Postoperative radiotherapy for International Federation of Gynaecology and Obstetrics (FIGO) stage-1 endometrial carcinoma is a subject of controversy due to the low relapse rate and the lack of data from randomised trials. We did a multicentre prospective randomised trial to find whether postoperative pelvic radiotherapy improves locoregional control and survival for patients with stage-1 endometrial carcinoma.Patients with stage-1 endometrial carcinoma (grade 1 with deep [> or =50%] myometrial invasion, grade 2 with any invasion, or grade 3 with superficial [<50%] invasion) were enrolled. After total abdominal hysterectomy and bilateral salpingo-oophorectomy, without lymphadenectomy, 715 patients from 19 radiation oncology centres were randomised to pelvic radiotherapy (46 Gy) or no further treatment. The primary study endpoints were locoregional recurrence and death, with treatment-related morbidity and survival after relapse as secondary endpoints.Analysis was done according to the intention-to-treat principle. Of the 715 patients, 714 could be evaluated. The median duration of follow-up was 52 months. 5-year actuarial locoregional recurrence rates were 4% in the radiotherapy group and 14% in the control group (p<0.001). Actuarial 5-year overall survival rates were similar in the two groups: 81% (radiotherapy) and 85% (controls), p=0.31. Endometrial-cancer-related death rates were 9% in the radiotherapy group and 6% in the control group (p=0.37). Treatment-related complications occurred in 25% of radiotherapy patients, and in 6% of the controls (p<0.0001). Two-thirds of the complications were grade 1. Grade 3-4 complications were seen in eight patients, of which seven were in the radiotherapy group (2%). 2-year survival after vaginal recurrence was 79%, in contrast to 21% after pelvic recurrence or distant metastases. Survival after relapse was significantly (p=0.02) better for patients in the control group. Multivariate analysis showed that for locoregional recurrence, radiotherapy and age below 60 years were significant favourable prognostic factors.Postoperative radiotherapy in stage-1 endometrial carcinoma reduces locoregional recurrence but has no impact on overall survival. Radiotherapy increases treatment-related morbidity. Postoperative radiotherapy is not indicated in patients with stage-1 endometrial carcinoma below 60 years and patients with grade-2 tumours with superficial invasion.

Recommendations for adjuvant treatment for women with early-stage endometrial carcinoma are based on clinicopathologic features. Comprehensive genomic characterization defined four subgroups: p53-mutant, microsatellite instability (MSI), POLE-mutant, and no specific molecular profile (NSMP). We aimed to confirm the prognostic capacity of these subgroups in large randomized trial populations, investigate potential other prognostic classifiers, and integrate these into an integrated molecular risk assessment guiding adjuvant therapy.Analysis of MSI, hotspot mutations in 14 genes including POLE, protein expression of p53, ARID1a, β-catenin, L1CAM, PTEN, ER, and PR was undertaken on 947 available early-stage endometrioid endometrial carcinomas from the PORTEC-1 and -2 trials, mostly high-intermediate risk (n = 614). Prognostic value was determined using univariable and multivariable Cox proportional hazard models. AUCs of different risk stratification models were compared.Molecular analyses were feasible in >96% of the patients and confirmed the four molecular subgroups: p53-mutant (9%), MSI (26%), POLE-mutant (6%), and NSMP (59%). Integration of prognostic molecular alterations with established clinicopathologic factors resulted in a stronger model with improved risk prognostication. Approximately 15% of high-intermediate risk patients had unfavorable features (substantial lymphovascular space invasion, p53-mutant, and/or >10% L1CAM), 50% favorable features (POLE-mutant, NSMP being microsatellite stable, and CTNNB1 wild-type), and 35% intermediate features (MSI or CTNNB1-mutant).Integrating clinicopathologic and molecular factors improves the risk assessment of patients with early-stage endometrial carcinoma. Assessment of this integrated risk profile is feasible in daily practice, and holds promise to reduce both overtreatment and undertreatment. Clin Cancer Res; 22(16); 4215-24. ©2016 AACR.©2016 American Association for Cancer Research.

A European consensus conference on endometrial carcinoma was held in 2014 to produce multi-disciplinary evidence-based guidelines on selected questions. Given the large body of literature on the management of endometrial carcinoma published since 2014, the European Society of Gynaecological Oncology (ESGO), the European SocieTy for Radiotherapy and Oncology (ESTRO), and the European Society of Pathology (ESP) jointly decided to update these evidence-based guidelines and to cover new topics in order to improve the quality of care for women with endometrial carcinoma across Europe and worldwide.© IGCS and ESGO 2021. No commercial re-use. See rights and permissions. Published by BMJ.

