated it against an existing algorithm.

METHODS

Molecular sub-typing was retrospectively performed on 142 formalin-fixed, paraffin-embedded endometrial cancer samples using a clinically validated NGS panel targeting 133 genes and additional loci for micro-satellite instability and tumor mutational burden. In parallel, these same samples were classified by the World Health Organization algorithm using mismatch repair and p53 immunohistochemistry, and POLE sequencing. Concordance between algorithms was assessed, and the prognostic value of each was evaluated. We further explored racial disparities in outcomes and assessed other prognostic and potentially therapeutic biomarkers.

RESULTS

The sequencing-based method was highly concordant with the World Health Organization algorithm (136/142 patients, Cohen's κ = 0.94) and retained prognostic value, with a significant difference in overall survival and progression-free survival by sub-type, and similar stratification to that initially identified in The Cancer Genome Atlas analysis. In addition, 11 cases had sequence variants in the previously established prognostic biomarker CTNNB1, and 3 cases had potentially targetable sequence variants in ERBB2. Endometrial cancer outcomes in Black individuals were worse, in part owing to the increased incidence of sub-types with a poor prognosis.

CONCLUSIONS

A fully sequencing-based assay streamlines molecular classification of endometrial cancer and retains the prognostic value of other validated methods, which may aid clinical implementation. The additional genomic information obtained with an NGS panel, beyond the classification markers, can broaden potentially applicable therapies.

POLE mutations in endometrial carcinoma: Clinical and genomic landscape from a large prospective single-center cohort

BACKGROUND

To date, 11 DNA polymerase epsilon (POLE) pathogenic variants have been declared "hotspot" mutations. Patients with endometrial cancer (EC) characterized by POLE hotspot mutations (POLEmut) have exceptional survival outcomes. Whereas international guidelines encourage deescalation of adjuvant treatment in early-stage POLEmut EC, data regarding safety in POLEmut patients with unfavorable characteristics are still under investigation. On the other hand, the spread of comprehensive genome profiling programs has underscored the need to interpret POLE variants not considered to be hotspots.

METHODS

This study provides a comprehensive analysis of 596 sequenced patients with EC. The genomic landscape of POLEmut EC was compared with cases harboring nonhotspot POLE mutations within the exonuclease domain. Additionally, the genomic characteristics of multiple classifiers, as well as those exhibiting unfavorable histopathological and clinical features, were examined.

RESULTS

No significant genomic differences were observed among patients with POLEmut EC when comparing multiple classifiers to not-multiple classifiers or those with unfavorable clinical features. However, the tumor mutational burden differed in both comparisons, whereas the percentage of C>G mutations only differed in the comparison based on clinical features. Specific POLE mutations, even if not considered to be hotspots, have genomic features comparable to POLEmut.

CONCLUSIONS

The present findings confirm the absence of significant genomic differences among POLEmut patients regardless of multiple-classifier status or association with high-risk clinical features. Prognostic data will be essential to elucidate the clinical significance of POLE mutations not classified as hotspots that exhibit genomic characteristics similar to those in POLEmut patients.

Added prognostic value of sentinel lymph node mapping in endometrial cancer to molecular subgroups

OBJECTIVE

Treatment approaches for endometrial cancer became more personalized in the last decade, mainly due to two key advancements - sentinel lymph node (SLN) mapping and molecular classification. However, their prognostic interaction remains relatively unexplored.

METHODS

This retrospective cohort study included patients with endometrial cancer, who underwent surgical treatment including SLN mapping at the Bern University Hospital, Switzerland. Ultrastaging of the SLNs and a molecular analysis on the primary tumor was performed.

RESULTS

The study cohort included 206 patients, of which 197 tumor samples underwent molecular classification. 11.2 % were classified as POLEmut, 25.9 % as MMRd, 46.2 % as NSMP, and 16.8 % as p53abn. Overall, 834 SLN were removed. SLN macrometastasis were most prevalent in patients with p53abn tumors (24.2 %), followed by MMRd (13.7 %), NSMP (5.5 %), and POLEmut (0 %) tumors (p = .006). Mean follow-up time was 70.9 months. SLN macrometastasis was significantly associated with a higher risk of recurrence in the entire study cohort (p > .001) and the NSMP subgroup (p > .001). In the MMRd subgroup, SLN macrometastasis remained a significant predictor of recurrence (p = .030) and disease-specific death (p = .047) in multivariate Cox regression analysis. For patients with p53abn endometrial cancer, there was no association between SLN macrometastasis and risk of recurrence (p = .618) or disease specific death (p = .798).

CONCLUSIONS

SLN macrometastasis is an independent predictor of recurrence and disease-specific death in patients with MMRd endometrial cancer. In the subgroup of p53abn endometrial cancers, SLN macrometastasis did not have an added impact on oncological outcome.

Cervical stromal invasion and molecular characterization in stage II-IV endometrial cancers

OBJECTIVE

The optimal treatment for patients with cervical stromal invasion (CSI) in endometrial cancer (EC) remains unclear. We aimed to test the prognostic role of molecular classification in EC patients with CSI.

