Analysis of the Correlation between Ki-67 Expression in Endometrial Cancer and Clinicopathological Characteristics and Prognosis of Patients

Objective: This study aimed to explore the correlation of proliferative cell nuclear antigen -67 (Ki -67) with clinicopathological characteristics and prognosis in endometrial cancer (EC) patients. Methods: The study included 216 EC patients admitted from January 2010 to December 2014. The corresponding clinicopathological data of the patients were collected and comprehensively analyzed. Their tissue samples were collected during surgical procedures and the patients were followed up for 3 to 60 months. Receiver operating characteristic curve (ROC) was drawn to determine the critical value of Ki -67 for predicting the prognosis and occurrence of postoperative events. Spearman correlation analysis and Kaplan -Meier survival curve were used for the evaluation of patient prognosis. Results: The expression of Ki -67 >67% did not show a significant correlation with patient age, gravidity, menopause, family history, and tumor size, but exhibited a significant correlation with pathological classification, pathological type, depth of myometrial invasion, lymphatic vascular space invasion, lymph node metastasis, International Federation of Gynecology and Obstetrics (FIGO) stage, and histological grade. Furthermore, the expression of Ki -67 >67% in cancer tissue was negatively correlated with the expression of estrogen receptor (ER) and progesterone receptor (PR) (r = -0.818 and -0.842, p < 0.001). Conversely, it indicated a positive correlation with the expression of human epidermal growth factor receptor-2 (HER -2) and tumor suppressor gene (P53) (r = 0.613 and 0.587, p < 0.001). Moreover, the Kaplan -Meier survival curve analysis revealed a substantial association between the expression level of Ki -67 and the 5 -year survival rate of EC patients. Concurrently, the 5 -year event-free survival rate was significantly lower in patients with Ki -67 >67%+ER-negative and (or)+PR-negative compared to those with Ki -67 >67%+ER-positive and (or)+PR-positive (p < 0.001). Additionally, it was also lower in patients with Ki -67 >67%+HER-2-positive and (or)+P53-positive compared to those with Ki -67 >67%+HER-2-negative and (or)+P53-negative (p < 0.001). Conclusion: The elevated expression of Ki -67 exhibits a strong correlation with the poor clinicopathological characteristics of EC patients, suggesting a poor prognosis in EC patients with Ki -67 >67%.