Genomic landscape of endometrial carcinomas of no specific molecular profile

Copy number variations in endometrial cancer: from biological significance to clinical utility

The molecular basis of endometrial cancer, which is the most common malignancy of the female reproductive organs, relies not only on onset of mutations but also on copy number variations, the latter consisting of gene gains or losses. In this review, we introduce copy number variations and discuss their involvement in endometrial cancer to determine the perspectives of clinical applicability. We performed a literature analysis on PubMed of publications over the past 30 years and annotated clinical information, including histological and molecular subtypes, adopted molecular techniques for identification of copy number variations, their locations, and the genes involved. We highlight correlations between the presence of some specific copy number variations and myometrial invasion, lymph node metastasis, advanced International Federation of Gynecology and Obstetrics (FIGO) stage, high grade, drug response, and cancer progression. In particular, type I endometrial cancer cells have few copy number variations and are mainly located in 8q and 1q, while type II, high grade, and advanced FIGO stage endometrial cancer cells are aneuploid and have a greater number of copy number variations. As expected, the higher the number of copy number variations the worse the prognosis, especially if they amplify CCNE1, ERBB2, KRAS, MYC, and PIK3CA oncogenes. Great variability in copy number and location among patients with the same endometrial cancer histological or molecular subtype emerged, making them interesting candidates to be explored for the improvement of patient stratification. Copy number variations have a role in endometrial cancer progression, and therefore their detection may be useful for more accurate prediction of prognosis. Unfortunately, only a few studies have been carried out on the role of copy number variations according to the molecular classification of endometrial cancer, and even fewer have explored the correlation with drugs. For these reasons, further studies, also using single cell RNA sequencing, are needed before reaching a clinical application.

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.

Molecular Classification of Endometrial Cancer and Its Impact on Therapy Selection

Endometrial cancer (EC) accounts for 90% of uterine cancer cases. It is considered not only one of the most common gynecological malignancies but also one of the most frequent cancers among women overall. Nowadays, the differentiation of EC subtypes is based on immunohistochemistry and molecular techniques. It is considered that patients' prognosis and the implementation of the appropriate treatment depend on the cancer subtype. Patients with pathogenic variants in POLE have the most favorable outcome, while those with abnormal p53 protein have the poorest. Therefore, in patients with POLE mutation, the de-escalation of postoperative treatment may be considered, and patients with abnormal p53 protein should be subjected to intensive adjuvant therapy. Patients with a DNA mismatch repair (dMMR) deficiency are classified in the intermediate prognosis group as EC patients without a specific molecular profile. Immunotherapy has been recognized as an effective treatment method in patients with advanced or recurrent EC with a mismatch deficiency. Thus, different adjuvant therapy approaches, including targeted therapy and immunotherapy, are being proposed depending on the EC subtype, and international guidelines, such as those published by ESMO and ESGO/ESTRO/ESP, include recommendations for performing the molecular classification of all EC cases. The decision about adjuvant therapy selection has to be based not only on clinical data and histological type and stage of cancer, but, following international recommendations, has to include EC molecular subtyping. This review describes how molecular classification could support more optimal therapeutic management in endometrial cancer patients.

Molecular and pathologic data to guide selection of patients with endometrioid endometrial cancer for ovarian preservation

OBJECTIVES

To investigate the association of molecular and pathologic factors with concurrent or recurrent ovarian disease to guide ovarian preservation in endometrioid endometrial cancer.

METHODS

Patients with endometrial cancer ≤50 years of age at diagnosis were grouped by elective oophorectomy versus ovarian preservation at staging (January 2010 to June 2021). Tumors were stratified by molecular sub-type and CTNNB1 mutational status with next generation sequencing and immunohistochemistry. Germline data identified patients with Lynch syndrome. Associations between molecular/pathologic features and concurrent ovarian disease in patients electing oophorectomy were compared with the Wilcoxon rank-sum and Fisher's exact tests. Associations with isolated ovarian recurrences in patients who chose ovarian preservation were examined using survival analyses.

RESULTS

Among 317 patients with endometrial cancer who underwent bilateral oophorectomy, 27 (9%) had malignant ovarian tumors, of whom 11 (41%) had no gross ovarian involvement on intra-operative survey. For patients with sequencing, concurrent malignant ovarian tumors were diagnosed in 0/14 (0%) POLE, 2/48 (4%) copy number-low/no specific molecular profile, 10/22 (45%) microsatellite instability-high, and 3/6 (50%) copy number-high/TP53abnormal patients (p<0.001). Concurrent malignant ovarian tumors were present in 1/30 (3%) hotspot CTNNB1-mutated versus 10/60 (17%) wildtype/CTNNB1 non-hotspot mutated endometrial cancer patients (p=0.11) and 7/28 (25%) Lynch versus 7/74 (9%) non-Lynch syndrome patients (p=0.06). Concurrent malignant ovarian tumors were present in patients with higher grade endometrial cancer (5% grade 1 vs 20% grade 2 and 24% grade 3; p<0.001), present versus absent lymphovascular space invasion (20% vs 6%; p=0.004), positive versus negative pelvic washings (28% vs 7%; p=0.016), and ≥50% versus <50% myoinvasion (24% vs 7%; p=0.004). Of 103 patients who chose ovarian preservation, four had isolated ovarian recurrences (two had high-risk pathologic features and two had high-risk molecular features).

CONCLUSIONS

The integration of molecular and pathologic data may improve risk stratification of pre-menopausal patients with endometrial cancer and enhance candidate selection for ovarian preservation.

