Detailed report on the clinicopathological factors of patients with endometrial cancer in Japan: a JSOG gynecologic tumor registry-based study

In this study, we collected data over 8 years (2012-2019) from the Japan Society of Obstetrics and Gynecology (JSOG) tumor registry to determine the status of endometrial cancer in Japan, and analyzed detailed clinicopathological factors. The JSOG maintains a tumor registry that gathers information on endometrial cancer treated at the JSOG-registered institutions. Data from the patients whose endometrial cancer treatment was initiated from 2012 to 2019 were analyzed retrospectively. A total of 82,969 patients with endometrial cancer underwent treatment from 2012 to 2019. Chemotherapy alone or in combination with hormonal therapy is more common among endometrial cancer patients under 40 years compared with those over 40 years. The number of patients with endometrial cancer, treated with laparoscopic or robot-assisted surgery was observed to have increased yearly. Small cell carcinomas and undifferentiated carcinomas were more likely to be diagnosed at an advanced stage. Lymphadenectomy was most commonly performed for stage IIIC2 disease, whereas positive peritoneal washing cytology was most common for stage IVB and serous carcinoma. Multi-year summary reports provided detailed clinicopathological information regarding endometrial cancer that could not be obtained in a single year. These reports were useful in understanding treatment strategies and trends over time based on age, histology, and stage.