Endometrial carcinomas can be classified into four molecular subgroups - mismatch repair deficient (MMRd), p53 abnormal (p53abn), polymerase-ϵ () ultramutated, and 'no specific molecular profile' (NSMP). Retrospective data imply that the response to adjuvant therapies may depend on the molecular subgroup. These findings emphasize the need for adjuvant therapy trials where patients are randomized to treatment arms separately within each molecular subgroup.The PErsonalized TReatment for Endometrial Carcinoma (PETREC) trial clarifies the value of molecular classification in the determination of adjuvant therapies of high-intermediate risk and early-stage high-risk endometrial carcinoma.Compared with vaginal brachytherapy, the utilization of whole pelvic radiotherapy may result in improved outcomes for either MMRd or NSMP high-intermediate risk carcinomas. Early-stage high-risk p53abn and nonendometrioid carcinomas are postulated to gain benefits from chemoradiotherapy, as opposed to chemotherapy alone. ultramutated carcinomas harboring high-intermediate or high-risk clinicopathologic features are speculated to have favorable prognosis without any adjuvant therapy.This prospective, multicenter, phase 3 trial compares the efficacy of vaginal brachytherapy vs whole pelvic radiotherapy in high-intermediate risk MMRd and NSMP molecular subgroups, and chemotherapy vs chemoradiotherapy in early-stage high-risk p53abn subtype and nonendometrioid carcinomas. Eligible women who consent to participation in the trial are randomly allocated (1:1) to treatment arms.Women with stages I-II molecular integrated high-intermediate risk or high-risk endometrial carcinoma will be included.The primary endpoint is the 5 year cumulative incidence of disease recurrence.A total sample size of 294 patients (49 subjects in each treatment arm of the three subgroups intended for randomization) was estimated to be sufficient.Patient recruitment will be completed in 2025, and follow-up will be completed in 2030.NCT05655260.© IGCS and ESGO 2023. No commercial re-use. See rights and permissions. Published by BMJ.

The NCCN Guidelines for Uterine Neoplasms provide recommendations for diagnostic workup, clinical staging, and treatment options for patients with endometrial cancer and uterine sarcoma. The NCCN Cervical Uterine Panel meets at least annually to review comments from reviewers within their institutions; examine relevant new data from publications, abstracts, and recent FDA approvals; and reevaluate and update recommendations. These NCCN Guidelines Insights summarize the panel’s deliberations on the new FIGO 2023 staging system and updates on the new systemic therapy recommendations for the management of endometrial cancer.

The US Food and Drug Administration (FDA) approved immune checkpoint inhibitor therapy for patients with advanced solid tumors that have DNA mismatch repair defects or high levels of microsatellite instability; however, the FDA provided no guidance on which specific clinical assays should be used to determine mismatch repair status.To develop an evidence-based guideline to identify the optimal clinical laboratory test to identify defects in DNA mismatch repair in patients with solid tumor malignancies who are being considered for immune checkpoint inhibitor therapy.The College of American Pathologists convened an expert panel to perform a systematic review of the literature and develop recommendations. Using the National Academy of Medicine-endorsed Grading of Recommendations Assessment, Development and Evaluation approach, the recommendations were derived from available evidence, strength of that evidence, open comment feedback, and expert panel consensus. Mismatch repair immunohistochemistry, microsatellite instability derived from both polymerase chain reaction and next-generation sequencing, and tumor mutation burden derived from large panel next-generation sequencing were within scope.Six recommendations and 3 good practice statements were developed. More evidence and evidence of higher quality were identified for colorectal cancer and other cancers of the gastrointestinal (GI) tract than for cancers arising outside the GI tract.An optimal assay depends on cancer type. For most cancer types outside of the GI tract and the endometrium, there was insufficient published evidence to recommend a specific clinical assay. Absent published evidence, immunohistochemistry is an acceptable approach readily available in most clinical laboratories.© 2022 College of American Pathologists.