Molecular characterization as new driver in prognostic signatures and therapeutic strategies for endometrial cancer

Endometrial cancer (EC) incidence and mortality rates have been increasing, particularly among young females. Although more than 90% of ECs are sporadic, 5-10% are hereditary, a majority of which occurs within Hereditary Non-Polyposis Colorectal Cancer syndrome (HNPCC) or Lynch syndrome. The traditional histopathological classification differentiates EC between two main groups: type I (or endometrioid) and type II (including all other histopathological subtypes). However, this classification lacks reproducibility and does not account for the emerging molecular heterogeneity. In 2013, The Cancer Genome Atlas (TCGA) project proposed EC molecular classification defining four groups with different prognostic and predictive values and the current international guidelines are progressively establishing EC risk stratification and treatment based on both histopathological and molecular criteria. Our manuscript aims to summarize the current state of EC molecular characterizations, including germline alterations at the basis of hereditary EC predisposition, to discuss their clinical utility as prognostic and predictive markers.

Detection of driver mutations and genomic signatures in endometrial cancers using artificial intelligence algorithms

Analyzed endometrial cancer (EC) genomes have allowed for the identification of molecular signatures, which enable the classification, and sometimes prognostication, of these cancers. Artificial intelligence algorithms have facilitated the partitioning of mutations into driver and passenger based on a variety of parameters, including gene function and frequency of mutation. Here, we undertook an evaluation of EC cancer genomes deposited on the Catalogue of Somatic Mutations in Cancers (COSMIC), with the goal to classify all mutations as either driver or passenger. Our analysis showed that approximately 2.5% of all mutations are driver and cause cellular transformation and immortalization. We also characterized nucleotide level mutation signatures, gross chromosomal re-arrangements, and gene expression profiles. We observed that endometrial cancers show distinct nucleotide substitution and chromosomal re-arrangement signatures compared to other cancers. We also identified high expression levels of the CLDN18 claudin gene, which is involved in growth, survival, metastasis and proliferation. We then used in silico protein structure analysis to examine the effect of certain previously uncharacterized driver mutations on protein structure. We found that certain mutations in CTNNB1 and TP53 increase protein stability, which may contribute to cellular transformation. While our analysis retrieved previously classified mutations and genomic alterations, which is to be expected, this study also identified new signatures. Additionally, we show that artificial intelligence algorithms can be effectively leveraged to accurately predict key drivers of cancer. This analysis will expand our understanding of ECs and improve the molecular toolbox for classification, diagnosis, or potential treatment of these cancers.

Molecular features for timely cancer diagnosis and treatment - tumors of the ovary, fallopian tube and endometrium

Gynecologic pathology has moved, within only a few years, from being a diagnostic area devoid of molecular testing into a diagnostic discipline in which such analyses are becoming routine. The direct relevance of molecular characterization to the choice of treatment of patients with carcinomas originating in both the uterus and adnexae makes it likely that such testing will only expand along with our understanding of the molecular make-up of these tumors. As a consequence, gynecologic pathologists have become an integral part of patient management, rather than lab personnel providing external services.In parallel, molecular testing is expanding as a tool for diagnosing rare tumors affecting these organs, including soft tissue tumors, sex cord-stromal tumors and germ cell tumors, as well as other rare entities. Increased knowledge in this area bears directly on the ability to diagnose these tumors in a reproducible manner, as well as recognize and consult on genetic diseases. Hopefully, despite the inherent difficulty in studying rare cancers, it will also translate into new therapeutic options for the malignant ones among these rare cancers.

Moving into the modern era of molecular classification for endometrial cancer

The molecular subtypes of endometrial carcinoma (EC) were first described by The Cancer Genome Atlas (TCGA) a decade ago. Using surrogate approaches, the molecular classification has been demonstrated to be prognostic across EC patients and to have predictive implications. Starting in 2020, the molecular classification has been incorporated into multiple guidelines as part of the risk assessment and most recently into the International Federation of Gynecology and Obstetrics (FIGO) staging. This review article discusses the implementation of the EC molecular classification into clinical practice, the therapeutic implications, and the molecular and clinical heterogeneity of the EC molecular subtypes.

Mesonephric-like adenocarcinoma of the ovary with squamoid morular metaplasia, aberrant β-catenin expression, and concurrent FGFR2 and CTNNB1 mutations: a case report

In general, endometrioid-defining features such as squamoid morular metaplasia are not thought to be associated with mesonephric adenocarcinoma (MA) and mesonephric-like adenocarcinoma (MLA). Here, we report a case of FGFR2-mutated ovarian MLA with squamoid morular metaplasia accompanied by aberrant nuclear and cytoplasmic β-catenin expression and CTNNB1 mutation. Histologically, the tumor showed classical MLA histology, including well-formed glands with intraluminal eosinophilic secretions and cells with papillary thyroid carcinoma-like nuclei. Squamoid morular metaplasia was intimately associated with the tumor. Glandular epithelial elements, including those immediately associated with the squamoid morules, were negative for ER, but positive for both GATA3 and PAX8; aberrant β-catenin expression was limited to the squamoid morules. This case illustrates the ability of mesonephric neoplasia to exhibit histological features previously thought to be restricted to an endometrioid phenotype.

Mesonephric-like adenocarcinoma harbours characteristic copy number variations and a distinct DNA methylation signature closely related to mesonephric adenocarcinoma of the cervix