METHODS

A retrospective, multicenter review of EC patients with CSI was performed. EC cases were assigned to one of the molecular classes: POLE mutated (POLEmut), MMR deficient (MMRd), p53 abnormal (p53abn), or no specific molecular profile (NSMP). Three-year recurrence-free survival (RFS) from surgery was estimated using the Kaplan-Meier method. Cox proportional hazards regression models were fit to adjust for confounders.

RESULTS

Overall, 162 EC patients with CSI were identified: 70 (43.2 %) NSMP, 49 (30.2 %) p53abn, 40 (24.7 %) MMRd, 3 (1.9 %) POLEmut. POLEmut cases were excluded from further analysis, because of the small number of patients identified. At univariate analysis, molecular class was significantly associated with recurrence within 3 years after surgery (p = 0.04). Three-year RFS was 59.9 % (95 % confidence interval [CI], 46.1-77.8 %) for NSMP, 50.6 % (95 % CI, 34.9-73.2 %) for MMRd, and 33.1 % (95 % CI, 19.7-55.3 %) for p53abn. After adjusting for stage and grade, molecular class was no longer significantly associated with recurrence within three years (p = 0.28).

CONCLUSIONS

Traditional risk factors such as grade and stage remain critical in determining the prognosis of endometrial cancer with cervical stromal invasion. This study highlights the importance of integrating both molecular and morphological features in determining the prognosis of endometrial cancer, with particular emphasis on endometrioid histotypes.

Molecular Classification of Endometrial Carcinoma: Insights From a Teaching Hospital

ABSTRACT

Endometrial carcinoma is a heterogeneous disease with distinct molecular subtypes that have varied prognosis and therapeutic implications. Since the development of molecular signatures of malignancy is prominent, we are trying to implement this development in our cases of previously diagnosed endometrial cancer. The aim was to determine the prevalence of specific molecular alterations and correlate the genetic profile with the pathologic features and clinical characteristics. We identified 100 cases of endometrial carcinoma, which were eventually classified using immunostains for mismatch repair (MMR) and p53 proteins, in addition to Sanger analysis for POLE gene (Ex, 9, 13, 14). Our findings showed a high prevalence of nonspecific molecular profile (NSMP) in 46 cases (46%), and MMR deficiency in 30 cases (30%). The worst prognosis was observed in the p53 mutant pattern expressed tumors. No statistical difference in pathologic characteristics was observed when the molecular classification was applied. Of note, mutual molecular grouping assignment appears to be present in 5 (5%) of cases of endometrial carcinoma. This is the first study conducted in Saudi Arabia that investigated the prevalence and implications of these molecular subtypes in endometrial carcinoma. The percentage of cases in our result is similar to what had been published globally.

Meta-analysis of the clinicopathologic features of endometrial cancer molecular staging

Objective

The 2013 TCGA identified four molecular subgroups of endometrial cancer; however, the data results for most of the pathological features were varied and of low value for clinical application. Therefore, a meta-analysis of articles related to the clinicopathological features of molecular typing was performed to observe how the prevalence of the four subgroups varied across different pathological features and whether they were associated with certain specific pathological features and to understand how molecular typing may influence current pathological assessments.

Methods

PubMed, Embase, Web of Science, CNKI, Wanfang, and VIP were searched from the time of library construction until May 2024, and the following data were extracted: histological type, FIGO grade, FIGO stage, LVSI, depth of muscularis propria infiltration, and lymph node status of each TCGA group. Two reviewers used the Cochrane Diagnostic Research Scale assessment, and the data were analyzed using Review Manager 5.4.1 and Stata 14.0.

Results

Fourteen diagnostic research papers were included in this study, with a total of 4,776 patients with endometrial cancer. Non-estrogen-related endometrial carcinoma (NEEC) vs. estrogen-related endometrial carcinoma (EEC) was low in polymerase epsilon (POLE) (OR = 0.49), microsatellite instability (MSI) (OR = 0.45), and copy number low (CNL) (OR = 0.11), while it was high in CNH (OR = 26.76). G3 EEC vs. G1-2 EEC POLE (OR = 1.98), MSI (OR = 1.74), and CNH (OR = 5.57) were high, whereas it was low in CNL (OR = 0.23), low in FIGO II-IV vs. FIGO I in POLE (OR = 0.39) and CNH (OR = 0.64), and high in FIGO II-IV vs. FIGO I in CNH (OR = 3.05). There was no difference in MSI prevalence in FIGO II-IV vs. FIGO I. POLE (OR = 0.64) and CNL (OR = 0.75) were low in myometrial invasion depths ≥50% and lower in myometrial invasion depths <50%, and CNL (OR) was higher in CNH (OR) than in myometrial invasion depths <50%. There was no difference in MSI between different myometrial invasion depths. MSI (OR = 1.69) and CNH (OR = 2.12) were higher in lymphatic vascular infiltration (LVSI) vs. no LVSI; CNL (OR = 0.39) was lower in LVSI than in no LVSI. There was no difference in POLE in the presence or absence of LVSI. Lymph node metastasis with and without lymph node metastasis in POLE (OR = 0.25) and CNL (OR = 0.31) were lower, and CNH (OR = 3.06) was higher in lymph node metastasis than in no lymph node metastasis. There was no difference in MSI in the presence or absence of lymph node metastasis.