\n The 2013 Cancer Genome Atlas (TCGA) study identified four molecular types of endometrial carcinoma (EC) that are prognostic and predictive of therapy response. The p53 abnormal (p53abn) group of tumours is associated with aggressive clinical behaviour, chemoresponsiveness and generally high‐grade histology. p53abn tumours may be identified by p53 immunohistochemical staining (a surrogate marker) or molecular testing. In this study, we evaluated the concordance between p53 immunohistochemistry and\n TP53\n molecular testing in a consecutive cohort of ECs from a population‐based setting. Our aim was to investigate the rate of concordance and reasons for discordance between the immunohistochemistry and molecular testing and to provide recommendations for pathologists and clinicians dealing with these discordant cases.\n

For patients with endometrial cancer, the POLE (polymerase epsilon) mutation (POLEmut)‐subtype, one of four molecular‐analysis‐based categories in the Cancer Genome Atlas (TCGA), has the best prognosis. The following histological characteristics are typically observed in endometroid carcinoma cases with the POLEmut‐subtype: (1) the presence of tumour giant cells, (2) numerous tumour‐infiltrating lymphocytes (TILs) and/or peri‐tumoral lymphocytes, and (3) a high grade. However, in the context of cytology, the morphological characteristics of this subtype remain unknown.

Endometrial Cancer (EC) is still a challenge for gynecological oncologists because the treatment of the advanced disease remains an unmet need for patients. The Cancer Genome Atlas Research Network (TCGA) recently provided a comprehensive genomic and transcriptomic analysis of EC, offering a new classification of the disease, based on genetic features, which defines four subgroups of cancer rather than the two traditionally recognized. In the molecular classification two types of EC, the polymerase epsilon (POLE)-ultramutated and the microsatellite instability (MSI)-hypermutated, seem to present an enhanced immune microenvironment and a high mutation burden. The blockade of the immune checkpoints is an innovative approach that has largely demonstrated to be effective in solid malignancies, such as lung, renal and melanoma; it acts by reducing the cancer-induced immune-suppression through inhibition of the PD-1/PD-L1 (Programmed Death and PD-Ligand) axis. All available evidence supporting an over-expression of the PD-1/PD-L1 pathway in EC has been reviewed. In particular in the POLE and MSI ECs an up-regulation of this pathway was found, aiming to suggest a rationale for testing the PD-1/PD-L1 immunotherapy in these cancer subgroups. Copyright © 2016 Elsevier Ltd. All rights reserved.

Pembrolizumab plus chemotherapy provides clinically meaningful benefit as first-line therapy for advanced (locoregional extension and residual disease after surgery)/metastatic/recurrent mismatch repair-proficient (pMMR) and mismatch repair-deficient (dMMR) endometrial cancer, with greater magnitude of benefit in the dMMR phenotype. We evaluated the addition of pembrolizumab to adjuvant chemotherapy (with/without radiation therapy) among patients with newly diagnosed, high-risk endometrial cancer without any residual macroscopic disease following curative-intent surgery.We included patients with histologically confirmed high-risk [International Federation of Gynecology and Obstetrics (FIGO) stage I/II of non-endometrioid histology or endometrioid histology with p53/TP53 abnormality, or stage III/IVA of any histology] endometrial cancer following surgery with curative intent and no evidence of disease postoperatively, with no prior radiotherapy or systemic therapy. Patients were randomised to pembrolizumab 200 mg or placebo every 3 weeks (Q3W) for six cycles added to carboplatin-paclitaxel followed by pembrolizumab 400 mg or placebo every 6 weeks (Q6W) for six cycles per treatment assignment. Radiotherapy was at the investigator's discretion. The primary endpoints were investigator-assessed disease-free survival (DFS) and overall survival in the intention-to-treat population.A total of 1095 patients were randomised (pembrolizumab, n = 545; placebo, n = 550). At this interim analysis (data cut-off, 4 March 2024), 119 (22%) DFS events occurred in the pembrolizumab group and 121 (22%) occurred in the placebo group [hazard ratio 1.02, 95% confidence interval (CI) 0.79-1.32; P = 0.570]. Kaplan-Meier estimates of 2-year DFS rates were 75% and 76% in the pembrolizumab and placebo groups, respectively. The hazard ratio for DFS was 0.31 (95% CI 0.14-0.69) in the dMMR population (n = 281) and 1.20 (95% CI 0.91-1.57) in the pMMR population (n = 814). Grade ≥3 adverse events (AEs) occurred in 386 of 543 (71%) and 348 of 549 (63%) patients in the pembrolizumab and placebo groups, respectively. No treatment-related grade 5 AEs occurred.Adjuvant pembrolizumab plus chemotherapy did not improve DFS in patients with newly diagnosed, high-risk, all-comer endometrial cancer. Preplanned subgroup analyses for stratification factors suggest that pembrolizumab plus chemotherapy improved DFS in patients with dMMR tumours. Safety was manageable.ClinicalTrials.gov, NCT04634877; EudraCT, 2020-003424-17.Merck Sharp & Dohme LLC, a subsidiary of Merck & Co., Inc., Rahway, NJ, USA.Copyright © 2024 Merck Sharp & Dohme LLC, a subsidiary of Merck & Co., Inc., Rahway, NJ, USA., The Author(s). Published by Elsevier Ltd.. All rights reserved.