Mesonephric-like adenocarcinoma (MLA) of the female genital tract is an uncommon histotype that can arise in both the endometrium and the ovary. The exact cell of origin and histogenesis currently remain unknown. Here, we investigated whole genome DNA methylation patterns and copy number variations (CNVs) in a series of MLAs in the context of a large cohort of various gynaecological carcinoma types. CNV analysis of 19 MLAs uncovered gains of chromosomes 1q (18/19, 95%), 10 (15/19, 79%), 12 (14/19, 74%), and 2 (10/19, 53%), as well as loss of chromosome 1p (7/19, 37%). Gains of chromosomes 1q, 10, and 12 were also identified in the majority of mesonephric adenocarcinomas of the uterine cervix (MAs) as well as subsets of endometrioid carcinomas (ECs) and low-grade serous carcinomas of the ovary (LGSCs) but only in a minority of serous carcinomas of the uterine corpus (USCs), clear cell carcinomas (CCCs), and tubo-ovarian high-grade serous carcinomas (HGSCs). While losses of chromosome 1p together with gains of chromosome 1q were also identified in both MA and LGSC, gains of chromosome 2 were almost exclusively identified in MLA and MA. Unsupervised hierarchical clustering and t-SNE analysis of DNA methylation data (Illumina EPIC array) identified a co-clustering for MLAs and MAs, which was distinct from clusters of ECs, USCs, CCCs, LGSCs, and HGSCs. Group-wise comparisons confirmed a close epigenetic relationship between MLA and MA. These findings, in conjunction with the established histological and immunophenotypical overlap, suggest bona fide mesonephric differentiation, and support a more precise terminology of mesonephric-type adenocarcinoma instead of MLA in these tumours. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

New therapeutic targets for endometrial cancer: a glimpse into the preclinical sphere

INTRODUCTION

Endometrial cancer (EC) is the only gynecologic malignancy showing increasing trends in incidence and mortality. While standard treatment has been effective primarily for early-stage EC, precision medicine with tailored therapy has revolutionized the management of this disease. Genome sequencing analyses have identified four sub-types of EC. Treatments for primary and metastatic disease can now be tailored more accurately to achieve better oncologic results.

AREAS COVERED

This review provides an overview of the most relevant and updated evidence in the literature regarding EC molecular analysis and its role in risk classification, prognostication, and guidance for tailored and target therapies in early and advanced/metastatic stages. In addition, it provides updated information on optimal surgical management based on molecular classification and highlights key advances and future strategies.

EXPERT OPINION

EC molecular analysis yields the potential of tailoring adjuvant treatment by escalating or deescalating therapy, as shown for POLE-mutated and p53-mutated tumors. Moreover, the expression of specific molecular signatures offers the possibility to employ novel target therapies, such as immune-checkpoint inhibitors that have demonstrated a significant benefit on prognosis. New treatment guidelines are still being established, and ongoing studies are exploring the potential prognostic role of further sub-stratifications of the four molecular classes and treatment options.

TERT promoter mutations and gene amplification in endometrial cancer

OBJECTIVE

To assess the clinicopathologic, molecular profiles, and survival outcomes of patients with endometrial carcinomas (ECs) harboring telomerase reverse transcriptase (TERT) hotspot mutations or gene amplification.

METHODS

ECs harboring somatic TERT promoter hotspot mutations or gene amplification (TERT-altered) were identified from 1944 ECs that underwent clinical tumor-normal sequencing from 08/2016-12/2021. Clinicopathologic variables, somatic mutation profiles, and survival outcomes of TERT-alt and TERT-wild-type EC were assessed.

RESULTS

We identified 66 TERT-altered ECs (43 TERT-mutated and 23 TERT-amplified), representing 3% of the unselected ECs across histologic subtypes. Most TERT-altered ECs were of copy number (CN)-high/TP53abn molecular subtype (n = 40, 60%), followed by microsatellite-unstable (MSI-H) or CN-low/no specific molecular profile (NSMP)(n = 13, 20% each). TERT-amplified and TERT-mutated ECs were molecularly distinct, with TERT-amplified ECs being more genomically instable and more frequently harboring TP53 and PPP2R1A alterations (q < 0.1). Compared to TERT-wild-type ECs, TERT-altered ECs were more commonly of CN-H/TP53abn molecular subtype (31% vs 57%, p = 0.001), serous histology (10% vs 26%, p = 0.004), and were significantly enriched for TP53, CDKN2A/B, and DROSHA somatic genetic alterations (q < 0.1). Median progression-free survival was 18.7 months (95% CI 11.8-not estimable [NE]) for patients with TERT-altered EC and 80.9 months (65.8-NE) for patients with TERT-wild-type EC (HR 0.33, 95% CI 0.21-0.51, p < 0.001). Similarly, median overall survival was 46.7 months (95% CI 30-NE) for TERT-altered EC patients and not reached for TERT-wild-type EC patients (HR 0.24, 95% CI 0.13-0.44, p < 0.001).

CONCLUSION

TERT-altered ECs, although rare, are enriched for CN-high/TP53abn tumors, TP53, CDKN2A/B and DROSHA somatic mutations, and independently predict worse survival outcomes.

Molecular subtyping in endometrial cancer: A promising strategy to guide fertility preservation

OBJECTIVES

To investigate the association of molecular subtype with progesterone response in patients with endometrial cancer (EC) or atypical endometrial hyperplasia (AEH).

METHODS

Premenopausal patients aged ≤48 years with tumor-normal sequencing data who received progesterone for EC/AEH from 1/1/2010-6/30/2021 were identified. Tumors were classified as POLE-ultramutated, microsatellite instability-high (MSI-H), copy number-high (CN-H), or copy number-low (CN-L) molecular subtype. Best response to progesterone was compared by subtype. Appropriate statistical tests were performed.

RESULTS

Of 20 patients, 7 (35%) had AEH and 13 (65%) had EC. Sixteen tumors (80%) were CN-L, 3 (15%) were MSI-H, and 1 (5%) was POLE-ultramutated. Median time on progesterone was 22 months (range, 3-115). Ten patients (50%) had complete response (CR); median time to CR was 9 months (range, 3-32). Four patients (20%) had stable disease (SD) and 6 (30%) had progressive disease (PD). For CN-L tumors, 10 patients (62%) had CR, 3 (19%) had SD, and 3 (19%) had PD. For MSI-H tumors, 1 patient (33%) had SD and 2 (66%) had PD. For POLE-ultramutated tumors, 1 patient had PD. Median follow-up was 48 months (range, 12-123). Four of 10 patients (40%) with CR recurred; median time from CR to recurrence was 16 months (range, 5-102).