Conclusions

POLE patients predominated in pathological features of early-stage endometrial cancer and had better prognosis. MSI patients were more likely to be found in EEC and G3 EEC as well as LVSI. Nearly half of G3 EEC as well as LVSI were present in MSI patients, and CNH patients were more likely to be found to have pathological features of advanced endometrial cancer and poor prognosis, providing evidence that CNH is a high-risk cancer. Patients with CNL were more likely to be found to have pathological features of early-stage endometrial cancer and good prognosis, and CNL was present in large numbers in both early-stage and late-stage endometrial cancers. CNL does not yet have a precise prognostic value.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42024563661.

Hormonal biomarkers remain prognostically relevant within the molecular subgroups in endometrial cancer

OBJECTIVE

The prognostic relevance of hormonal biomarkers in endometrial cancer (EC) has been well-established. A refined three-tiered risk model for estrogen receptor (ER)/progesterone receptor (PR) expression was shown to improve prognostication. This has not been evaluated in relation to the molecular subgroups. This study aimed to evaluate the ER/PR expression within the molecular subgroups in EC.

METHODS

A retrospective multicenter cohort study was performed and data from the European Network for Individualized Treatment centers and Vancouver, Canada were used. ER/PR immunohistochemical expression was grouped as: ER/PR 0-10 %, 20-80 % or 90-100 %. Molecular subgroups were determined with full next-generation sequencing or combined with immunohistochemistry: POLEmut, mismatch repair deficient (MMRd), p53mut and no-specific molecular profile (NSMP).

RESULTS

A total of 739 patients were included (median follow-up 5.0 years). Tumors were classified as POLEmut in 9.1 %(N = 67), MMRd in 27.6 %(N = 204), p53mut in 20.8 %(N = 154) and NSMP in 42.5 %(N = 314). Among all molecular subgroups, patients with ER/PR 90-100 % expression revealed the best disease-specific survival (DSS). Within p53mut, PR 90-100 % expression showed a 5-year DSS of 100.0 %. ER expression is prognostic more relevant in MMRd and NSMP tumors while PR expression in p53mut and NSMP tumors. Across all molecular subgroups, PR 0-10 %, p53mut, lympho-vascular space invasion and FIGO stage III-IV remained independently prognostic for reduced DSS Whereas PR 90-100 % and POLEmut remained independently prognostic for improved DSS.

CONCLUSION

We demonstrated that ER/PR expression remain prognostically relevant within the molecular subgroups, and that a three-tiered cutoff refines prognostication. These data support incorporating routine evaluation of ER/PR expression in clinical practice.

The prognostic impact of molecular classification in endometrial cancer that undergoes fertility-sparing treatment

OBJECTIVE

No biomarkers are available to predict treatment response in patients with endometrial cancers who undergo fertility-sparing treatment. Therefore, we aimed to evaluate the prognostic role of molecular classification.

METHODS

Patients with endometrial cancer who underwent fertility-sparing treatment with progestins between 2005 and 2021 were retrospectively identified. Polymerase epsilon (POLE), TP53/p53, and mismatch repair (MMR) proteins were assessed to assign patients to molecular groups: POLE mutated (POLEmut), MMR deficient (MMRd), no specific molecular profile (NSMP), and p53 abnormal (p53abn). Treatment response was classified as complete, partial, stable disease, or progressive. Response at 6 months, best response, and recurrence after complete response were evaluated by molecular class.

RESULTS

In total, 33 patients were assigned to a molecular class and included in the analysis. Molecular testing detected 3 POLEmut (9%), 3 MMRd (9%), 25 NSMP (76%), and 2 p53abn (6%); 0 of 3 POLEmut (0%), 0 of 3 MMRd (0%), 6 of 25 NSMP (24%), and 1 of 2 p53abn (50%) achieved complete response within 6 months. In terms of best response during the entire treatment period, 2 of 3 POLEmut (67%), 2 of 3 MMRd (67%), 18 of 25 NSMP (72%), and 1 of 2 p53abn (50%) showed complete response. After complete response was achieved, 1 of 2 POLEmut (50%), 2 of 2 MMRd (100%), 14 of 18 NSMP (78%), and 0 of 1 p53abn (0%) had a recurrence.

CONCLUSION

Although the small number of patients limits our findings, a lower proportion of MMRd responded to progestins than of NSMP.

Clinicopathologic stratification demonstrates survival differences between endometrial carcinomas with mismatch repair deficiency and no specific molecular profile: a cohort study

OBJECTIVE

Endometrial carcinomas with mismatch repair deficiency (MMRd) and no specific molecular profile (NSMP) are considered to have intermediate prognoses. However, potential prognostic differences between these molecular subgroups remain unclear due to the lack of standardized control for clinicopathologic factors. This study aims to evaluate outcomes of MMRd and NSMP endometrial carcinomas across guideline-based clinicopathologic risk groups.

METHODS

This study analyzed patients treated at a single tertiary center. Immunohistochemistry and polymerase-ϵ sequencing were performed for molecular classification. MLH1-deficient tumors underwent methylation-specific multiplex ligation-dependent probe amplification. Carcinomas were classified into clinicopathologic risk groups according to European guidelines.

