Clinicopathological Significance of Defective DNA Mismatch Repair in Endometrial Carcinoma: A Single-Center Study From Bahrain.

INTRODUCTION:  Endometrial carcinoma, the most prevalent gynecologic malignancy in developed countries, represents a significant public health issue worldwide. DNA mismatch repair (dMMR) deficiency is an important molecular mechanism in endometrial carcinoma development, clinical course, and prognosis. AIMS AND OBJECTIVES:  This study aimed to determine the incidence and histological subtypes of endometrial carcinoma among Bahraini women, evaluate the prevalence of MMR deficiency using immunohistochemistry in these patients and analyze the association between MMR deficiency and clinicopathological features, including potential links to Lynch syndrome. PATIENTS AND METHODS:  This single-center retrospective study included 115 endometrial carcinoma patients diagnosed between January 2020 to June 2023. Immunohistochemistry was used to assess the expression of the four main MMR proteins (MLH1, MSH2, MSH6, PMS2). Clinicopathological features and survival outcomes were compared between MMR-deficient and MMR-proficient tumors. Medical records of patients were retrieved from I-SEHA system. Statistical analysis was done using SPSS. RESULTS:  The study included a wide age range of patients, with a mean age of 59.5 years. The majority were Bahraini nationals. Endometrioid carcinoma was the most common histologic subtype (73%), followed by serous carcinoma (8.7%). Most patients presented with early-stage disease (76.8% stage I), and 39.8% had low-grade tumors. Significant proportions of cases showed loss of expression of mismatch repair (MMR) proteins MLH1 (24.2%), PMS2 (25%), MSH6 (14.5%), and MSH2 (12.7%), without significant associations with age.  Conclusion: This study found endometrial cancer to be a significant health concern in Bahrain, with a relatively high prevalence and younger age of onset compared to global averages. The data shows a predominance of endometrioid subtype and higher-grade tumors. Notably, a substantial proportion exhibited MMR deficiency, an important biomarker. These findings suggest the need for enhanced screening, early detection, and tailored treatment approaches in Bahrain. Further research and robust national cancer registries are warranted to fully understand the underlying risk factors and guide evidence-based interventions to mitigate the burden of this disease.

Update on the oncologic and obstetric outcomes of medroxyprogesterone acetate treatment for atypical endometrial hyperplasia and endometrial cancer.

AIMS: To evaluate the safety and effectiveness of high-dose oral medroxyprogesterone acetate (MPA) therapy as a fertility-sparing treatment for patients diagnosed with atypical endometrial hyperplasia (AEH) and endometrioid carcinoma G1 without myometrial invasion (G1EC). Particular attention was given to the extended administration and readministration of MPA for patients with persistent disease following initial treatment and those with recurrence. METHODS: We conducted a retrospective analysis of data from 79 patients who underwent daily oral MPA treatment between 2005 and 2024 at Nagoya University Hospital. Patient characteristics, treatment outcomes, factors contributing to recurrence, and post-MPA therapy pregnancies were examined. RESULTS: MPA therapy achieved a remarkable complete response (CR) rate of 91.1%. The median time to achieve CR was 26.0 and 40.0 weeks for AEH and G1EC patients, respectively. Importantly, 27 patients (39.7%) attained CR after more than 6 months of treatment, including 8 patients (11.8%) who achieved CR after more than a year of treatment. The recurrence rates were 52.9% for AEH and 64.7% for G1EC. Twenty eight patients resumed MPA treatment, and 23 achieved second CR. Notably, recurrence was not associated with clinical factors such as age, body mass index, or post-CR pregnancy. Among patients who attempted pregnancy after achieving CR, 22 live births were successfully achieved. CONCLUSIONS: High-dose oral MPA therapy demonstrated both safety and efficacy for preserving fertility in patients with AEH and G1EC, resulting in a high CR rate. MPA extension and readministration proved to be beneficial strategies for managing patients with recurrence and persistent disease following initial treatment.

Mesothelin promotes the migration of endometrioid carcinoma and is associated with the MELF pattern.