CONCLUSION

Molecular subtype may be associated with progesterone response in patients with EC/AEH. CN-L tumors had the best response, and MSI-H tumors had the poorest. Recurrence after CR is common, and close surveillance is warranted. Larger studies investigating the role of molecular classification in medical management of EC/AEH are needed.

Immune signatures of the POLE mutation in endometrial carcinomas: a systematic study based on TCGA data and clinical cohort validation

Background

POLE is a critical biomarker for endometrial cancer (ECs) prognosis and therapeutic decision. However, the immune infiltration and immunotherapy-related gene expression in the tumor microenvironment (TME) of POLE-mutated ECs remain unresolved.

Methods

The TCGA database was used to characterize the TME of POLE mutants, which primarily included immune cells and co-expression genes. We used immunohistochemistry (IHC) to determine immune cell abundance and PD-L1 expression in 104 EC tissues, including 11 POLE mutants and 93 wild-type.

Results

The bioinformatic study found significant differences in gene expression of the chemokine family, immune-cell markers, and lysozyme in POLE mutants, along with immune response activation. In POLE-mutated ECs, the abundance of CD4+T, CD8+T, M1 macrophages, and dendritic cells increased considerably. Furthermore, POLE mutations may enhance immune cell recruitment or activation and lymphocyte homing in ECs. POLE mutants also had increased expression of immune-checkpoint suppressor genes such as PD-L1, CTLA-4, TIM-3, and others. The tumor mutation burden (TMB) was higher in ECs with POLE mutation. In the validation cohort, we discovered that POLE mutations were related to the immune infiltration abundance of CD8+, CD4+, and Foxp3+ cells and PD-L1 expression by IHC. The prognosis of TCGA-ECs showed that the survival time of the CD8, CD4, PD-L1, or Foxp3 over-expression subgroup of the POLE mutants was significantly prolonged compared to the down-regulation subgroup or the POLE wild-type.

Conclusion

The infiltration abundance of CD8+ T, CD4+ T, Foxp3+ T cells, and the expression of PD-L1 harbor crucial value for the prognosis or individualized therapy of POLE-mutated ECs.

[Molecular classification of endometrial carcinoma-a short summary for clinical use]

BACKGROUND

Histopathological examination is still the backbone for the diagnosis and treatment decision making in endometrial carcinoma (EC). The binary classification of EC into type 1 (mostly endometrioid) and type 2 (mostly serous), although still helpful, showed overlapping clinical, morphological and molecular features and was not very prognostic discriminatory for all subtypes of EC.

METHODS

Analysing the most recent studies dealing with the molecular classification of EC and the recommendations of the German S3-guidelines for EC.

RESULTS AND CONCLUSION

Based on the comprehensive molecular study of The Cancer Genome Atlas Project (TCGA) four distinct molecular subtypes have been identified: EC with POLE mutation (POLEmut), with loss of mismatch repair proteins (MMR deficiency; dMMR), or with TP53 mutation (p53mut) and without any of these alterations, termed NSMP (no specific molecular profile). The molecular classification of EC presents a morphomolecular approach, based on histopathological evaluation (tumor diagnosis, subtyping, grading), immunohistochemistry (MMR, p53) and molecular analyses for POLE. The incorporation of this molecular classification is recommended for clinical use by the World Health Organisation (WHO) as well as many national guidelines and international societies. Due to the heterogeneity of NSMP-EC, which is the largest molecular group, additional research is indicated to further characterise these tumors.

Expression of PD-1 and PD-L1 in Endometrial Cancer: Molecular and Clinical Significance

The landscape of diagnosing and treating endometrial cancer is undergoing a profound transformation due to the integration of molecular analysis and innovative therapeutic approaches. For several decades, the cornerstone treatments for endometrial cancer have included surgical resection, cytotoxic chemotherapy, hormonal therapy, and radiation therapy. However, in recent years, the concept of personalised medicine has gained momentum, reshaping the way clinicians approach cancer treatment. Tailoring treatments based on specific biomarkers has evolved into a standard practice in both initial and recurrent therapy protocols. This review aims to provide an in-depth exploration of the current state of molecular analysis and treatment strategies in the context of endometrial cancer, focusing on the immunological aspect of the PD-1/PD-L1 axis. Furthermore, it seeks to shed light on emerging and innovative approaches that hold promise for the future modulation of endometrial cancer treatments. In essence, as researchers delve into the complex molecular landscape of endometrial cancer and harness the understanding of the PD-1/PD-L1 axis, we are paving the way for more targeted, effective, and personalised therapies that have the potential to significantly improve the outcomes and quality of life for patients with this challenging disease.

The Significance of International Federation of Gynecology and Obstetrics Grading in Microsatellite Instability-High and POLE-Mutant Endometrioid Endometrial Carcinoma

With the advancement of diagnostic molecular technology and the molecular classification of endometrial endometrioid carcinoma (EEC), it remains to be seen whether conventional International Federation of Gynecology and Obstetrics (FIGO) grading retains clinical significance in certain molecular subtypes of EECs. In this study, we explored the clinical significance of FIGO grading in microsatellite instability-high (MSI-H) and POLE-mutant EECs. A total of 162 cases of MSI-H EECs and 50 cases of POLE-mutant EECs were included in the analysis. Significant differences in tumor mutation burden (TMB), progression-free survival, and disease-specific survival were seen between the MSI-H and POLE-mutant cohorts. Within the MSI-H cohort, there were statistically significant differences in TMB and stage at presentation across FIGO grades, but not survival. Within the POLE-mutant cohort, there was significantly greater TMB with increasing FIGO grade, but there were no significant differences in stage or survival. In both the MSI-H and POLE-mutant cohorts, log-rank survival analysis showed no statistically significant difference in progression-free and disease-specific survival across FIGO grades. Similar findings were also seen when a binary grading system was utilized. Since FIGO grade was not associated with survival, we conclude that the intrinsic biology of these tumors, characterized by their molecular profile, may override the significance of FIGO grading.

