Prognosis and treatment of uterine leiomyosarcoma: A National Cancer Database study.

Objective: To determine overall survival and factors associated with survival of women with uterine leiomyosarcoma.

Methods: We performed an observational cohort study of women with uterine leiomyosarcoma (n=7455) from the 1998-2013 National Cancer Database. Kaplan-Meier and multivariable accelerated failure time survival analyses were performed to investigate predictors of survival. Sensitivity and matched cohort analyses were performed to evaluate the roles of oophorectomy, lymphadenectomy, and chemotherapy in early leiomyosarcoma and chemotherapy in metastatic leiomyosarcoma.

Results: Median (interquartile range) age at diagnosis was 54 (48-63) years. Older age, higher comorbidity, black race, higher stage or grade, larger tumor size, lymph node involvement, metastasis at diagnosis, positive surgical margin, adjuvant chemotherapy, and brachytherapy were independently associated with decreased survival by unmatched cohort analyses. Private insurance was associated with increased survival. By matched cohort analyses, omitting oophorectomy was not associated with survival among women≤51years old at diagnosis (event time ratio (ETR) (95% CI) 1.06 (0.90-1.25), P=0.48). Omitting lymphadenectomy was not associated with survival (ETR (95% CI) 1.02 (0.94-1.10), P=0.60). Among women with stage I leiomyosarcoma, adjuvant chemotherapy was not associated with increased survival (ETR (95% CI) 0.91 (0.78-1.05), P=0.18). Chemotherapy was associated with increased survival of women with metastatic leiomyosarcoma (median survival (95% CI) 19.4 (16.4-23.0) versus 10.9 (7.7-14.3) months, ETR (95% CI) 1.66 (1.46-1.90), P<0.001).

Conclusion: Early and complete resection is the best-evidenced treatment for uterine leiomyosarcoma. Oophorectomy and lymphadenectomy may be safely omitted for clinically uterus-confined leiomyosarcoma. Chemotherapy increases survival of women with metastatic leiomyosarcoma.