Mesothelin (MSLN) is expressed in the mesothelium in normal tissues but is overexpressed in various malignant tumors. In this study, we searched for genes that were more frequently expressed in cases of endometrioid carcinoma (EC) with the MELF (microcystic, elongated, and fragmented) pattern using laser microdissection and RNA sequencing, and found that MSLN was predominantly expressed in cases with the MELF pattern. The role of MSLN in EC was analyzed by generating MSLN-knockout and -knockdown EC cell lines. MSLN promoted migration and epithelial-mesenchymal transition (EMT). Moreover, we found that cadherin-6 (CDH6) expression was regulated by MSLN. MSLN is known to bind to cancer antigen 125 (CA125), and we found that CA125 can regulate CDH6 expression via MSLN. Immunohistochemical investigations showed that MSLN, CA125, and CDH6 expression levels were considerably elevated in EC with the MELF pattern. The expression of CA125 was similar to that of MSLN not only in terms of immunohistochemical staining intensity but also the blood level of CA125. Our results showed that MSLN contributes to the migration and EMT of EC cells through upstream CA125 and downstream CDH6. Therefore, MSLN has potential as a therapeutic target for EC with the MELF pattern.

Adaptive Radiotherapy for Carcinoma Endometrium With Lymphocele: A Case Report.

The case report details the adaptive radiotherapy management of a 75-year-old female diagnosed with high-grade endometrial carcinoma. The patient, who was known to be hypertensive with no other comorbidities and no family history of cancer, presented with a complaint of bleeding per vagina for six months. Following extensive investigations, she underwent a laparoscopic radical hysterectomy. Postoperative histopathology confirmed endometrial adenocarcinoma International Federation of Gynecology and Obstetrics (FIGO) stage IA, grade III. The adjuvant treatment plan included adjuvant chemoradiotherapy to the postoperative tumor bed and draining lymph nodes. On planning computed tomography (CT), the patient's lymphocele responded remarkably to radiation therapy, an unusual outcome that underscores the potential efficacy of adaptive radiotherapy in complex cases.

Genetic association of lipids and lipid-lowering drug target genes with Endometrial carcinoma: a drug target Mendelian randomization study.

Background: Aberrant lipid metabolism is intricately linked to the development of endometrial cancer, and statin lipid-lowering medications are regarded as promising adjunctive therapies for future management of this malignancy. This study employed Mendelian randomization (MR) to explore the causal association between lipid traits and endometrial cancer while assessing the potential impact of drug targets on lower lipids on endometrial cancer. Method: Two-sample Mendelian randomization was employed to probe the causal association between lipid traits and endometrial carcinoma. Drug-target Mendelian randomization was also utilized to identify potential drug-target genes for managing endometrial carcinoma. In instances where lipid-mediated effects through particular drug targets were notable, the impacts of these drug targets on endometrial carcinoma risk factors were investigated to bolster the findings. Result: No causal association between genetically predicted lipid traits (LDL-C, TG, TC, and HDL-C) and EC was found in two-sample Mendelian randomization. In drug target Mendelian randomization, genetic modeling of apolipoprotein B (APOB) (OR [95%CI]=0.31, [0.16-0.60]; p=4.73e-04) and cholesteryl ester transfer protein (CETP) (OR [95%CI]=1.83, [1.38-2.43]; p=2.91e-05) genetic mimicry was associated with non-endometrioid carcinoma. Conclusion: The results of our MR study revealed no causal association between genetically predicted lipid traits (LDL-C, TG, TC, and HDL-C) and EC. Among the six lipid-lowering drug targets, we observed a significant association between lower predicted APOB levels and higher CETP levels with an increased risk of endometrioid carcinoma. These findings provide novel insights into the importance of lipid regulation in individuals with endometrial carcinoma, warranting further clinical validation and mechanistic investigations.

Exploring metastasis and recurrence patterns in low-risk grade 3 endometrial cancer: A multicenter retrospective cohort study.

