Prognostic Factors in Uterine Sarcoma Based on the Tumor Size Stratification: A Retrospective Study

Uterine sarcoma is a rare malignant gynecological tumor with a poor prognosis. Many studies have identified the clinical stage as an important prognostic factor; however, the heterogeneity of patient distribution in the International Federation of Gynecology and Obstetrics (FIGO) stage has reportedly required further revision. Therefore, this study retrospectively investigated the factors related to the prognosis of uterine sarcoma, with particular attention to tumor size, which can be evaluated preoperatively.

Clinical data were extracted from the medical records of patients with uterine sarcoma treated between January 2010 and January 2023. Kaplan-Meier survival curves were plotted according to clinical factors such as histological type, clinical stage, chemotherapy, and tumor size. Factors that were significant in the univariate analysis were subjected to the multivariate analysis using Cox proportional hazards regression.

Thirty-four patients with uterine sarcoma, comprising 24 (70.5%), five (14.7%), three (8.8%), and two (5.9%) with leiomyosarcoma, undifferentiated sarcoma, high-grade endometrial stromal sarcoma, and low-grade endometrial stromal sarcoma, respectively, were included. Based on the FIGO stage, 15 (44.1%), six (17.6%), three (8.8%), and 10 patients had stage I, II, III, and IV disease, respectively, at the time of diagnosis. All patients underwent surgery as initial treatment; 15 received postoperative chemotherapy. Among the 32 patients with uterine leiomyosarcoma, undifferentiated sarcoma, or high-grade endometrial stromal sarcoma, overall survival differed significantly in the univariate analysis based on disease stage (I + II vs. III + IV) and tumor size (≤10 vs. >10 cm). However, only tumor size was an independent prognostic factor in the multivariate analysis.

Tumor size (≤10 vs. >10 cm) may possibly have a prognostic impact on uterine sarcoma.