[摘要]:This study was conducted to evaluate the significance of circulating free DNA (CFDNA), p53 antibody (p53-Ab) and mutations of KRAS gene in the development of endometrial cancer (EC). A total of 109 patients with EC (87 patients with Type I and 22 patients with Type II) took part in this study. KRAS mutations and CFDNA were detected by means of the PCR-RFLP and enriched by the PCR-RFPL method. ELISA was used to analyze plasma p53-Ab. Tissue expression of P53 protein was evaluated immunohistochemically (IHC). The frequency of KRAS mutations was especially high in Grade 2 of Type I EC. CFDNA was frequently detected in patients with early stage of Type II EC at a low level of grade. It is noteworthy that the p53-Ab positive rate increased in the higher grade of Type I tumors. A significant difference in the number of cases with the p53-Ab was found in the advanced stage of Type I tumors. The frequency of KRAS and p53-Ab correlates with tumor stage only in the Type I EC. Plasma CFDNA and p53-Ab offer a chance to develop a procedure for EC Type II diagnosis. The association between tumor cells related to CFDNA and p53-Ab with Type II tumor suggests that it might potentially serve as a marker in predicting the prognosis and offers a possibility to individualize treatment regimen.