Prognostic indicators of recurrence and treatment-free interval in uterine carcinosarcoma.

Objective: To evaluate prognostic factors influencing recurrence and treatment-free interval in patients with uterine carcinosarcoma (UCS).

Methods: A single-institution cohort study of 73 patients with UCS from 2009 to 2023 was conducted. Patients underwent surgery and adjuvant chemotherapy ± radiation. Demographic and clinicopathologic data were collected and analyzed using Kruskal-Wallis, chi-square, and Fisher's exact tests. Multivariate Cox regression and Kaplan-Meier analyses assessed predictors of recurrence and survival outcomes.

Results: A total of 118 patients with UCS were identified, 73 of whom underwent surgery followed by platinum-doublet chemotherapy ± radiation. Forty-six patients (63 %) had recurrence, with 23 (50 %), 14 (30 %), and 9 (20 %) recurring <6 months, between 6 and 12 months, and > 12 months after completing chemotherapy, respectively. Independent predictors of recurrence included stage (p = 0.013), age (p < 0.001), adjuvant radiation (p = 0.003), and tumor size (p = 0.002). Adjuvant radiation with chemotherapy was associated with significant PFS (p < 0.001) and OS (p = 0.002) benefit. Among those who recurred, primary treatment-free interval was significantly associated with overall survival. Adjuvant radiation (p = 0.002) and tumor size (p < 0.001) were also independent predictors of treatment-free interval.

Conclusion: There are clinically significant predictors of recurrence and treatment-free interval in UCS, including tumor size and the additional of adjuvant radiation. Treatment-free interval is a strong prognostic indicator of overall survival. Adjuvant radiation with chemotherapy provides a significant PFS and OS benefit.