Diagnostic hysteroscopy and positive peritoneal cytology in endometrial cancer: The influence of tumor molecular features

Abstract

Objective

To evaluate diagnostic hysteroscopy, mismatch repair (MMR) status, and p53 expression in relation to positive peritoneal cytology (PPC) in endometrial cancer.

Methods

We conducted a retrospective cohort study of women who underwent surgical staging for histologically confirmed endometrial carcinoma at a tertiary medical centre between January 2016 and December 2024. Only patients with available peritoneal cytology were included. Clinical, pathologic, and molecular data were extracted from electronic medical records. Associations between diagnostic modality, molecular characteristics, and PPC were evaluated using univariable and multivariable analyses.

Results

A total of 212 women were included, of whom 46 (21.7 %) had PPC. Endometrioid adenocarcinoma was the predominant histological subtype (69.8 %), and most tumors were FIGO stage I–II (76.9 %). On univariable analysis, PPC was significantly associated with non-endometrioid histology, deep myometrial invasion, lymphovascular space invasion, advanced-stage disease, and abnormal p53 expression. After adjustment for age, disease stage, histological subtype, and MMR status, advanced-stage disease remained independently associated with PPC (adjusted odds ratio [aOR] 7.46, 95 % CI 2.87–19.41). Hysteroscopy-based diagnosis was not independently associated with PPC (aOR 1.67, 95 % CI 0.67––4.20). Neither MMR deficiency nor abnormal p53 expression was independently associated with cytologic positivity.

Conclusion

Hysteroscopy-based diagnosis was not independently associated with PPC after adjustment for clinicopathological and molecular factors. Advanced-stage disease remained independently associated with PPC. These findings add a molecular perspective to the interpretation of cytologic positivity following diagnostic hysteroscopy.