Classification of endometrial carcinomas (ECs) by morphologic features is irreproducible and imperfectly reflects tumor biology. The authors developed the Proactive Molecular Risk Classifier for Endometrial Cancer (ProMisE), a molecular classification system based on The Cancer Genome Atlas genomic subgroups, and sought to confirm both feasibility and prognostic ability in a new, large cohort of ECs.Immunohistochemistry (IHC) for the presence or absence of mismatch repair (MMR) proteins (to identify MMR deficiency [MMR-D]), sequencing for polymerase-ɛ (POLE) exonuclease domain mutations (POLE EDMs), and IHC for tumor protein 53 (p53) (wild type vs null/missense mutations; p53 wt and p53 abn, respectively) were performed on 319 new EC samples. Subgroups were characterized and assessed relative to outcomes. The prognostic ability of ProMisE was compared with that of current risk-stratification systems (European Society of Medical Oncology [ESMO]).ProMisE decision-tree classification achieved categorization of all cases and identified 4 prognostic subgroups with distinct overall, disease-specific, and progression-free survival (P < .001). Tumors with POLE EDMs had the most favorable prognosis, and those with p53 abn the worst prognosis, and separation of the 2 middle survival curves (p53 wt and MMR-D) was observed. There were no significant differences in survival between the ESMO low-risk and intermediate-risk groups. ProMisE improved the ability to discriminate outcomes compared with ESMO risk stratification. There was substantial overlap (89%) between the p53 abn and high-risk ESMO subgroups; but, otherwise, there were no predictable associations between molecular and ESMO risk groups.Molecular classification of ECs can be achieved using clinically applicable methods and provides independent prognostic information beyond established clinicopathologic risk factors available at diagnosis. Consistent, biologically relevant categorization enables stratification for clinical trials and/or targeted therapy, identification of women who are at increased risk of having Lynch syndrome, and may guide clinical management. Cancer 2017;123:802-13. © 2016 American Cancer Society.© 2017 American Cancer Society.

To assess the risk stratification of clinicopathologically and molecularly classified endometrial cancer based on estrogen receptor (ER) and L1 cell adhesion molecule (L1CAM) expression.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.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).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.Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.

Endometrial endometrioid carcinomas (EECs) with exon 3 CTNNB1 mutations characterize a more aggressive subset of tumors in patients with low-grade low-stage disease. Thus, prospectively identifying these cases may be clinically relevant. The aim of this study was to examine the feasibility of β-catenin and Cyclin D1 immunohistochemistry to identify EECs harboring CTNNB1 mutations and to evaluate the clinicopathologic features of EECs with exon 3 CTNNB1 mutations. Thirty-nine CTNNB1 mutated EECs and 40 CTNNB1 wild-type EECs were identified from a cohort of previously sequenced endometrial carcinomas using a targeted next-generation sequencing panel. Immunohistochemistry for β-catenin and Cyclin D1 was performed on all cases. Immunohistochemistry results were correlated with CTNNB1 mutation status and clinicopathologic parameters. Patients with CTNNB1 mutated EECs were younger than those with CTNNB1 wild-type (56.2 vs. 61.5 y; P=0.033). Nuclear β-catenin expression correlated with exon 3 CTNNB1 mutation (P<0.0001) with a sensitivity of 91% and a specificity of 89%. Cyclin D1 expression correlated with CTNNB1 exon 3 mutation with relatively high specificity (90%) but low sensitivity (29%). Recurrence rate in patients with stage IA disease at diagnosis was significantly higher in patients whose tumors were CTNNB1 mutated compared with CTNNB1 wild-type (30% vs. 0%; P=0.025) and included distant metastases; all recurrent tumors in this group harbored exon 3 mutations and were histologically low grade (5 grade 1, 2 grade 2). Nuclear β-catenin expression appears to be an acceptable proxy for CTNNB1 mutation.