RESULTS

The analysis included 420 MMRd and 399 NSMP carcinomas. Among MMRd cases, 224 were subcategorized as MLH1-methylated or MLH1-non-methylated. Median follow-up was 71 months (range; 1-136). Survival differences were most notable in clinicopathologic medium-risk carcinomas, with the MMRd subgroup exhibiting poorer progression-free, disease-specific, and overall survival compared to NSMP. Adjusting for age and adjuvant therapy, MMRd still showed an association with progression-free survival. Both MLH1-methylated (n = 154) and MLH1-non-methylated tumors (n = 70) were associated with more aggressive clinicopathologic risk groups compared to NSMP, but only methylated tumors showed poorer outcomes.

CONCLUSION

The distinct outcomes for MMRd and NSMP in the clinicopathologic medium-risk group suggest that uterine risk factors may worsen the prognosis for MMRd endometrial carcinomas. Advanced stage may be the primary factor contributing to poor outcomes in high-risk-advanced metastatic carcinomas. Clinicopathologic factors may particularly worsen the prognosis of MLH1-methylated carcinomas.

Abnormal p53 High-Grade Endometrioid Endometrial Cancer: A Systematic Review and Meta-Analysis

OBJECTIVE

Our primary objective was to evaluate the oncologic outcomes of patients with abnormal p53 FIGO grade 3 (high-grade) endometrioid endometrial cancer. As secondary objectives, we determined the global prevalence of abnormal p53 in grade 3 endometrioid endometrial carcinomas and the geographical variations.

METHODS

The following electronic databases were searched: PubMed/Medline, EMBASE, Cochrane Library, Scopus, and Web of Science. We followed the Meta-Analysis for Observational Studies in Epidemiology guidelines and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. This review was preregistered with PROSPERO (no: CRD42023495192). Bias was assessed using the Quality in Prognosis Studies tool. For time-to-event data, the effect of p53 status on grade 3 endometrial cancer was described using hazard ratios (HRs) and corresponding 95% confidence intervals (CIs). Overall survival and progression-free survival were analyzed using one- and two-stage approaches, the Kaplan-Meier method, and Cox proportional hazards models.

RESULTS

Fifty-seven studies with 2528 patients were included. Patients with abnormal p53 had an increased risk of death (HR, 1.29 (95% CI, 1.11-1.48); I2 = 88%) and disease progression (HR, 1.63; 95% CI, 1.42-1.88; I2 = 2%) compared with patients with wildtype p53 G3 endometrial cancer. The global pooled prevalence of abnormal p53 was 30% (95% CI, 25-34%; tau2 = 0.02; I2 = 74%), with the highest prevalence being found in studies conducted in Asia (95% CI, 27-41%; tau2 = 0.01; I2 = 52%).

CONCLUSIONS

Abnormal p53 grade 3 endometrioid endometrial cancer is more common in Asia, and it is associated with decreased overall survival and progression-free survival.

Next-generation sequencing in the molecular classification of endometrial carcinomas: Experience with 270 cases suggesting a potentially more aggressive clinical behavior of multiple classifier endometrial carcinomas

Molecular classification of endometrial carcinomas (EC) divides these neoplasms into four distinct subgroups based on their molecular background. Given its clinical significance, genetic examination is becoming integral to the diagnostic process. This study aims to share our experience with the molecular classification of EC using immunohistochemistry (IHC) and next-generation sequencing (NGS). We included all ECs diagnosed at two institutions from 2020 to the present. All cases were prospectively examined by IHC for MMR proteins and p53, followed by NGS using a customized panel covering 18 genes, based on which ECs were classified into four molecular subgroups: POLE mutated, hypermutated (MMR deficient), no specific molecular profile (NSMP), and TP53 mutated. The cohort comprised 270 molecularly classified ECs: 18 (6.6%) POLE mutated, 85 (31.5%) hypermutated, 137 (50.7%) NSMP, and 30 (11.1%) TP53 mutated. Twelve cases (4.4%) were classified as 'multiple classifier' EC. Notably, most of these cases with available follow-up (6/9) behaved aggressively. Within the POLEmut EC group, 3/4 cases had advanced tumors, including one patient who died of the disease. Similarly, in the MMRd/TP53mut group, 3/5 patients with available follow-up had metastatic disease, leading to death of the patient in 1 case. ECs of NSMP showed multiple genetic alterations, with the most common mutations being PTEN (44% within the group of NSMP), followed by PIK3CA (30%), ARID1A (21%), and KRAS (9%). Our findings suggest that combining immunohistochemistry with NGS offers a more reliable classification of ECs, including 'multiple classifier' cases, which, based on our observations, tend to exhibit aggressive behavior. Additionally, our data highlight the complex genetic background of NSMP ECs, which can facilitate further stratification of tumors within this group and potentially help select patients for dedicated clinical trials.

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

OBJECTIVES

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.

