Adjuvant chemotherapy for malignant phyllodes tumor of the breast

Malignant phyllodes tumor of the breast (MPTB) is rare and usually presents as a large rapidly progressive mass which might metastasize distantly. The survival benefit of breast surgery is unquestionable; on the other hand, adjuvant radiotherapy and chemotherapy are controversial. In this study, chemotherapy endpoints are reviewed and underlying factors related to the outcomes are discussed. We performed a systematic review based on studies reporting disease-free survival (DFS) and/or overall survival (OS) rates with chemotherapy as variable in MPTB patients. The search generated 246 studies and 3 were included. They present together 199 patients, 77 (39%) with aggressive histology and 29 (15%) received chemotherapy. One study reported better DFS and OS outcomes in treatment group whilst two reported the opposite, but neither results were statistically significant. Unbalanced arms, small sample size, absence of prognostic factors stratification and inclusion of indolent subtypes are factors that might have contributed to these results. Therefore, the negative benefit of adjuvant chemotherapy in survival of MPTB is based on few studies with considerable limitations. High risk MPTB should be properly studied in randomized prospective trials, specially taking into account prognostic and predictive molecular markers of response.