In this study, we aimed to evaluate the prognostic impact of molecular alterations beyond those included in the Proactive Molecular Risk Classifier for Endometrial Cancer (ProMisE), in order to identify biomarkers that could improve prognostic stratification within the No Specific Molecular Profile (NSMP) subgroup of endometrial cancers.This systematic review and meta-analysis was conducted according to PRISMA guidelines. We searched PubMed, Scopus and Web of Science for studies published up to December 2024. We included prospective and retrospective studies assessing the prognostic impact of molecular alterations not included in the ProMisE classification, reporting outcomes as hazard ratios (HRs). The primary outcome was progression-free survival (PFS), and the secondary outcome was overall survival (OS), analyzed in both the overall endometrial cancer population and specifically within the NSMP subgroup.A total of 19 studies met the inclusion criteria and were included in the final analysis: 17 retrospective and 2 prospective, all observational in design. L1CAM overexpression and ER loss were identified as unfavorable prognostic factors in the overall endometrial cancer population (PFS HR 3.44 [2.57, 4.59; 95 % CI] and 3.13 [2.45, 4.00; 95 % CI], respectively) and within the NSMP subgroup (PFS HR 3.34 [2.05, 5.44; 95 % CI] and 3.14 [2.00, 4.91; 95 % CI], respectively). ARID1A mutation showed a negative prognostic impact limited to NSMPs (PFS HR 2.35 [1.09, 5.06; 95 % CI]). Conversely, β-catenin/CTNNB1 and PIK3CA/PTEN mutations did not demonstrate consistent prognostic significance in either group.These findings underscore the potential of ER loss and L1CAM overexpression as prognostic markers within the NSMP subgroup, supporting more personalized adjuvant strategies. Further research is needed to clarify the prognostic role of other alterations, such as ARID1A, specifically within NSMP tumors. PROSPERO registration number: CRD420250654207.Copyright © 2025 The Authors. Published by Elsevier Inc. All rights reserved.

Paclitaxel and carboplatin (PC) is a standard initial therapy for advanced endometrial cancer. We evaluated the efficacy and tolerability of incorporating three novel agents into initial therapy.In this randomized phase II trial, patients with chemotherapy-naïve stage III/IVA (with measurable disease) and stage IVB or recurrent (with or without measurable disease) endometrial cancer were randomly assigned to treatment with PC plus bevacizumab (Arm 1), PC plus temsirolimus (Arm 2) or ixabepilone and carboplatin (IC) plus bevacizumab (Arm 3). The primary endpoint was progression-free survival (PFS). Comparable patients on the PC Arm of trial GOG209 were used as historical controls. Secondary endpoints were response rate, overall survival (OS), and safety.Overall, 349 patients were randomized. PFS duration was not significantly increased in any experimental arm compared with historical controls (p > 0.039). Treatment HRs (92% CI) for Arms 1, 2, and 3 relative to controls were 0.81 (0.63-1.02), 1.22 (0.96-1.55) and 0.87 (0.68-1.11), respectively. Response rates were similar across arms (60%, 55% and 53%, respectively). Relative to controls, OS duration (with censoring at 36 months), was significantly increased in Arm 1 (p < 0.039) but not in Arms 2 and 3; the HRs (92% CIs) were 0.71 (0.55-0.91), 0.99 (0.78-1.26), and 0.97 (0.77-1.23), respectively. No new safety signals were identified. Common mutations and rates of mismatch repair protein loss are described by histotype. Potential predictive biomarkers for temsirolimus and bevacizumab were identified.PFS was not significantly increased in any experimental arm compared to historical controls. NRG Oncology/Gynecologic Oncology Group Study GOG-86P.Copyright © 2018 Elsevier Inc. All rights reserved.