OBJECTIVE: Females with low-risk endometrial cancer typically have low lymph node metastasis risk and promising prognosis without lymphadenectomy. However, the impact of grade 3 endometrial cancer on nodal involvement, recurrence, and prognosis within this specific subgroup remains unclear. Therefore, in this study, we aimed to investigate the prognosis, patterns of metastasis, and recurrence in a subgroup of females with grade 3 early-stage low-risk endometrioid endometrial cancer. METHODS: We identified patients from the endometrial cancer cohorts of seven institutional hospitals. The study included patients who underwent hysterectomy between January 2013 and December 2021 with preoperative endometrioid histological type, less than half myometrial invasion, no tumor spread outside the corpus on imaging, normal CA-125 level, and histological grade 3. The clinicopathological characteristics and survival outcomes of the patients were collected. Recurrence-free survival was estimated using the Kaplan-Meier method and compared using the log rank test. RESULTS: Overall, 36 patients were included in this analysis. Of the 33 patients who underwent lymphadenectomy, 1 (1/33, 3.0 %) had lymph node metastasis and 27 (75.0 %) received adjuvant therapy. At a median follow-up of 58 months, three females (8 %) had recurrence and all cases involved lymph nodes. The 5-year recurrence-free survival was 88.7 %. No significant difference was observed in the recurrence-free survival between females who did and did not undergo lymphadenectomy (p = 0.554). CONCLUSION: Females diagnosed with low-risk grade 3 endometrial cancer typically have favorable prognosis. However, lymph node metastasis and recurrence risks still exist, with all recorded instances of recurrence involving lymph nodes.

Corded and Hyalinized Endometrioid Endometrial Carcinoma: A Rare Case Treated With Robot-Assisted Surgery.

Endometrial carcinoma is the sixth most common cancer among women worldwide. Minimally invasive surgery (MIS) has become the preferred treatment, offering similar survival outcomes to laparotomy with lower complication rates. Corded and hyalinized endometrioid carcinoma (CHEC) is a rare and diagnostically challenging variant of endometrioid carcinoma, first described in 2005, characterized by a biphasic appearance of traditional low-grade endometrioid adenocarcinoma and corded and spindled cells embedded in a hyaline stroma. A 55-year-old nulligravid woman presented with abnormal genital bleeding for 10 days. Initial evaluations, including transvaginal ultrasonography and histological examination, confirmed adenocarcinoma. Imaging studies (magnetic resonance imaging [MRI] and computed tomography [CT]) revealed a thickened endometrium (11 mm) with no myometrial invasion, enlarged pelvic lymph nodes, or distant metastasis. Tumor markers were within normal ranges. She underwent robot-assisted laparoscopic total hysterectomy, bilateral adnexectomy, and pelvic lymph node biopsy using the da Vinci Xi system (Intuitive Surgical, Sunnyvale, CA). Histopathological examination revealed CHEC, with characteristic epithelioid and spindled cells arranged in cords within a hyalinized stroma. Immunohistochemical staining showed focal positivity for cytokeratin AE1/AE3, weak estrogen receptor positivity, and nuclear ß-catenin expression, distinguishing it from carcinosarcoma. The diagnosis was confirmed as CHEC, FIGO 2008 stage IA (pT1aN0M0). The patient remained disease-free 18 months post-surgery. CHEC is a rare variant of endometrioid carcinoma with unique histological features. It typically presents in younger patients at an early stage and has a favorable prognosis. Accurate diagnosis is crucial to differentiate it from more aggressive tumors like carcinosarcoma, preventing overtreatment. The immunohistochemical profile, particularly nuclear ß-catenin accumulation, is useful in distinguishing CHEC from carcinosarcoma. This is the first documented case of CHEC successfully treated with robot-assisted surgery. Increased awareness among pathologists and clinicians is essential for accurate diagnosis and optimal management of this rare tumor variant.

Niraparib Maintenance Therapy for Brain Metastasis in Ovarian Endometrioid Adenocarcinoma With Peritoneal Carcinomatosis: A Comprehensive Case Study and Literature Review.

Brain metastasis is a rare complication of ovarian cancer, always found at the advanced stage. Even though different multimodal approaches are available, including surgical intervention and radiotherapy, there are no official guidelines for handling this serious complication. Poly(adenosine diphosphate-ribose) polymerase (PARP) inhibitors are a group of medications initially used for maintenance therapy in platinum-sensitive recurrent ovarian cancer. Niraparib has shown some efficacy in patients with brain metastasis due to its unique properties of penetrating the blood-brain barrier. Here, we present the case of a 51-year-old patient with advanced ovarian cancer with no germline breast cancer susceptibility gene (BRCA) mutations. Despite undergoing surgery and multiple rounds of chemotherapy, the patient's condition worsened, culminating in brain metastasis. Given her neurological issues, radiotherapy was not an option, prompting the initiation of a 300 mg dose of niraparib. To date, only sporadic case reports in the literature have described patients with ovarian cancer treated with niraparib and complicated by brain metastasis. Our case is unique because it is the first case of a patient with the endometrioid type of ovarian cancer.

