Molecular subtype diagnosis of endometrial carcinoma: comparison of the next-generation sequencing panel and Proactive Molecular Risk Classifier for Endometrial Cancer classifier

Genetic predictors of unexpected recurrence in low-risk endometrial cancer: A comprehensive genomic analysis reveals FGFR2 as a risk factor and a rare fatal POLE-mutated recurrence

OBJECTIVE

Endometrial cancer is the most common gynecological malignancy in high-income countries. While early-stage endometrial cancer generally has a favorable prognosis, a small proportion of low-risk patients experience unexpected recurrence. This study aimed to identify molecular factors contributing to recurrence in stage 1 A grade 1-2 low-risk endometrioid endometrial cancer.

METHODS

We performed next-generation sequencing (NGS) on tumor samples from 19 patients who experienced recurrence despite favorable clinicopathological features and compared them with six control patients without recurrence. Results were also compared to a matched cohort of low-risk endometrial cancers from The Cancer Genome Atlas (TCGA) database.

RESULTS

Mutations in PTEN, PIK3CA, ARID1A, and FGFR2 were the most frequent in the recurrence group. FGFR2 mutations were exclusive to the recurrence group (9/19, 47.4 %) and absent in the non-recurrent group (0/6), a difference approaching statistical significance (p = 0.0571). FGFR2 mutations were also significantly more prevalent in the recurrence cohort compared to the TCGA low-risk cohort (p = 0.0039). Prominent FGFR2 missense mutations included S252W, K659E, and N549K, which may drive oncogenesis and tumor progression. Among the recurrence group, a rare POLE-mutated tumor recurred unexpectedly and proved fatal, highlighting the potential for poor outcomes even in typically favorable molecular subtypes.

CONCLUSION

FGFR2 mutations may play a role in tumor recurrence in a subset of low-risk endometrial cancers, underscoring the importance of molecular profiling in identifying patients at risk. FGFR2 represents a potential therapeutic target, warranting further validation in larger cohorts to establish its clinical utility.

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.

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.

Meta-analysis of the ability of mutational profiles on the cancer genome atlas to predict prognosis in endometrial carcinoma

BACKGROUND

In 2013, The Cancer Genome Atlas Research Network suggested that endometrial carcinoma patients may be reclassified into four molecular prognostic groups.

OBJECTIVE

To compare survival of endometrial carcinoma patients with different mutational profiles.

SEARCH STRATEGY

Studies reporting survival of endometrial carcinoma patients were identified through systematic searches of four databases.

SELECTION CRITERIA

We included relevant studies based on the literature type, data integrity and the methodological quality.

DATA COLLECTION AND ANALYSIS

The pooled survival data were compared among patients with different mutational profiles. Heterogeneity in the pooled data was assessed using the I2 statistic.

MAIN RESULTS

Data were meta-analyzed from nine studies involving 4755 patients, who were classified into the following mutational profiles: p53abn, 745 patients (15.6%); MMRd, 1454 patients (30.6%); POLEmut, 351 patients (7.4%); and p53wt, 2205 patients (46.4%). Compared to the p53wt group, the p53abn group showed significantly worse overall survival (OS) (HR 2.31, 95% CI: 1.67-3.19), progression-free survival (PFS) (HR 2.86, 95% CI: 1.45-5.64) and disease-specific survival (HR 2.60, 95% CI: 1.41-4.79); and the MMRd group showed significantly worse OS (HR 1.30, 95% CI: 1.11-1.53) and PFS (HR 1.27, 95% CI: 1.01-1.59). The POLEmut group, in contrast, showed similar survival as the p53wt group.

CONCLUSIONS

The four mutational profiles for patients with endometrial carcinoma in the Cancer Genome Atlas for Endometrial Cancer are associated with worse to better survival in the trend: p53abn < MMRd < POLEmut ≈ p53wt. Mutational profiling may be useful for stratifying endometrial carcinoma patients by survival risk, which in turn may improve their management.

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.

Is HOXA5 a Novel Prognostic Biomarker for Uterine Corpus Endometrioid Adenocarcinoma?