Copy number-high endometrial carcinomas were described by The Cancer Genome Atlas as high-grade endometrioid and serous cancers showing frequent copy-number alterations (CNA), low mutational burden (i.e., non-hypermutant), near-universal mutation, and unfavorable clinical outcomes. We sought to investigate and compare the clinicopathologic and molecular characteristics of non-hypermutant -altered endometrial carcinomas of four histologic types.-mutated endometrial carcinomas, defined as -mutant tumors lacking microsatellite instability or pathogenic mutations, were identified ( = 238) in a cohort of 1,239 endometrial carcinomas subjected to clinical massively parallel sequencing of 410-468 cancer-related genes. Somatic mutations and CNAs ( = 238), and clinicopathologic features were determined ( = 185, initial treatment planning at our institution).-mutated endometrial carcinomas encompassed uterine serous ( = 102, 55.1%), high-grade endometrial carcinoma with ambiguous features/not otherwise specified (EC-NOS; = 44, 23.8%), endometrioid carcinomas of all tumor grades ( = 28, 15.1%), and clear cell carcinomas ( = 11, 5.9%). mutations were significantly more frequent in endometrioid carcinomas, mutations in clear cell carcinomas, and amplification in serous carcinomas/EC-NOS; however, none of these genomic alterations were exclusive to any given histologic type. amplification was present at similar frequencies across -mutated histologic types (7.7%-18.6%). Although overall survival was similar across histologic types, serous carcinomas presented more frequently at stage IV, had more persistent and/or recurrent disease, and reduced disease-free survival.-mutated endometrial carcinomas display clinical and molecular similarities across histologic subtypes. Our data provide evidence to suggest performance of assessment in all -mutated endometrial carcinomas. Given the distinct clinical features of serous carcinomas, histologic classification continues to be relevant.©2021 American Association for Cancer Research.

The molecular classification of endometrial cancer (EC) has proven to have prognostic value and is predictive of response to adjuvant chemotherapy. Here, we investigate its predictive value for response to external beam radiotherapy (EBRT) and vaginal brachytherapy (VBT) in early-stage endometrioid EC (EEC).

HER2 status is not routinely evaluated in endometrioid endometrial cancer (E-EMCA), though it is frequently overexpressed or amplified in high grade E-EMCA and uterine serous carcinoma. Defining characteristics and survival outcomes of HER2+ E-EMCA could reveal subsets of patients who may benefit from targeted therapies.2927 E-EMCA tumors from the Caris Life Sciences database were analyzed by next-generation sequencing and whole exome sequencing, whole transcriptome sequencing, and immunohistochemistry for molecular and genomic features in a CLIA/CAP-certified laboratory (Caris Life Sciences, Phoenix, AZ). HER2 status was determined by transcriptomic cutoff extrapolated from uterine serous carcinoma. The relationship between HER2 status and patient outcomes was determined by Kaplan-Meier analysis.HER2 positivity was detected in 5.47% of E-EMCA. Differences in molecular alterations based on HER2 status were most apparent in microsatellite stable (MSS) tumors, which displayed increased TP53 mutations and loss of heterozygosity (LOH) and decreased PTEN and CTNNB1 mutations. HER2+ tumors had increased immune checkpoint gene expression and immune cell infiltration, particularly among MSS tumors. All HER2+ tumors displayed increased MAPK pathway activation scores (MPAS) and patients with HER2+ tumors experienced worse overall survival.HER2 positivity in E-EMCA corresponds with a unique molecular landscape, particularly in MSS tumors. HER2+ tumors are also associated with increased MAPK pathway activation and exhibit features of a more active immune microenvironment. These findings suggest a potential benefit of HER2 and MAPK targeted therapies as well as immunotherapies in this patient population.Copyright © 2023. Published by Elsevier Inc.

Adenocarcinoma of the endometrium (also known as endometrial cancer, or more broadly as uterine cancer or carcinoma of the uterine corpus) is the most common malignancy of the female genital tract in the United States. It is estimated that 65,950 new uterine cancer cases will have occurred in 2022, with 12,550 deaths resulting from the disease. Endometrial carcinoma includes pure endometrioid cancer and carcinomas with high-risk endometrial histology (including uterine serous carcinoma, clear cell carcinoma, carcinosarcoma [also known as malignant mixed Müllerian tumor], and undifferentiated/dedifferentiated carcinoma). Stromal or mesenchymal sarcomas are uncommon subtypes accounting for approximately 3% of all uterine cancers. This selection from the NCCN Guidelines for Uterine Neoplasms focuses on the diagnosis, staging, and management of pure endometrioid carcinoma. The complete version of the NCCN Guidelines for Uterine Neoplasms is available online at NCCN.org.