Cleaved caspase-3 expression is a potential prognostic factor for endometrial cancer with positive peritoneal cytology.

ABSTRACT

INTRODUCTION: Positive peritoneal cytology (PPC) in endometrial cancer remains a controversial topic. Cleaved caspase-3 (CC3) and Ki-67 are excellent markers of apoptotic and proliferating cells, respectively. The objective of this study was to determine the significance of CC3 and Ki-67 expression in peritoneal cytology samples as prognostic factors for endometrial cancer with PPC. METHODS: Sixty endometrial cancer specimens with PPC alone were divided into 51 endometrioid tumours (43 endometrioid carcinomas and eight carcinomas with squamous differentiation) and nine non-endometrioid tumours (two serous carcinomas, three clear cell carcinomas and four carcinosarcomas). CC3 and Ki-67 expression in peritoneal cytology samples were immunocytochemically assessed and correlated with disease-free survival (DFS) and overall survival (OS). RESULTS: Expression levels of CC3 and Ki-67 were not associated with any clinicopathological parameter. Patients with non-endometrioid tumours had significantly shorter DFS (P = .001) and OS (P = .001). Low CC3 expression (CC3Low ) was significantly associated with shorter OS (P = .02), but not DFS (P = .13). Multivariate analysis showed that non-endometrioid histology and CC3Low were independent prognostic factors. However, Ki-67 expression was not associated with survival. When endometrioid and non-endometrioid tumours were assessed separately, CC3Low was significantly associated with shorter DFS (P = .002) and OS (P = .002) in patients with non-endometrioid tumours. CONCLUSIONS: Our results suggest that CC3Low in peritoneal cytology samples is a poor prognostic factor in patients with endometrial cancers, especially non-endometrioid tumours. Immunocytochemical analysis of CC3 expression could potentially facilitate identification of patients with high-risk endometrial cancer with PPC.