Integration of clinical sequencing and immunohistochemistry for the molecular classification of endometrial carcinoma

PURPOSE

Using next generation sequencing (NGS), The Cancer Genome Atlas (TCGA) found that endometrial carcinomas (ECs) fall under one of four molecular subtypes, and a POLE mutation status, mismatch repair (MMR) and p53 immunohistochemistry (IHC)-based surrogate has been developed. We sought to retrospectively classify and characterize a large series of unselected ECs that were prospectively subjected to clinical sequencing by utilizing clinical molecular and IHC data.

EXPERIMENTAL DESIGN

All patients with EC with clinical tumor-normal MSK-IMPACT NGS from 2014 to 2020 (n = 2115) were classified by integrating molecular data (i.e., POLE mutation, TP53 mutation, MSIsensor score) and MMR and p53 IHC results. Survival analysis was performed for primary EC patients with upfront surgery at our institution.

RESULTS

Utilizing our integrated approach, significantly more ECs were molecularly classified (1834/2115, 87%) as compared to the surrogate (1387/2115, 66%, p < 0.001), with an almost perfect agreement for classifiable cases (Kappa 0.962, 95% CI 0.949-0.975). Discrepancies were primarily due to TP53 mutations in p53-IHC-normal ECs. Of the 1834 ECs, most were of copy number (CN)-high molecular subtype (40%), followed by CN-low (32%), MSI-high (23%) and POLE (5%). Histologic and genomic variability was present amongst all molecular subtypes. Molecular classification was prognostic in early- and advanced-stage disease, including early-stage endometrioid EC.

CONCLUSIONS

The integration of clinical NGS and IHC data allows for an algorithmic approach to molecularly classifying newly diagnosed EC, while overcoming issues of IHC-based genetic alteration detection. Such integrated approach will be important moving forward given the prognostic and potentially predictive information afforded by this classification.

A case of solitary lymph node recurrence 9 years after initial treatment for advanced premenopausal endometrioid endometrial cancer; clinical usefulness of hormonal replacement therapy

There is no consensus on the use of hormone replacement therapy (HRT) after treatment of advanced corpus cancer. We report a case of advanced corpus cancer at a young age, in which HRT was initiated 7 years after surgery, and regional lymph node recurrence was later detected. The patient was 35 years old at the time of initial treatment in X year, when she was diagnosed with stageIIIC2 corpus cancer and underwent a hysterectomy with bilateral salpingo-oophorectomy and a retroperitoneal lymphadenectomy. HRT was started at X + 7 years, and at X + 9 years, a 25 × 12-mm-sized mass was found in the hilum of the right kidney. A laparoscopic resection revealed regional lymph node recurrence of the corpus cancer. A retrospective study further revealed that a tumor measuring 12 × 3 mm was found at X + 3 years and grew to 18 × 7 mm in X + 6 years, just before the start of the HRT. We hypothesize that HRT did not induce tumor recurrence; instead, it allowed for long-term follow-up and early diagnosis.

Comprehensive analysis of germline drivers in endometrial cancer

BACKGROUND

We sought to determine the prevalence of germline pathogenic variants (gPVs) in unselected patients with endometrial cancer (EC), define biallelic gPVs within tumors, and describe their associations with clinicopathologic features.

METHODS

Germline assessment of at least 76 cancer predisposition genes was performed in patients with EC undergoing clinical tumor-normal Memorial Sloan Kettering-Integrated Mutation Profiling of Actionable Cancer Targets (MSK-IMPACT) sequencing from January 1, 2015, to June 30, 2021. In patients with gPVs, biallelic alterations in ECs were identified through analysis of loss of heterozygosity and somatic PVs. Clinicopathologic variables were compared using nonparametric tests.

RESULTS

Of 1625 patients with EC, 216 (13%) had gPVs, and 15 patients had 2 gPVs. There were 231 gPVs in 35 genes (75 [32%] high penetrance; 39 [17%] moderate penetrance; and 117 [51%] low, recessive, or uncertain penetrance). Compared with those without gPVs, patients with gPVs were younger (P = .002), more often White (P = .009), and less obese (P = .025) and had differences in distribution of tumor histology (P = .017) and molecular subtype (P < .001). Among 231 gPVs, 74 (32%) exhibited biallelic inactivation within tumors. For high-penetrance gPVs, 63% (47 of 75) of ECs had biallelic alterations, primarily affecting mismatch repair (MMR) and homologous recombination related genes, including BRCA1,BRCA2, RAD51D, and PALB2. Biallelic inactivation varied across molecular subtypes with highest rates in microsatellite instability-high (MSI-H) or copy-number (CN)-high subtypes (3 of 12 [25%] POLE, 30 of 77 [39%] MSI-H, 27 of 60 [45%] CN-high, 9 of 57 [16%] CN-low; P < .001).

CONCLUSIONS

Of unselected patients with EC, 13% had gPVs, with 63% of gPVs in high-penetrance genes (MMR and homologous recombination) exhibiting biallelic inactivation, potentially driving cancer development. This supports germline assessment in EC given implications for treatment and cancer prevention.

