Prognostic factors and survival outcomes of immunohistochemically detection based-molecular subtypes of endometrial cancer-analysis of 576 clinical cases.

Objective: The study aimed to identify distinct molecular subtypes of endometrial cancer (EC) by immunohistochemistry and to analyze their pathological characteristics, independent prognostic factors, and patient survival outcomes for potential clinical applications.

Method: 576 patients with preoperative EC confined to the uterus were divided into three subgroups based on the immunohistochemical detection method: MMR-deficiency (MMRd), P53 wild type (P53wt) and P53 abnormal (P53abn). These subgroups were retrospectively analyzed, and their pathological characteristics, prognostic factors and survival outcomes were compared.

Results: We identified 401 (69.6%), 123 (21.4%), and 52 (9%) cases of P53wt, MMRd, and P53abn subgroups, respectively. A significant difference was observed in the median age of onset, tumor stage, high-grade tumor differentiation, non-endometrioid carcinoma, myometrial invasion, lymphovascular invasion, the incidence of lymph node metastasis postoperative, and expression of ER and PR receptors among the three groups. Pathological type, lymphovascular invasion, ER and PR expression were identified as independent prognostic factors for disease-free survival (DFS). Additionally, pathological type, lymphovascular invasion, myometrial invasion, and PR expression were recognized as independent prognostic factors for overall survival (OS) in the study cohort. However, the survival outcome for P53abn was the worst, with lymphovascular invasion identified as an independent prognostic factor for DFS. Lymph node status, FIGO stage, and ER expression were identified as independent prognostic factors for OS.

Conclusion: The study concludes that immunohistochemical detection-based subtyping of EC holds clinical practicality and can be employed to explore both pathological and clinical prognoses for EC patients.