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.

Endometrioid carcinoma of the fallopian tube misdiagnosed as an infected endometrioma: A case report.

INTRODUCTION: Fallopian tube cancer is a rare tumor, representing between 0.3 and 1.8 % of all malignant tumors in the gynecological sphere. Due to the proximity of the uterus and ovary, the diagnosis of primary fallopian tube cancer is very difficult to establish and relies on very strict criteria. The endometrioid form is exceptional and of controversial etiopathogenesis. Only a few cases have been previously reported. Diagnosis most often occurs incidentally during histological examination. This case presents a distinctive aspect with the rare occurrence of endometrioid-type fallopian tube cancer, notably associated with endometriosis, and initially misdiagnosed as an infected endometrioma. It underscores the diagnostic complexities encountered in identifying primary fallopian tube cancer. CASE REPORT: We present the case of a 49-year-old patient, followed for chronic pelvic pain associated with menorrhagia. Imaging revealed a myomatous and adenomyotic uterus, a right ovarian endometrioma, and a left multicystic ovarian formation with thick walls, measuring 135 mm, requiring histological verification. She underwent an exploratory laparotomy. During the procedure, extensive retro- and supravaginal adhesive tissue involving the uterus, both adnexa, and the digestive tract was found. Careful adhesiolysis was performed. The left adnexa harbored a formation suggestive of an infected endometrioma. A total hysterectomy with bilateral adnexectomy and peritoneal washing was performed. The postoperative course was uneventful. Histopathological examination revealed an endometrioid carcinoma of the left fallopian tube, classified as pT1a according to FIGO guidelines. DISCUSSION: Tubal cancer is a rare cancer of unknown etiology, underestimated, and sometimes confused with ovarian pathology. Preoperative diagnosis is difficult because the clinical presentation is polymorphic and imaging is nonspecific. The endometrioid form is exceptional and of controversial etiopathogenesis. Treatment mirrors that of malignant epithelial ovarian tumors, with prognosis depending on FIGO stage and histological type. CONCLUSION: Due to its unpredictable nature, fallopian tube cancer should not be overlooked as a differential diagnosis for any adnexal mass.

Ovarian Metastasis from Human Papillomavirus-associated Usual-type Endocervical Adenocarcinoma: Clinicopathological Characteristics for Distinguishing from Primary Ovarian Mucinous or Endometrioid Tumor.

BACKGROUND/AIM: Distinguishing ovarian metastasis of usual-type endocervical adenocarcinoma (UEA) from primary ovarian tumors is often challenging because of several overlapping features. This study aimed to investigate the clinicopathological characteristics and outcomes of patients with metastatic ovarian UEA. PATIENTS AND METHODS: Clinicopathological information was collected from eight patients with metastatic ovarian UEA. Immunostaining was also performed. RESULTS: Most patients presented with adnexal masses that were suspected to be primary ovarian tumors. All examined cases showed block p16 positivity in paired primary and metastatic tumors. Five patients who completed post-operative chemotherapy or concurrent chemoradiotherapy (CCRT) did not experience recurrence. In contrast, one patient who refused further treatment after the first CCRT cycle experienced ovarian and peritoneal metastases. One patient with isolated ovarian metastasis left untreated and developed peritoneal metastasis during follow-up. CONCLUSION: Patients with UEA who received proper management for ovarian metastases showed favorable outcomes. Given that ovarian metastatic UEA can mimic primary ovarian borderline tumor or carcinoma of the mucinous or endometrioid type, pathologists should be aware of this unusual but distinctive morphology to avoid misdiagnosis and inappropriate treatment.

Endometrial endometrioid adenocarcinoma with a malignant squamous component: is the unusual metastatic pattern unique of these tumors?

