Rethinking on the management strategy of malignant phyllodes tumor of the breast: An analysis based on the SEER...

Malignant phyllodes tumor of the breast (MPTB) is a rare breast neoplasm that has a high recurrence rate and its optimal treatment strategies remain controversial. Our study used the most up-to-date database to determine prognostic factors that predict cancer-specific survival (CSS) and to evaluate the effects of different treatment strategies for MPTB. We performed a retrospective cohort study using the National Cancer Institute's Surveillance, Epidemiology, and End Results database. Women who were diagnosed with MPTB from 2000 to 2019 were included. Kaplan-Meier method and Cox proportional hazards regressions were used to evaluate the prognostic power of variables on CSS. A total of 1902 women with MPTB were included in the study, with a median follow-up duration of 87.5 months. Age was found not to independently predict CSS in patients with tumors larger than 10 cm (P = .235). Mastectomy was performed on a total of 898 (47.2%) patients including 210 women (23.4%) undergoing radiotherapy after surgery. Mastectomy showed worse CSS when compared with breast-conserving surgery in patients with tumors smaller than 10 cm. Patients undergoing radiotherapy were not inferior to non-radiotherapy patients on CSS when patients were stratified by tumor size. Breast-conserving surgery showed survival benefits for patients with small tumors (T1 and T2). Patients with radiotherapy were not inferior to non-radiotherapy patients on CSS. Treatment of patients with MPTB should be carefully selected based on different tumor sizes.