Corded and hyalinized endometrioid carcinoma: Summary of clinical, histological, immunohistochemical and molecular data

Corded and hyalinized endometrioid carcinoma (CHEC) represents a potential pitfall for pathologists. This study aimed to provide a complete overview of all clinicopathological and molecular features of CHEC. Electronic databases were searched for all published series of CHEC. Clinical, histological, immunohistochemical and molecular data about CHEC were extracted and pooled. Six studies with 62 patients were identified; mean age was 49.8 years (range 19-83). Most cases showed FIGO stage I (68%), low grade (87.5%), and a favorable outcome (78.4%), with "no specific molecular profile" (NSMP). A subset of cases showed high-grade features (12.5%), p53 abnormalities (11.1%) or mismatch repair (MMR) deficiency (20%) and occurred at an older age (mean age>60 years). Common features of CHEC were: superficial localization of the corded component (88.6%), squamous/morular differentiation (82.5%), nuclear β-catenin accumulation (92%), partial/total loss of CKAE1/AE3 (88.9%), estrogen receptor (95.7%) and e-cadherin (100%), stromal changes such as myxoid (38.5%), osteoid (24%) and chondroid (4.5%), CTNNB1 mutations (57.9%), and POLE-wild-type (100%); 24.4% of cases showed lymphovascular space invasion. A minority of cases (16.2%) showed poor outcome despite a low-grade, NSMP phenotype; the molecular basis for the aggressiveness of these cases is still undefined. Further studies are necessary in this field.

Prognostic Impact of Pathologic Features in Molecular Subgroups of Endometrial Carcinoma

The molecular characterization of endometrial carcinoma (EC) has recently been included in the ESGO/ESTRO/ESP guidelines. The study aims to evaluate the impact of integrated molecular and pathologic risk stratification in the clinical practice and the relevance of pathologic parameters in predicting prognosis in each EC molecular subgroup. ECs were classified using immunohistochemistry and next-generation sequencing into the four molecular classes: POLE mutant (POLE), mismatch repair deficient (MMRd), p53 mutant (p53abn), and no specific molecular profile (NSMP). According to the WHO algorithm, 219 ECs were subdivided into the following molecular subgroups: 7.8% POLE, 31% MMRd, 21% p53abn, 40.2% NSMP. Molecular classes as well as ESGO/ESTRO/ESP 2020 risk groups were statistically correlated with disease-free survival. Considering the impact of histopathologic features in each molecular class, stage was found to be the strongest prognostic factor in MMRd ECs, whereas in the p53abn subgroup, only lymph node status was associated with recurrent disease. Interestingly, in the NSMP tumor, several histopathologic features were correlated with recurrence: histotype, grade, stage, tumor necrosis, and substantial lymphovascular space invasion. Considering early-stage NSMP ECs, substantial lymphovascular space invasion was the only independent prognostic factor. Our study supports the prognostic importance of EC molecular classification and demonstrated the essential role of histopathologic assessment in patients' management.

Impact of immune infiltration signatures on prognosis in endometrial carcinoma is dependent on the underlying molecular subtype

OBJECTIVES

Increased numbers of tumor infiltrating lymphocytes (TIL) in endometrial cancer (EC) are associated with improved survival, but it is unclear how this prognostic significance relates to the underlying EC molecular subtype. In this explorative hypothesis-generating study, we sought to define the immune signatures associated with the molecular subtypes of EC (i.e., POLE-mutated, microsatellite unstable (MSI-high), copy number (CN)-low, and CN-high) and to determine their correlation with patient outcomes.

METHODS

RNA-sequencing and molecular subtype data of 232 primary ECs were obtained from The Cancer Genome Atlas. Deconvolution of bulk gene expression data was performed using single sample Gene Set Enrichment Analysis (ssGSEA) and Cell type Identification By Estimating Relative Subsets Of known RNA Transcripts (CIBERSORT). The association of the resultant immune signatures with overall survival was determined across molecular subtypes.

RESULTS

Statistically significant differences in enrichment were identified in 16/30 and 6/23 immune gene sets by ssGSEA and CIBERSORT, respectively. Signature of CD8+ cells in ECs of CN-high molecular subtype was associated with improved overall survival by ssGSEA (p = 0.0108), while CD8 signatures did not appear to be prognostic in MSI-high (p = 0.74) or CN-low EC molecular subtypes (p = 0.793). Of all molecular subtypes, CN-high ECs exhibited the lowest levels of CD8+ T cell infiltration. Consistent with antigen-induced T cell activation and exhaustion, enrichment for immunomodulatory receptors was predominantly observed in ECs of MSI-high and POLE-mutated molecular subtypes.

CONCLUSIONS

Deconvolution of bulk gene expression data can be used to identify populations of immune infiltrated endometrial cancers with improved survival. These data support the existence of unique mechanisms of immune resistance within molecular subgroups of the disease.

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.

Molecular Landscape of Mullerian Clear Cell Carcinomas Identifies The Cancer Genome Atlas-like Prognostic Subgroups

Mullerian clear cell carcinoma (CCC) is often aggressive and chemoresistant. The prognostic significance of molecular subclassification of endometrioid carcinomas is well established. However, less is known about the molecular landscape of CCC. The aim of this study was to better characterize the genetic landscape of a large cohort of CCC and correlate these findings with clinicopathologic features. CCC of the ovary (n = 72), endometrium (n = 24), and peritoneum/abdominal wall (n = 5) were retrospectively identified. Tumors had undergone tumor-only targeted sequencing using a hybrid capture next-generation sequencing panel. Median tumor mutational burden was 6.8 mutations/megabase (range, 1.3-185, 21% were ≥10 mutations/Mb). The most frequently mutated genes were ARID1A (48%), PIK3CA (45%), TP53 (23%), and PTEN (10%). ERBB2 amplification occurred in 4%. When classified according to the Cancer Genome Atlas/the Proactive Molecular Risk Classifier for Endometrial Cancer endometrial carcinoma molecular subgroups, 3 (3%) were POLE ultramutated, 5 (5%) were microsatellite instability-high (MSI-H), 20 (20%) were TP53-mutant subgroup, and 73 (72%) were no specific molecular profile (NSMP). Immunohistochemical expression of estrogen receptor, progesterone receptor, and programmed death-ligand 1 were not associated with the molecular subgroup. POLE and MSI-H tumors were characterized by an excellent prognosis, and the TP53-mutant subgroup had a worse disease-free survival than NSMP. NSMP tumors could be further substratified as high-risk NSMP if they lacked PIK3CA, PIK3R1, and ARID1A mutations, and/or harbored a TERT-promoter mutation. The Cancer Genome Atlas and NSMP-specific stratifications were prognostic for both the entire cohort and the subset of stage I ovarian tumors. On multivariable analysis, stage, lymphovascular invasion, and tumor mutational burden were prognostic for disease-free survival, whereas advanced stage and TP53-mutant subgroup - but not a TP53 mutation in isolation - were negative prognostic factors for overall survival. These data suggest that routine molecular profiling of Mullerian CCC may be warranted for both prognosis and identification of potential targeted treatments, such as immunotherapy and anti-HER2 agents.