METHODS

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 POLE status, immunohistochemistry for mismatch repair and p53) with ProMisE NGS (NGS for POLE and TP53, microsatellite instability assay) for concordance metrics and Kaplan-Meier survival statistics across molecular subtypes. In parallel, we assessed all patients who had undergone a new NGS based molecular classification test (n=334) comparing molecular subtype assignment with the original ProMisE classifier.

RESULTS

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.

CONCLUSION

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.

Less is more? Comparison between genomic profiling and immunohistochemistry-based models in endometrial cancer molecular classification: A multicenter, retrospective, propensity-matched survival analysis

BACKGROUND

Genomic profiling-based model (GP-M) is the gold-standard for endometrial cancer (EC) molecular classification, but several issues related to the availability of genomic sequencing in low-income settings remain and health disparities in the management are increasing. This study aims to investigate the non-inferiority of the immunohistochemistry-alone model in classifying ECs compared to the standard genomic profiling-based model in terms of oncologic outcomes.

METHODS

All preoperative uterine-confined ECs undergoing surgical staging were retrospectively included. Patients classified by IHC-M were stratified into: MMR-proficient (MMRp), p53 wild type (p53wt) and estrogen receptor (ER) positive, 2) MMRp, p53wt and ER-negative, 3) MMRd, and 4) p53abn. A case-control comparison was performed between the IHC-M and GP-M cohorts. Then, a propensity-matched analysis was performed: ECs classified by IHC-M were matched in a 3:1 ratio with patients classified by GP-M.

RESULTS

1587 patients with EC were included. The Kaplan-Meier survival curves for disease-free survival and overall survival demonstrated that the two models performed similarly in risk-stratifying the study population (p < 0.0001). Moreover, the AUC-ROC showed overlapping results: 0.77 (0.66-0.87) for IHC-M and 0.72 (0.63-0.81) for GP-M, indicating that both models were able to successfully identify patients at high-risk and low-risk of disease recurrence/progression.

CONCLUSION

The IHC-M showed overlapping classification performance compared to the GP-M in terms of oncologic outcomes. This study may lay the basis to further investigate the real-life clinical impact of POLE sequencing in molecular classification and the potential stand-alone prognostic role of ER status for further allocation of EC patients into risk classes.

Co-reactivity pattern of glucose metabolism and blood perfusion revealing DNA mismatch repair deficiency based on PET/DCE-MRI in endometrial cancer

BACKGROUND

Identifying DNA mismatch repair deficiency (MMRd) is important for prognosis risk stratification in patients with early-stage endometrial cancer (EC), but there is a notable absence of cost-effective and non-invasive preoperative assessment techniques. The study explored the co-reactivity pattern of glucose metabolism and blood perfusion in EC based on hybrid [18F]fluorodeoxyglucose ([18F]FDG) PET/dynamic contrast enhanced (DCE)-MRI to provide an imaging biomarker for identifying MMRd.

METHODS

Patients with a history of postmenopausal bleeding and initially diagnosed with EC on ultrasound were recruited to perform a PET/DCE-MRI scan. Glucose metabolism parameters were calculated on PET, and blood perfusion parameters were calculated semi-automatically by the DCE-Tofts pharmacokinetic model. The MMRd of early-stage EC was evaluated by immunohistochemistry. The synchronous variation of PET and DCE-MRI parameters was compared between the MMRd and mismatch repair proficiency (MMRp). The association between PET/DCE-MRI and MMRd was analyzed by logistic regression to establish the digital biomarker for predicting MMRd. Receiver operating characteristic curve, decision curve analysis, and the net reclassification index (NRI) were used to evaluate the value of the digital biomarker in identifying MMRd.

RESULTS

Eighty-six early-stage EC cases (58.92 ± 10.13 years old, 34 MMRd) were enrolled. The max/mean standardized uptake value (SUVmax/SUVmean), metabolic tumor volume, total lesion glycolysis, transfer constant (Ktrans), and efflux rate (Kep) were higher in MMRd than those in MMRp (P < 0.001, < 0.001, 0.002, 0.004, < 0.001, and 0.005, respectively). The correlations between glucose metabolism and blood perfusion were different between the MMRd and MMRp subgroups. SUVmax was correlated with Kep (r = 0.36) in the MMRd. SUVmean (odds ratio [OR] = 1.32, P = 0.006) and Ktrans (OR = 1.90, P = 0.021) were independent risk factors for MMRd. And the digital biomarker that combined SUVmean and Ktrans outperformed in identifying MMRd in early-stage EC more than DCE-MRI (AUC: 0.83 vs. 0.78, NRI = 13%).

CONCLUSION

A potential digital biomarker based on [18F]FDG PET/DCE-MRI can identify MMRd for prognosis risk stratification in early-stage EC.