The FIGO scheme is currently applied for tumor grading of endometrioid adenocarcinoma. The current report presents a series of ten cases of endometrioid carcinomas that when applying the FIGO grading does not fully convey the true biological nature of the disease. The squamous component of these tumors is malignant; it constitutes the predominant invasive component, and it often metastasizes to unconventional sites. Half of the cohort developed distant disease recurrence within 2 years, even those with early-stage disease. Somatic mutations were analyzed, targeting 101 genes in all ten cases, and mutations in PTEN, MMR, PIK3CA, ATM, RB1, and TP53 genes were detected, often multiple mutations in the same case. None of the cases revealed unique molecular signatures or previously unreported gene mutations. Immunohistochemical staining for beta-catenin showed aberrant nuclear staining in eight of ten cases and remaining two showed cytoplasmic and membranous staining. Aggressive behavior and unusual sites of metastases are observed in this series even in low-grade tumor. The FIGO grading on smaller samples may be deceptive for these cases. Even if FIGO is applied, the pathology report should emphasize the malignant squamous component and its potential significance so that the gynecologic oncology team can formulate appropriate adjuvant treatment upfront. This case series argues that this histology should be regarded as a high-grade endometrioid carcinoma and can show unusual metastatic patterns. Further research is needed with more cases within this histologic subtype to guide recommendations on adjuvant therapies for this aggressive tumor type.

Promoter methylation status of RASSF1A and RASSF2A tumor suppressor genes in endometrial endometrioid carcinomas.

We aimed to investigate the promoter methylation status of RASSF1A and RASSF2A tumor suppressor genes in endometrial endometrioid carcinomas with p53 wild type and mismatch repair proficient. Genomic DNAs were isolated from 50 specimens (15 formalin-fixed paraffin embedded tumor tissues, 15 paired blood samples and 20 normal endometrial tissues). Bisulfide modification and methylation-specific polymerase chain reaction were performed. As a result of the study, while no significance was found for RASSF1A gene (p = 0.08), a statistically significance was found for RASSF2A gene (p < 0.001), RASSF2A gene methylation status was also found higher in high grade tumors, advanced age (≥50) and nonsmokers groups. Our results indicate that RASSF2A gene may play a role in the carcinogenesis of endometrioid and it could be potential biomarker for early detection for endometrioid carcinoma. Further and larger investigations are needed to confirm our results.

Endometroid type endometrial cancer after surgery: unravelling the interplay of sleep, fatigue, and psychological well-being.

BACKGROUND: Endometrioid carcinoma, originating in the endometrium glandular cells, is often detected early and treated by surgery. However, post-treatment life quality remains poorly studied, explicitly focusing on sleep quality, fatigue, and depression. METHODS: In this cross-sectional, observational study, 147 female patients with endometrioid-type endometrial carcinoma were evaluated using standardised tools-Pittsburgh Sleep Quality Index (PSQI), Fatigue Assessment Scale (FAS), and Beck Depression Inventory (BDI). Patients were categorised based on sleep quality and depression levels. The study employed correlation and regression analyses to examine the relationships among these variables. RESULTS: No correlations were found between sociodemographic or lifestyle variables and sleep quality, fatigue, or depression (P > 0.05). A strong correlation was identified between PSQI and FAS (r = 0.623; P < 0.001), PSQI and BDI (r = 0.291; P < 0.001), and FAS and BDI (r = 0.413; P < 0.001). Fatigue and tumour grade were potential predictors of poor sleep. Sleep quality and depression predicted fatigue, while only fatigue was a predictor for depression. Radiotherapy and external radiation rates were notably higher in the mild depression group. CONCLUSIONS: Our study suggests an imperative for integrated multi-disciplinary approaches that focus on medical and psychological aspects of patient care to enhance long-term well-being and quality of life.

Molecular classification of metastatic and recurrent endometrial endometrioid carcinoma: prognostic relevance among low- and high-stage tumours.