Endometrial cancer (EC) is one of the most pervasive malignancies in females worldwide. HOXA5 is a member of the homeobox (HOX) family and encodes the HOXA5 protein. HOXA5 is associated with various cancers; however, its association with EC remains unclear. This study aimed to determine the association between HOXA5 gene expression and the prognosis of endometrioid adenocarcinoma, a subtype of EC (EAEC). Microarray data of HOXA5 were collected from the Gene Expression Omnibus datasets, consisting of 79 samples from GSE17025 and 20 samples from GSE29981. RNA-sequencing, clinical, and survival data on EC were obtained from The Cancer Genome Atlas cohort. Survival analysis revealed that HOXA5 overexpression was associated with poor overall survival in patients with EAEC (p = 0.044, HR = 1.832, 95% CI = 1.006-3.334). Cox regression analysis revealed that HOXA5 was an independent risk factor for poor prognosis in EAEC. The overexpression of HOXA5 was associated with a higher histological grade of EAEC, and it was also associated with TP53 mutation or the high copy number of EC. Our findings suggest the potential of HOXA5 as a novel biomarker for predicting poor survival outcomes in patients with EAEC.

Harmonized molecular classification; assessment of a single-test ProMisE NGS tool

OBJECTIVES

Despite recommendations for integrating molecular classification of endometrial cancers (EC) into pathology reporting and clinical management, uptake is inconsistent. To assign ProMisE subtype, all molecular components must be available (POLE mutation status, mismatch repair (MMR) and p53 immunohistochemistry (IHC)) and often these are assessed at different stages of care and/or at different centres resulting in delays in treatment. We assessed a single-test DNA-based targeted next generation sequencing (NGS) molecular classifier (ProMisE NGS), comparing concordance and prognostic value to the original ProMisE classifier.

METHODS

DNA was extracted from formalin-fixed paraffin embedded (FFPE) ECs that had previously undergone ProMisE molecular classification (POLE sequencing, IHC for p53 and MMR). DNA was sequenced using the clinically validated Imagia Canexia Health Find It™ amplicon-based NGS gene panel assay to assess for pathogenic POLE mutations (unchanged from original ProMisE), TP53 mutations (in lieu of p53 IHC), and microsatellite instability (MSI) (in lieu of MMR IHC),with the same order of segregation as original ProMisE used for subtype assignment. Molecular subtype assignment of both classifiers was compared by concordance metrics and Kaplan-Meier survival statistics.

RESULTS

The new DNA-based NGS molecular classifier (ProMisE NGS) was used to determine the molecular subtype in 164 ECs previously classified with ProMisE. 159/164 cases were concordant with a kappa statistic of 0.96 and an overall accuracy of 0.97. Prognostic differences in progression-free, disease-specific and overall survival between the four molecular subtypes were observed for the new NGS classifier, recapitulating the survival curves of the original ProMisE classifier. ProMisE NGS was 100% concordant between matched biopsy and hysterectomy samples.

CONCLUSION

ProMisE NGS is feasible on standard FFPE material, demonstrates high concordance with the original ProMisE classifier and maintains prognostic value in EC. This test has the potential to facilitate implementation of molecular classification of EC at the time of first diagnosis.

Determination of the Cancer Genome Atlas (TCGA) Endometrial Cancer Molecular Subtypes Using the Variant Interpretation and Clinical Decision Support Software MH Guide

BACKGROUND

The Cancer Genome Atlas (TCGA) network (United States National Cancer Institute) identified four molecular endometrial cancer (EC) subtypes using an extensive multi-method approach. The aim of this study was to determine the four TCGA EC molecular subtypes using a single-method whole-exome sequencing (WES)-based approach provided by MH Guide (Molecular Health, Heidelberg, Germany).

METHODS

WES and clinical data of n = 232 EC patients were obtained from TCGA. The four TCGA EC molecular subtypes designated as (i) Mutated Polymerase ε (POLE), (ii) Microsatellite Instability (MSI), (iii) Copy Number (CN) low and, (iv) CN-high were determined using the MH Guide software. The prognostic value of the subtypes determined by MH Guide were compared with the TCGA classification.

RESULTS

Analysis of WES data using the MH Guide software led to the precise identification of the four EC molecular subtypes analogous to the TCGA classification. Both approaches displayed high concordance in terms of prognostic significance.

CONCLUSIONS

The multi-method-based TCGA EC molecular subtypes can reliably be reproduced by the single-method-based MH Guide approach. The easy-to-implement single-method MH Guide approach represents a promising diagnostic tool.

Clinical characteristics and prognostic characterization of endometrial carcinoma: a comparative analysis of molecular typing protocols

BACKGROUND

Endometrial carcinoma (EC) is one of the most common gynecological malignancies in China and globally, accounting for the fourth-prevalent cancer in women. Although numerous studies have confirmed prognostic value of The Cancer Genome Atlas (TCGA) molecular subgroups, it is unclear how they are combined with histological features. The main objective of this study was to compare ProMisE and TCGA classification for the rapid and accurate prediction of prognosis within EC patients, together with the provision of a revised strategy for individualized diagnosis and treatment of patients.