Grade and Estrogen Receptor Expression Identify a Subset of No Specific Molecular Profile Endometrial Carcinomas at a Very Low Risk of Disease-Specific Death

Endometrial carcinoma (EC) can be divided into 4 prognostic molecular subtypes, and no specific molecular profile (NSMP) type is the most commonly occurring type (∼50%). Although described as having an intermediate to favorable prognosis, this subtype encompasses pathologically and molecularly diverse tumors. We aimed to identify factors associated with outcomes within the NSMP ECs that might be used to stratify prognosis and direct treatment. Clinicopathologic, immunohistochemical, and genetic features of a large series of NSMP EC were used to identify parameters that could identify the subset associated with a very favorable outcome (disease-specific death rate <5% at 5 years, termed low-risk NSMP). A total of 1110 NSMP ECs were profiled. In a univariate analysis, stage, grade, lymphovascular invasion, estrogen receptor (ER) and progesterone receptor (PR) expression, L1CAM overexpression, and mutations in PIK3CA were associated with disease-specific survival. Two critical features, grade and ER expression, identified a low-risk NSMP subset (grade 1-2, ER-positive [>1%], 84% of cases), which showed a 5-year disease-specific death rate of 1.6% across all stages and 1.4% within stage I. The remaining cases (high-risk NSMPs, grade 3, and/or ER-negative status) were responsible for most of the disease-specific deaths (disease-specific death rate at 5 years, 22.9%; hazard ratio compared with that of low-risk NSMPs: 16.3; 95% CI, 8.4-31.7). Within NSMP EC, the low-risk and high-risk categories were of prognostic significance independent of the stage on a multivariate analysis. Low-grade and ER-positive NSMP ECs are a homogeneous low-risk group associated with an exceptionally favorable prognosis in which de-escalation and/or endocrine therapy strategies can be applied. Grade 3 and/or ER-negative status identifies a high-risk NSMP subset, including rare high-grade histotypes (eg, clear cell, dedifferentiated, and mesonephric-like), responsible for most NSMP-related deaths. Subclassification of NSMPs allows for the category of low-risk EC molecular subtypes to be dramatically expanded because it now includes both POLEmut and the much more common low-risk NSMP EC.

Prognostic refinement of NSMP high-risk endometrial cancers using oestrogen receptor immunohistochemistry

BACKGROUND

Risk-assessment of endometrial cancer (EC) is based on clinicopathological factors and molecular subgroup. It is unclear whether adding hormone receptor expression, L1CAM expression or CTNNB1 status yields prognostic refinement.

METHODS

Paraffin-embedded tumour samples of women with high-risk EC (HR-EC) from the PORTEC-3 trial (n = 424), and a Dutch prospective clinical cohort called MST (n = 256), were used. All cases were molecularly classified. Expression of L1CAM, ER and PR were analysed by whole-slide immunohistochemistry and CTNNB1 mutations were assessed with a next-generation sequencing. Kaplan-Meier method, log-rank tests and Cox's proportional hazard models were used for survival analysis.

RESULTS

In total, 648 HR-EC were included. No independent prognostic value of ER, PR, L1CAM, and CTNNB1 was found, while age, stage, and adjuvant chemotherapy had an independent impact on risk of recurrence. Subgroup-analysis showed that only in NSMP HR-EC, ER-positivity was independently associated with a reduced risk of recurrence (HR 0.33, 95%CI 0.15-0.75).

CONCLUSIONS

We confirmed the prognostic impact of the molecular classification, age, stage, and adjuvant CTRT in a large cohort of high-risk EC. ER-positivity is a strong favourable prognostic factor in NSMP HR-EC and identifies a homogeneous subgroup of NSMP tumours. Assessment of ER status in high-risk NSMP EC is feasible in clinical practice and could improve risk stratification and treatment.

Integration of Molecular Data in the Prognostic Stratification and Management of Endometrial Carcinoma

In the last years, the TCGA-based molecular classifier have been progressively integrated in the management of endometrial carcinoma. While molecular assays are increasingly available across pathology laboratories, the additional costs will expectedly be compensated by a reduction in overtreatments and a prevention of recurrences. The additional time might be shortened by assessing molecular markers on biopsy specimens. Retrospective data suggest that the molecular classifier will have a major impact of on the risk stratification, with many patients having their risk class down- or upstaged based on POLE mutations or p53 abnormalities, respectively. However, there are still several issues to be resolved, such as the prognostic value of the TCGA classifier in each FIGO stage, or the type of adjuvant treatment most suitable for each molecular group. Other issues regard the prognostic stratification of the mismatch repair-deficient and "no specific molecular profile" groups, which currently follows the same criteria; however, the former seems to be prognostically consistent regardless of FIGO grade and histotype, whereas the latter appears highly heterogeneous. Numerous clinical, histological, immunohistochemical and molecular markers have been proposed to refine the TCGA classification, but their prognostic value is still undefined. Hopefully, prospective data collected in the next years will help resolving these issues.