Advances in Immunotherapy for Endometrial Cancer: Insights into MMR Status and Tumor Microenvironment

Endometrial cancer is one of the most common gynecological malignancies, and while early-stage cases are highly treatable, recurrent or advanced EC remains challenging to manage. Immunotherapy, particularly immune checkpoint inhibitors, has revolutionized treatment approaches in oncology, and its application in EC has shown promising results. Key to immunotherapy efficacy in EC is the tumor's mismatch repair status, with MMR-deficient tumors demonstrating a higher tumor mutational burden and increased PD-L1 expression, making them more susceptible to immune checkpoint inhibitors (ICIs) such as pembrolizumab, durvalumab, and dostarlimab. However, not all mismatch repair-deficient (MMRd) tumors respond to ICIs, particularly those with a "cold" tumor microenvironment (TME) characterized by poor immune infiltration. In contrast, some MMR-proficient tumors with a "hot" TME respond well to ICIs, underscoring the complex interplay between MMR status, tumor mutational burden (TMB), and TME. To overcome resistance in cold tumors, novel therapies, including Chimeric Antigen Receptor (CAR) T cells and tumor-infiltrating lymphocytes are being explored, offering targeted immune-based strategies to enhance treatment efficacy. This review discusses the current understanding of immunotherapy in EC, emphasizing the prognostic and therapeutic implications of MMR status, TME composition, and emerging cell-based therapies.

A nomogram model to predict recurrence of early-onset endometrial cancer after resection based on clinical parameters and immunohistochemical markers: a multi-institutional study

Objective

This study aimed to investigate the prognosis value of the clinical parameters and immunohistochemical markers of patients with early-onset endometrial cancer (EC) and establish a nomogram to accurately predict recurrence-free survival (RFS) of early-onset EC after resection.

Methods

A training dataset containing 458 patients and an independent testing dataset consisting of 170 patients were employed in this retrospective study. The independent risk factors related to RFS were confirmed using Cox regression models. A nomogram model was established to predict RFS at 3 and 5 years post-hysterectomy. The C-index, area under the curve (AUC) of the receiver operating characteristic (ROC) curve, and calibration curve were calculated to assess the predictive accuracy of the nomogram.

Results

In all early-onset EC patients, more than half (368/628, 58.6%) were diagnosed in the age range of 45-49 years. Meanwhile, the recurrence rate of early-onset EC is approximately 10.8%. Multivariate Cox regression analyses showed that histological subtype, FIGO stage, myometrial invasion, lymphovascular space invasion (LVSI), P53 expression, and MMR status were independent prognostic factors related to RFS (all P < 0.05) and established the nomogram predicting 3- and 5-year RFS. The C-index and calibration curves of the nomogram demonstrated a close correlation between predicted and actual RFS. Patients were divided into high- and low-risk groups according to the model of RFS.

Conclusions

Combining clinical parameters and immunohistochemical markers, we developed a robust nomogram to predict RFS after surgery for early-onset EC patients. This nomogram can predict prognosis well and guide treatment decisions.

Abnormal p53 expression is associated with poor outcomes in grade I or II, stage I, endometrioid carcinoma: a retrospective single-institute study

OBJECTIVE

The Cancer Genome Atlas study revealed an association between copy-number high (p53 abnormal) genetic mutation and poor prognosis in endometrial cancer in 2013. This retrospective study investigated outcomes in patients with abnormal p53 expression and stage I, low-grade endometrial endometrioid carcinoma (EEC).

METHODS

We enrolled women with stage I, grade 1 or 2 EEC who received comprehensive staging and adjuvant therapy between January 2019 and December 2022 at MacKay Memorial Hospital, Taipei, Taiwan. Pathologists interpreted immunohistochemistry stains of cancerous tissues to detect p53 mutation. We compared recurrence, survival, progression-free survival, and overall survival between p53 abnormal and p53 normal groups.

RESULTS

Of the 115 patients included, 26 had pathologically confirmed abnormal p53 expression. Of these 26 patients, five (19.2%) experienced recurrence, and two died due to disease progression. By contrast, no patients in the normal p53 group experienced disease recurrence or died due to disease progression. Significant intergroup differences were discovered in recurrent disease status (19.4% vs. 0%, p<0.001), mortality (7.7% vs. 0%, p<0.001), and progression-free survival (p<0.001). The overall survival (p=0.055) also showed powerful worse trend.

CONCLUSION

For patients with stage I, low-grade EEC, abnormal p53 expression may be used as an indicator of poor prognosis. Therefore, we suggest considering aggressive adjuvant therapies for these patients.

Morphomolecular Correlation and Clinicopathologic Analysis in Endometrial Carcinoma

Research groups have identified 4 groups [polymerase epsilon (POLE) mutant, mismatch repair-deficient, p53-abnormal, and no specific molecular profile)] reflecting the Tumor Cancer Genomic Atlas Research Network subgroups in endometrial carcinomas, improving the clinical applicability of molecular classification. We have analyzed the histopathologic and prognostic characteristics of our cases based on the ProMisE classification, supported by growing data on recommended treatment regimens. The study included 118 cases of endometrial carcinoma diagnosed between 2016 and 2020, which underwent mismatch repair and p53 immunohistochemistry. Next-generation sequencing was performed for POLE mutation analysis, dividing the cases into 4 subgroups. The histopathologic and clinical characteristics of these groups were then analyzed statistically. Four cases(3.4%) were classified as POLE mutant, 31 (26.3%) as mismatch repair-deficient, 22 (18.6%) as p53 mutant, and 61 (51.7%) as no specific molecular profile. We categorized 118 patients with endometrial carcinoma into low (n=43), intermediate (n=28), high-intermediate (n=21), high (n=22), and advanced metastatic (n=4) risk groups regardless of the molecular subtypes of their disease. When we reclassified all cases according to the molecular subtypes of endometrial carcinoma only the risk group of 3 (2.5%) cases changed. Using the new algorithm we designed, after narrowing down the number of patients, the microcystic, elongated, and fragmented pattern of invasion was revealed as an independent prognostic factor that reduces overall survival time (hazard ratio: 16.395, 95% CI: 2.140-125.606, P =0.007). In conclusion, using the new algorithm we have designed, and by identifying patients for whom molecular classification could alter risk groups, we observed that molecular tests can be utilized more efficiently in populations with limited economic resources and, in doing so, we discovered a new morphologic marker with prognostic significance.