METHODS

Within this study, 70 patients with EC from Beijing Tsinghua Changgeng Hospital (affiliated to Tsinghua University) were retrospectively examined between July 2015 and December 2021. Samples were processed for determination of clinical markers, together with ProMisE and TCGA classification.

RESULTS

Comparative analysis across four TCGA types (POLE, Low-CN, High-CN, and MSI-H) and age, was statistically significant (χ²= 7.000, p = 0.029). There was no significant difference observed among the four TCGA types and FIGO stage, vascular invasion and depth of invasion, or lymph node metastasis and tumor area. There was no significant association between the expression of Vimentin, Ki-67, PTEN, MSH2, PAX-8, β-catenin, CD10, ER, PR, P16, MLH1, and PMS2 with the four TCGA types. In addition, p63 expression (χ²= 11.09, p = 0.029) and p53 expression (χ²= 11.585, p = 0.005) were statistically significant. Numerous models demonstrated that patients with POLE mutations and low-CN had higher progression free survival (PFS) and overall survival (OS), whereas those with high-CN had lowest values. The log-rank test revealed that the survival rate of PR-positive and ER-positive patients was significantly higher (p < 0.001).

CONCLUSION

Overall, these results can be of additional benefit for clinical applications, in comparison to the ProMisE classification method. In addition, PR, ER, vascular infiltration, hyperlipidemia and atherosclerosis were found to be the key factors affecting EC prognosis.

Application of NGS molecular classification in the diagnosis of endometrial carcinoma: A supplement to traditional pathological diagnosis

OBJECTIVE

This study aims to demonstrate the advantages of NGS molecular classification in EC diagnosis and to assess whether molecular classification could be performed on curettage specimens and its concordance with subsequent hysterectomy specimens.

METHODS

80 patients with hysterectomy specimens and 35/80 patients with paired curettage specimens were stratified as POLE mut, MSI-H, TP53 wt, or TP53 abn group by NGS panel. Histotype, tumor grade, IHC results, and other pathological details were taken from original pathological reports.

RESULTS

The correlation analysis of 80 patients with hysterectomy specimens between NGS molecular classification and clinicopathological characters displayed that the POLE mut group was associated with EEC (87.5%) and TP53 abn subtype was correlated to a later stage (Stage II-IV, 47.6%), G3 (76.2%), serous histology (61.9%) and myometrial invasion ≥50% (47.6%). A favorable concordance (31/32, 96.9%) was shown in MSI analysis and MMR IHC results, and the agreement rate of p53 IHC and TP53 mutation was 81.5% (53/65). Compared with the p53 IHC abnormal group, the TP53 mutation group had a higher correlation with high-risk factors. A high level of concordance (31/35, 88.0%) of NGS molecular classification was achieved between curettage specimens and hysterectomy specimens while grade and histotype (including unclassified group) from curettage specimens and hysterectomy specimens showed only moderate levels of agreement, 54.3% (19/35) and 68.6% (24/35), respectively.

CONCLUSION

NGS molecular classification achieved on curettage samples showed high concordance with the final hysterectomy specimens, demonstrating superior to the conventional pathological assessment of grade and histotype and potential utilization in clinical practice.

Fertility Preservation in Endometrial Cancer-Treatment and Molecular Aspects

Endometrial cancer is one of the most common gynecological malignancies worldwide; incidences are rising, with 417,367 new cases registered in 2020. Of these, the proportion of women that are of reproductive age is around 4-14% and the number is increasing. Thus, in addition to oncological therapy and safety, the preservation of fertility plays a central role in therapeutic strategies. Molecular genetic patient data provide a robust supplementary benefit that improves primary risk assessment and can help design personalized treatment options to curtail over- and undertreatment and contribute to fertility preserving strategies. The aim of our review is to provide an overview of the latest significant recommendations in the diagnosis and therapy of endometrial cancer during reproductive age. In this paper the most recent groundbreaking molecular discoveries in endometrial cancer are highlighted and discussed as an opportunity to enhance the prognostic and therapy options in this special patient collective.