AIMS: Molecular classification according to The Cancer Genome Atlas (TCGA) improves endometrial endometrioid carcinoma (EEC) prognostication and has specific treatment implications; however, original data were skewed towards low-grade and low-stage tumours. Herein, we molecularly classify EECs metastatic at the time of diagnosis or with subsequently documented recurrent/metastatic disease to examine correlation with clinical outcomes. METHODS: TCGA categories include POLE-mutated, microsatellite instability (MSI), p53 abnormal (p53 abnl) and no specific molecular profile (NSMP). POLE targeted sequencing at exons 9, 11, 13 and 14 and immunohistochemistry (IHC) for PMS2, MSH6 and p53 were performed to establish molecular classification. RESULTS: The distribution in our cohort of 141 EECs was similar to that generally reported in EEC, with nine POLE-mutated (6%), 45 MSI (32%), 16 p53 abnl (11%) and 71 NSMP (50%), with similar distributions between low- and high-stage cohorts. We demonstrate that when stratified by molecular subtype, disease-specific survival from the time of high-stage (stages III-IV) presentation or time of recurrence in low-stage (stages I-II) disease among metastatic and/or recurrent EEC is strongly associated with TCGA classification (high-stage P = 0.02, low-stage P = 0.017). Discordant molecular classification between primary and metastatic/recurrent tumours occurred in four of 105 (3.8%) patients, two related to PMS2/MSH6 IHC and two related to p53 IHC. CONCLUSIONS: We demonstrate that molecular classification is prognostically relevant not only at the time of diagnosis, but also at the time of recurrence and in the metastatic setting. Rare subclonal alterations occur and suggest a role for confirming TCGA classification in recurrent/metastatic tumours.

Genetic and epigenetic alterations in precursor lesions of endometrial endometrioid carcinoma.

The hyperplasia-carcinoma sequence is a stepwise tumourigenic programme towards endometrial cancer in which normal endometrial epithelium becomes neoplastic through non-atypical endometrial hyperplasia (NAEH) and atypical endometrial hyperplasia (AEH), under the influence of unopposed oestrogen. NAEH and AEH are known to exhibit polyclonal and monoclonal cell growth, respectively; yet, aside from focal PTEN protein loss, the genetic and epigenetic alterations that occur during the cellular transition remain largely unknown. We sought to explore the potential molecular mechanisms that promote the NAEH-AEH transition and identify molecular markers that could help to differentiate between these two states. We conducted target-panel sequencing on the coding exons of 596 genes, including 96 endometrial cancer driver genes, and DNA methylome microarrays for 48 NAEH and 44 AEH lesions that were separately collected via macro- or micro-dissection from the endometrial tissues of 30 cases. Sequencing analyses revealed acquisition of the PTEN mutation and the clonal expansion of tumour cells in AEH samples. Further, across the transition, alterations to the DNA methylome were characterised by hypermethylation of promoter/enhancer regions and CpG islands, as well as hypo- and hyper-methylation of DNA-binding regions for transcription factors relevant to endometrial cell differentiation and/or tumourigenesis, including FOXA2, SOX17, and HAND2. The identified DNA methylation signature distinguishing NAEH and AEH lesions was reproducible in a validation cohort with modest discriminative capability. These findings not only support the concept that the transition from NAEH to AEH is an essential step within neoplastic cell transformation of endometrial epithelium but also provide deep insight into the molecular mechanism of the tumourigenic programme. © 2024 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Staining Pattern of Alcian Blue in Endometrial Cytology: Utility in Distinguishing Grade 1-Endometrial Endometrioid Carcinoma from Endometrial Glandular Stromal Breakdown.

Background and Objective: In endometrial cytology, differentiating endometrial glandular stromal breakdown (EGBD) from endometrial endometrioid carcinoma (G1-EEC) is often difficult. In this study, we provided a new focus on chondroitin sulfate (CS), a major substrate component of the endometrial stroma, and assessed the diagnostic utility of Alcian Blue (AB) staining in the differential diagnosis in liquid-based cytological (LBC) samples. Materials and Methods: LBC specimens from 19 patients with a proliferative endometrium, 36 with EGBD, and 30 with G1-EEC who underwent endometrial cytology were stained with AB (pH 1.0), and their reactivity was observed. In addition, immunocytochemical staining of CS and CD31 was performed for five cases each to evaluate their interrelationship with blood vessels. Results: Regarding the 30 G1-EEC cases, at least one of the three representative staining patterns was observed by AB staining: dot-like, microtubular, and finely branched linear patterns. Moreover, the inner portion of the tubular material observed by AB staining expressed CD31. Conversely, in the 36 EGBD cases, only five metaplastic clusters with irregular protrusions and condensed stromal clusters (CSCs) showed a dot-like positive pattern, and background CSCs did not show reactivity to AB staining in any of the cases. Furthermore, the vascular structure expressing CD31 in cell clusters was also unclear. Conclusions: We demonstrated that AB staining shows different staining patterns in G1-EEC and EGBD, reflecting their different tissue structures. Our data provide new insights into endometrial cell diagnosis changes and demonstrate that AB staining is a potential new diagnostic aid tool for the differentiation of G1-EEC from EGBD.