Unraveling the Heterogeneity of Deficiency of Mismatch Repair Proteins in Endometrial Cancer: Predictive Biomarkers and Assessment Challenges

Endometrial cancer (EC) poses a significant global health challenge, with increasing prevalence in 26 of 43 countries and over 13,000 deaths projected in the United States by 2024. This rise correlates with aging populations, the obesity epidemic, and changing reproductive patterns, including delayed childbearing. Despite the early diagnosis in 67% of cases, approximately 30% of cases present with regional or distant spread, leading to nearly 20% mortality rates. Unlike many cancers, EC mortality rates are escalating, outpacing therapeutic advancements until recently. One of the reasons for this was the lack of effective therapeutic options for advanced disease until recently. The introduction of immunotherapy has marked a turning point in EC treatment, particularly benefiting patients with defects in mismatch repair proteins (dMMRs). However, dMMR status alone does not ensure a favorable response, underscoring the need for precise patient selection. This review explores the pivotal role of mismatch repair proteins in EC, emphasizing their heterogeneity, the challenges in their assessment, and their potential as predictive biomarkers.

Endometrial Cancer Classification and Management in the Molecular Subtyping Era

A 65-year-old woman presented with a 6-month history of postmenopausal vaginal bleeding, and endometrial biopsy showed grade 2 endometrioid adenocarcinoma. What would you do next?

The impact of estrogen receptor and L1 cell adhesion molecule expression on endometrial cancer outcome correlates with clinicopathological risk group and molecular subgroup

OBJECTIVE

To assess the risk stratification of clinicopathologically and molecularly classified endometrial cancer based on estrogen receptor (ER) and L1 cell adhesion molecule (L1CAM) expression.

METHODS

This was a retrospective study of patients who underwent primary treatment at a single tertiary center. Carcinomas were classified into 5 clinicopathological risk groups, as per European guidelines. Immunohistochemistry and polymerase-ϵ sequencing were conducted for molecular classification and determination of ER and L1CAM expression.

RESULTS

Data from 1044 patients were analyzed. The median follow-up was 67.5 months. In univariable analyses, ER expression correlated with improved disease-specific survival (DSS) in the "no specific molecular profile" (NSMP) (P < 0.001) and mismatch repair deficient (MMRd) (P = 0.002) subgroups. Negative L1CAM expression was associated with enhanced DSS in the NSMP subgroup alone (P < 0.001). ER (hazard ratio [HR] 0.18), but not L1CAM, exhibited prognostic significance within NSMP when controlling for parameters available at the time of diagnosis (tumor histotype, grade, age). ER and L1CAM were not independently associated with DSS within NSMP when controlling for parameters available after surgery (clinicopathological risk groups, age, adjuvant therapy). However, in high-risk-advanced-metastatic cases, both ER (HR 0.26) and L1CAM (HR 3.9) independently correlated with DSS. Similarly, within MMRd, ER was associated with improved DSS in high-risk-advanced-metastatic carcinomas (HR 0.42).

CONCLUSION

The prognostic significance of ER and L1CAM varies across clinicopathological risk groups and molecular subgroups of endometrial cancer. Notably, risk assessment for high-risk-advanced-metastatic NSMP and MMRd subtype carcinomas can be refined by ER status.

Advanced endometrial cancer-The next generation of treatment: A society of gynecologic oncology journal club clinical commentary

In February of 2024, the Society of Gynecologic Oncology (SGO) hosted a journal club focused on new treatment options for the management of advanced and metastatic endometrial cancer. This clinical commentary is intended to provide a summary report of that presentation. The session described the importance of molecular characterization shown in the work of The Cancer Genome Atlas (TCGA). The updated 2023 FIGO staging of endometrial cancer was reviewed. The panel then described the role of upfront immunotherapy for the treatment of advanced or recurrent endometrial cancer as demonstrated in four recent trials (RUBY, NRG-GY018, AtTEnd, and DUO-E studies). The DUO-E study uniquely examined the combination immunotherapy with a PARP inhibitor. The trials had unique differences in inclusion criteria, primary outcomes, and length of maintenance therapy, but all boasted similarly promising results particularly in mismatch repair deficient (dMMR) endometrial cancer. This era of rapid innovation in advanced and recurrent endometrial cancer will hopefully enhance individualized treatment approaches and improved outcomes for patients with endometrial cancer.

