We aimed to evaluate whether hysteroscopy increases the risk of intraperitoneal dissemination or worsens the prognosis of endometrial carcinoma (EC) patients and whether radical hysterectomy (RH) improves overall survival (OS) or disease-free survival (DFS) in patients with stage II to III EC and to investigate the effects of different procedures for identifying EC and the effects of different surgical methods on the OS and DFS of endometrial cancer patients.Four hundred sixty-five women with EC were included in this retrospective study. Log-rank tests and Kaplan-Meier analysis were used for the outcome comparisons of the effects of the EC diagnostic method and different hysterectomy procedures. A Cox proportional hazards model was used for univariate regression analysis.Among the three procedures for diagnosing EC (diagnostic curettage, hysteroscopy, and hysterectomy), the incidences of fallopian tube and ovarian invasion were not significantly different (p = 0.506 and 0.066, respectively). The diagnostic methods for EC had no significant effect on OS (p = 0.577) or DFS (p = 0.294). In addition, type II RH and type III RH did not improve the prognosis of patients with FIGO stage II and III disease (log-rank p = 0.914 and 0.810 for OS; log-rank p = 0.707 and 0.771 for DFS, respectively).Based on the current study evidence, the use of diagnostic hysteroscopy procedures is safe and does not increase the risk of fallopian tube and ovarian invasion of intraperitoneal dissemination or worsen the prognosis of EC patients. Type II and type III RH did not demonstrate a benefit for stage II-III EC patients.© 2023 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.