Risk of endometrial cancer after RRSO in BRCA 1/2 carriers: a multicentre cohort study / Riesgo de cáncer de endometrio después de RRSO en portadoras de BRCA 1/2: un estudio de cohorte multicéntrico

Objective: To know the risk of endometrial cancer (EC) in a population of women with BRCA 1/2 pathogenic or likely pathogenic variants after risk-reducing salpingo-oophorectomy (RRSO). Methods: The study cohort included data from 857 women with BRCA mutations who underwent RRSO visited four hospitals in Catalonia, Spain, from January 1, 1999 to April 30, 2019. Standardized incidence ratio (SIR) of EC was calculated in these patients using data from a regional population-based cancer registry. Results: After RRSO, eight cases of EC were identified. Four in BRCA 1 carriers and four in BRCA2 carriers. The expected number of cases of EC was 3.67 cases, with a SIR of 2.18 and a 95% CI (0.93–3.95). Conclusions: In our cohort, the risk of EC in BRCA1/2 carriers after RRSO is not greater than expected. Hysterectomy is not routinely recommended for these patients.(AU)

TTN Mutation in Endometrial Endometrioid Carcinoma Is Associated with Poor Clinical Outcomes and High Tumor Mutation Burden.

Endometrioid endometrial carcinoma (EEC) stands as a prevalent gynecologic malignancy in developed regions. However, predicting relapse cases remains challenging, necessitating the identification of a novel biomarker for EEC relapse. The assessment of tumor mutational burden (TMB) is pivotal for immunotherapy in EEC patients. However, both whole-exome sequencing (WES) and targeted sequencing encountered application-related difficulties. In light of this, standardized and simplified techniques for TMB measurement are imperative. In this study, we employed WES on 25 EEC patients (12 relapsed cases and 13 non-relapsed cases) who accepted hysterectomy surgery (CHCAMS cohort). We additionally obtained a total of 391 tumor samples with clinicopathological features from TCGA website to broaden the study cohort. In the CHCAMS cohort, the TTN mutant group showed shorter progression-free survival (p < 0.001) and overall survival (p < 0.001) than TTN wild-type group. Additionally, we discovered that the number of TTN mutations per sample was significantly linked with TMB-WES in CHCAMS cohort and TCGA cohort (p < 0.05). And the number of TTN mutations per sample in POLE mutant group was greater than in the POLE wild-type group (p < 0.0001). In conclusion, TTN mutation may serve as a biomarker for EEC prognosis. TTN mutation is also associated with WES-TMB, and could be a simplified TMB measurement technique.

A Rare Case Report of Dedifferentiated Endometrioid Carcinoma.

Dedifferentiated endometrioid carcinoma (DEC) is an exceptionally rare subtype of endometrial cancer characterized by a high-grade component juxtaposed with a low-grade endometrioid adenocarcinoma. This case report presents a unique instance of dedifferentiated endometrioid carcinoma in a 64-year-old female patient who presented with post-menopausal bleeding and abdominal pain. Diagnostic evaluation including imaging studies and histopathological examination revealed a mixed tumor comprising both high-grade and low-grade components. Management involved a multidisciplinary approach including surgical resection followed by adjuvant chemotherapy and radiation therapy. They are frequently mislabeled as endometrioid carcinomas of International Federation of Gynecology and Obstetrics (FIGO) Grade 2 or Grade 3. It is crucial to correctly differentiate these instances from traditional endometrioid carcinomas. This case underscores the importance of early recognition and comprehensive management strategies tailored to the unique characteristics of dedifferentiated endometrioid carcinoma. We report this case due to its rarity and complexity in diagnosis.