Histopathological and molecular findings in 98 cases of endometrial carcinoma: MMR, p53 and next generation sequencing

Gynecological malignancies arise from hereditary and somatic mutations, transcriptional aberrations, and genomic alterations influenced by epigenetic factors. This study aims to identify the mutations and their frequency in endometrial carcinomas (EC), and furthermore, to determine the relationship of these mutations with histopathological and immunohistochemical (IHC) parameters. The study was carried out in a retrospective cohort of 98 patients who received treatment upon being diagnosed with EC at a tertiary university hospital in Turkey between 2016 and 2021. The NGS-DNA tumor panel containing 29 genes was used in the study. NGS data of the cases were obtained from state of the evidence Tier 1 and 2 mutations. The relationship of patients' next generation sequencing (NGS) DNA panel results with histopathological parameters and IHC results (MLH1, MSH2, PMS2, MSH6 and p53) were evaluated. In 59 of the 98 cases, mutations were detected in at least one gene investigated with the NGS DNA panel. The most common somatic mutations in endometrial carcinoma were PIK3CA (33.6%), CTNNB1 (16.3%), KRAS (12.2%) and FGFR2 (11.2%) in this cohort. Abnormal p53 was detected by IHC in 15 out of 75 (20%) cases. Loss of expression was observed in at least one mismatch repair (MMR) protein by means of IHC in 39 out of 72 (39.8%) cases. Metastasis was found in 14 out of 82 (14.3%) patients who underwent lymph node dissection. FGFR2 mutation was more common in the group with lymph node metastasis compared to those without metastasis (p = 0.02). We report the mutational landscape of EC in a tertiary referral hospital in northwestern Turkey. Although our data are very limited, we think that the FGFR2 mutation may be associated with lymph node metastasis, but studies with larger patient numbers and longer follow-up periods are needed.

Molecular classification grade 3 endometrial endometrioid carcinoma using a next-generation sequencing–based gene panel

Over the past two decades, the incidence of endometrial cancer (EC) is increasing, and there is a need for molecular biomarkers to predict prognosis and guide treatment. A recent study from The Cancer Genome Atlas suggested to implement the EC analysis by molecular profile for improving diagnosis, prognosis, and therapeutic treatment. In this study, next-generation sequencing was performed on 70 cases of G3 endometrioid ECs (EECs) using an 11-gene panel (TP53, MLH1, MSH2, MSH6, PMS2, EPCAM, PIK3CA, CTNNB1, KRAS, PTEN, and POL) for molecular classification. The molecular classification based on the 11-gene NGS panel identified four molecular subgroups: POLE-ultramutated (n = 20, 28.6%), MSI-H (n = 27, 38.6%), NSMP (n = 13, 18.6%) and TP53mut (n = 10, 14.3%). The NGS method showed 98.6% (69 of 70 cases, kappa value 98%) in concordance with the cases assessed by immunohistochemistry (IHC). Among the seven dead cases, four were MSI-H tumors, two were TP53mut/p53abn tumors, and one was NSMP tumors with an average overall survival (OS) of 14.7 months. TP53mut subgroup showed that poor OS rates and POLE group have favorable prognosis. Our work suggested that the 11-gene panel is suitable for molecular classification in G3 EECs and for guiding prognosis and treatment decisions.

Further refining 2020 ESGO/ESTRO/ESP molecular risk classes in patients with early-stage endometrial cancer: A propensity score-matched analysis

Background

The integration of molecular features with clinicopathological findings in endometrial cancer classification seems to be able to significantly refine risk assessment. Nevertheless, clinical management remains challenging, and different therapeutic options are available for each class. Further prognostic characterization of the subgroups within each risk class could be helpful in the decision‐making process.

Methods

This study evaluated the role of the 2020 European Society of Gynaecological Oncology (ESGO)/European Society for Radiotherapy and Oncology (ESTRO)/European Society of Pathology (ESP) risk assessment system and the three prognostic profiles adopted in the PORTEC‐4a trial in predicting disease‐free and overall survival in a retrospective study cohort of patients with early‐stage endometrial cancer. Patients were selected according to a 1:2 propensity score matching analysis. Moreover, the sequencing of 29 genes was undertaken for tumor samples.

Results

The study included 137 patients. No differences in disease‐free or overall survival at 5 years were observed among the 2020 ESGO/ESTRO/ESP risk classes without molecular features (p = .766 and p = .176, respectively). Once molecular features were integrated, the probability of overall survival was significantly different (p = .011). When the three prognostic profiles were applied, the probability of recurrence had a p value of .097, and significant differences were observed in overall survival (p = .004). Among patients experiencing recurrence, 17.6% showed mutations in BRCA1/2, RAD50, BRIP1, and XRCC2, whereas 22.5% had PD‐L1–positive expression and an MUTYH mutation.

Conclusions

Further stratification within each risk class according to the most relevant prognostic features could better define the prognosis of patients with early‐stage endometrial cancer. Nearly half of the patients who experienced recurrence showed a targetable molecular alteration for which dedicated trials should be encouraged.

