A Qualitative Systematic Review of the Significance of Adjuvant Therapy in Patients with Low-Risk Endometrial Cancer Presenting Positive Peritoneal Cytology: a Relevant Study to the Guideline Update for Endometrial Cancer by the Japan Society of Gynecologic Oncology Guideline Committee.

In association with an update of the Japan Society of Gynecologic Oncology clinical practice guidelines for endometrial cancer in 2023, a systematic review was conducted about the therapeutic benefit of adjuvant therapy on patients with early-stage endometrial carcinoma, who presented positive peritoneal cytology (PPC) without the risk factors for recurrence. The systematic review only included two eligible retrospective studies. Both studies included patients with risk factors for recurrence. A nationwide study in the United States reported that adjuvant chemotherapy was associated with the reduced risk of death among patients with stages I-II endometrial cancer with PPC by multivariate, propensity score-adjusted analysis. Another single-center study in Japan reported no association between adjuvant chemotherapy and relapse-free survival among patients with stage IA endometrial cancer by univariate analysis. This systematic review identified that evidence was limited with conflicting results. Continuous evaluation is warranted to address this clinical question. In early-stage endometrial cancer, the therapeutic benefit of adjuvant therapy on patients with positive peritoneal cytology remains controversial. This systematic review identified that evidence was limited with conflicting results.