Gastric-type adenocarcinoma of the cervix: Clinical outcomes and genomic drivers

OBJECTIVES

Gastric-type endocervical adenocarcinoma (GEA) is a rare form of cervical cancer not associated with human papilloma virus (HPV) infection. We summarize our experience with GEA at a large cancer center.

METHODS

Clinical and demographic information on all patients diagnosed with GEA between June 1, 2002 and July 1, 2019 was obtained retrospectively from clinical charts. Kaplan-Meier survival analysis was performed to describe progression-free survival (PFS) and overall survival (OS). Tumors from a subset of patients underwent next generation sequencing (NGS) analysis.

RESULTS

A total of 70 women with GEA were identified, including 43 who received initial treatment at our institution: of these 4 (9%) underwent surgery alone, 15 (35%) underwent surgery followed by adjuvant therapy, 10 (23%) were treated with definitive concurrent chemoradiation (CCRT), 7 (16%) with chemotherapy alone, and 3 (7%) with neoadjuvant CCRT and hysterectomy with or without chemotherapy. One-third (n = 14) of patients experienced disease progression, of whom 86% (n = 12) had prior CCRT. The median PFS and OS for patients with stage I GEA were 107 months (95% CI 14.8-199.2 months) and 111 months (95% CI 17-205.1 months) respectively, compared to 17 months (95% CI 5.6-28.4 months) and 33 months (95% CI 28.2-37.8 months) for patients with stages II-IV, respectively. On NGS, 4 patients (14%) had ERBB2 alterations, including 2 patients who received trastuzumab.

CONCLUSIONS

GEA is an aggressive form of cervical cancer with poor PFS and OS when diagnosed at stage II or later. Further investigation is needed to identify the optimal management approach for this rare subtype.

TCGA Molecular Prognostic Groups of Endometrial Carcinoma: Current Knowledge and Future Perspectives

The four TCGA-based molecular prognostic groups of endometrial carcinoma (EC), i.e., POLE-mutant, mismatch repair (MMR)-deficient, p53-abnormal, and “no specific molecular profile” (NSMP), have recently been integrated into ESGO-ESTRO-ESP guidelines. The POLE-mutant and MMR-deficient groups are associated with high mutational load, morphological heterogeneity, and inflammatory infiltration. These groups are frequent in high-grade endometrioid, undifferentiated/dedifferentiated, and mixed histotypes. POLE-mutant ECs show good prognosis and do not require adjuvant treatment, although the management of cases at stage >II is still undefined. MMR-deficient ECs show intermediate prognosis and are currently substratified based on clinicopathological variables, some of which might not have prognostic value. These groups may benefit from immunotherapy. P53-mutant ECs are typically high-grade and often morphologically ambiguous, accounting for virtually all serous ECs, most carcinosarcomas and mixed ECs, and half of clear-cell ECs. They show poor prognosis and are treated with chemoradiotherapy; a subset may benefit from HER2 inhibitors or PARP inhibitors. The NSMP group is the most frequent TCGA group; its prognosis is highly variable and affected by clinicopathological/molecular factors, most of which are still under evaluation. In conclusion, the TCGA classification has improved diagnosis, risk stratification, and management of EC. Further studies are needed to resolve the points of uncertainty that still exist.

Endometrial Carcinoma: Molecular Cytogenetics and Transcriptomic Profile

Endometrial carcinomas (ECs) are histologically classified as endometrioid and nonendometrioid tumors, with each subgroup displaying different molecular profiles and clinical outcomes. Considerable biological and clinical heterogeneity exists within this scheme, however, reflecting its imperfection. We aimed to gather additional data that might help clarify the tumors’ pathogenesis and contribute toward a more meaningful classification scheme. In total, 33 ECs were examined for the presence of chromosomal aberrations, genomic imbalances, pathogenic variants, microsatellite instability, and expression profiles at both gene and miRNA levels. Chromosome 1 was the most frequently rearranged chromosome, showing a gain of all or part of the long arm. Pathogenic variants were found for PTEN (53%), PDGFRA (37%), PIK3CA (34%), and KIT (31%). High microsatellite instability was identified in 15 ECs. Comparing tumors and controls, we identified 23 differentially expressed genes of known importance in carcinogenesis, 15 genes involved in innate and adaptative immune responses, and altered expression of 7 miRNAs. miR-32-5p was the most upregulated. Our series showed a high degree of heterogeneity. Tumors were well-separated from controls, but there was no clear-cut separation between endometrioid and nonendometrioid ECs. Whether this means that the current phenotypic classification is of little relevance or if one still has not detected which genomic parameters to enter into correlation analyses remains unknown.

Genomic Determinants of Early Recurrences in Low-Stage, Low-Grade Endometrioid Endometrial Carcinoma

Low-stage, low-grade endometrioid endometrial carcinoma (EEC), the most common histologic type of endometrial cancer, typically has a favorable prognosis. A subset of these cancers, however, displays an aggressive clinical course with early recurrences, including distant relapses. All statistical tests were 2-sided. Using a combination of whole-exome and targeted capture sequencing of 65 FIGO stage IA and IB grade 1 EECs treated with surgery alone, we demonstrate that chromosome 1q gain (odds ratio [OR] = 8.09, 95% confidence interval [CI] = 1.59 to 54.6; P = .02), PIK3CA mutation (OR = 9.16, 95% CI = 1.95 to 61.8; P = .01), and DNA mismatch repair-deficient molecular subtype (OR = 7.92, 95% CI = 1.44 to 87.6; P = .02) are independent predictors of early recurrences within 3 years in this patient population. Chromosome 1q gain was validated in an independent dataset of stage I grade 1 EECs subjected to whole-exome sequencing. Our findings expand on the repertoire of genomic parameters that should be considered in the evaluation of patients with low-stage, low-grade EEC.