The 2020 molecular integrated risk assessment is of crucial importance for better defining the prognosis of patients with early‐stage endometrial cancer. Nevertheless, further stratification within each risk class according to the most relevant prognostic features could better define the biological behavior of the disease and thus allow better tailoring of adjuvant treatment.

EZH2 and Endometrial Cancer Development: Insights from a Mouse Model

Enhancer of zeste homolog 2 (EZH2), a core component of polycomb repressive complex 2, plays an important role in cancer development. As both oncogenic and tumor suppressive functions of EZH2 have been documented in the literature, the objective of this study is to determine the impact of Ezh2 deletion on the development and progression of endometrial cancer induced by inactivation of phosphatase and tensin homolog (PTEN), a tumor suppressor gene frequently dysregulated in endometrial cancer patients. To this end, we created mice harboring uterine deletion of both Ezh2 and Pten using Cre recombinase driven by the progesterone receptor (Pgr) promoter. Our results showed reduced tumor burden in Pten^d/d; Ezh2^d/d mice compared with that of Pten^d/d mice during early carcinogenesis. The decreased Ki67 index in EZH2 and PTEN-depleted uteri versus that in PTEN-depleted uteri indicated an oncogenic role of EZH2 during early tumor development. However, mice harboring uterine deletion of both Ezh2 and Pten developed unfavorable disease outcome, accompanied by exacerbated epithelial stratification and heightened inflammatory response. The observed effect was non-cell autonomous and mediated by altered immune response evidenced by massive accumulation of intraluminal neutrophils, a hallmark of endometrial carcinoma in Pten^d/d; Ezh2^d/d mice during disease progression. Hence, these results reveal dual roles of EZH2 in endometrial cancer development.

Prognosis Stratification Tools in Early-Stage Endometrial Cancer: Could We Improve Their Accuracy?

There are three prognostic stratification tools used for endometrial cancer: ESMO-ESGO-ESTRO 2016, ProMisE, and ESGO-ESTRO-ESP 2020. However, these methods are not sufficiently accurate to address prognosis. The aim of this study was to investigate whether the integration of molecular classification and other biomarkers could be used to improve the prognosis stratification in early-stage endometrial cancer. Relapse-free and overall survival of each classifier were analyzed, and the c-index was employed to assess accuracy. Other biomarkers were explored to improve the precision of risk classifiers. We analyzed 293 patients. A comparison between the three classifiers showed an improved accuracy in ESGO-ESTRO-ESP 2020 when RFS was evaluated (c-index = 0.78), although we did not find broad differences between intermediate prognostic groups. Prognosis of these patients was better stratified with the incorporation of CTNNB1 status to the 2020 classifier (c-index 0.81), with statistically significant and clinically relevant differences in 5-year RFS: 93.9% for low risk, 79.1% for intermediate merged group/CTNNB1 wild type, and 42.7% for high risk (including patients with CTNNB1 mutation). The incorporation of molecular classification in risk stratification resulted in better discriminatory capability, which could be improved even further with the addition of CTNNB1 mutational evaluation.

Investigation of discrepant mismatch repair immunohistochemistry and microsatellite instability polymerase chain reaction test results for gynecologic cancers using next-generation sequencing

Gynecologic cancers are routinely screened for DNA mismatch repair (MMR) gene mutations using immunohistochemistry (IHC) and/or polymerase chain reaction (PCR) for microsatellite instability (MSI) to enable selection of immune checkpoint inhibitor therapy and screen for Lynch syndrome. The limited data that compare IHC and MSI in endometrial tumors have shown discordance rates of 5-10%. We reviewed MMR/MSI results in gynecologic cancers and used next-generation sequencing (NGS) to interrogate discrepancies. Of the 328 cases with both IHC and MSI results, 256 (78.0%) were microsatellite stable (MSS) with preserved MMR (pMMR), 64 (19.5%) cases were MSI-High (MSI-H) with MMR deficient (dMMR), 2 cases showed subclonal loss of MLH1 and PMS2 with MSI-H, and 6 cases were discordant. Overall, there was a 98.2% (322/328) IHC/MSI concordance. Discordant cases were retested and/or subject to NGS. Of the six discrepant cases, five showed dMMR with MSS and one showed pMMR with MSI-H. One dMMR/MSI-L case showed loss of PMS2 with a germline pathogenic mutation. The pMMR/MSI-H case was found to harbor pathogenic variants in MLH1 and MSH6. One of the two cases with subclonal populations demonstrated MSI-H in the dMMR area and MSS in the pMMR area. These results emphasize the importance of selecting the appropriate tumor tissue for both IHC and molecular testing and demonstrate that NGS can help resolve discrepant MMR and MSI results.