Comprehensive molecular characterization of early stage grade 3 endometrioid endometrial adenocarcinoma

OBJECTIVE

The treatment for stage IB grade 3 endometrioid endometrial adenocarcinoma is challenging with variable practice. Molecular characterization may help identify adjuvant therapy strategies beyond stage. We aimed to better understand the molecular features of these tumors by characterizing them by ProMisE classification, mutational signature, and commonly mutated genes.

METHODS

Patients with stage IB grade 3 EEC at two institutions were included. Immunohistochemistry and whole exome sequencing were performed on archival FFPE tissue sections to determine ProMisE classification. Personal Cancer Genome Reporter was used for somatic variant annotation, and mutational signatures were generated based on COSMIC single base substitution mutational signatures.

RESULTS

46 patients were included with variable adjuvant treatment. Nine patients recurred (19.6%), most with extra-abdominal disease (n = 5, or 55.6%). 10 had POLE mutations (21.7%), 18 were MMR deficient (39.1%), 6 had abnormal p53 (13.0%), and 12 were p53 wildtype (26.1%). There were no recurrences in the POLE subgroup. A dominant mutational signature was identified in 38 patients: 17 SBS5 signature (44.7%), 10 SBS15 or SBS44 signature (26.3%), 7 SBS10a or SBS10b signature (18.4%), 3 SBS14 signature (7.9%), and 1 SBS40 signature (2.6%). The six patients that recurred had a SBS5 signature. Frequently mutated genes included ARID1A (n = 30, 65%), PTEN (n = 28, 61%), MUC16 (n = 27, 59%), and PIK3CA (n = 25, 54%).

CONCLUSIONS

This comprehensive evaluation found a molecularly diverse cohort of tumors, despite the same histology, stage and grade. Mutational signature SBS5 correlated with a high risk of recurrence. Further refining of endometrial cancer classification may enable more precise patient stratification and personalized treatment approaches.

Endometrioid ovarian carcinoma landscape: pathological and molecular characterization

Endometrioid ovarian cancers (EOvC) are usually managed as serous tumors. In this study, we conducted a comprehensive molecular investigation to uncover the distinct biological characteristics of EOvC. This retrospective multicenter study involved patients from three European centers. We collected clinical data and formalin-fixed paraffin-embedded (FFPE) samples for analysis at the DNA level using panel-based next-generation sequencing and array-comparative genomic hybridization. Additionally, we examined mRNA expression using NanoString nCounter® and protein expression through tissue microarray. We compared EOvC with other ovarian subtypes and uterine endometrioid tumors. Furthermore, we assessed the impact of molecular alterations on patient outcomes, including progression-free survival (PFS) and overall survival (OS). Preliminary analysis of clinical data from 668 patients, including 86 (12.9%) EOvC, revealed more favorable prognosis for EOvC compared with serous ovarian carcinoma (5-year OS of 60% versus 45%; P = 0.001) driven by diagnosis at an earlier stage. Immunohistochemistry and copy number alteration (CNA) profiles of 43 cases with clinical data and FFPE samples available indicated that EOvC protein expression and CNA profiles were more similar to endometrioid endometrial tumors than to serous ovarian carcinomas. EOvC exhibited specific alterations, such as lower rates of PTEN loss, mutations in DNA repair genes, and P53 abnormalities. Survival analysis showed that patients with tumors harboring loss of PTEN expression had worse outcomes (median PFS 19.6 months vs. not reached; P = 0.034). Gene expression profile analysis confirmed that EOvC differed from serous tumors. However, comparison to other rare subtypes of ovarian cancer suggested that the EOvC transcriptomic profile was close to that of ovarian clear cell carcinoma. Downregulation of genes involved in the PI3K pathway and DNA methylation was observed in EOvC. In conclusion, EOvC represents a distinct biological entity and should be regarded as such in the development of specific clinical approaches.

New clinicopathological concept of endometrial carcinoma with integration of histological features and molecular profiles

The dual-stratified pathway of endometrial carcinomas (ECs) has long been dominant. However, in 2013, The Cancer Genome Atlas (TCGA) defined four EC subgroups with distinctive prognoses. Inspired by TCGA, in 2018, the Proactive Molecular Risk Classifier for Endometrial Cancer (ProMisE) provided four pragmatic molecular classifiers to apply surrogate immunohistochemical markers to TCGA subgroup categorization. These trends prompted the revision of 2020 WHO Classification of Female Genital Tumors, 5th edition (2020 WHO classification), in which four molecular subtypes are recognized: POLE-ultramutated; mismatch repair-deficient; p53-mutant; and no specific molecular profile. In the 2020 WHO classification, the diagnostic algorithm is characterized by prioritizing POLEmut over other molecular abnormalities. Following the 2020 WHO classification, Federation of International Gynecology and Obstetrics (FIGO) proposed a new staging system in 2023. The updated system focuses on diagnostic parameters, such as histological type and grade, lymphovascular space invasion, and molecular alterations. These new histomolecular diagnostic concepts of ECs are being accordingly introduced into the routine pathology practice. For the first time, the 2020 WHO classification includes mesonephric-like adenocarcinoma (MLA) as a novel histological entity, mimicking the conventional mesonephric adenocarcinoma, but is considered of Müllerian ductal origin.