Definitive Management of Malignant Phyllodes of the Breast.

BackgroundMalignant phyllodes tumors (MPT) are rare, aggressive fibroepithelial breast neoplasms with limited consensus on optimal management. While wide local excision (WLE) with ≥1 cm margins is standard, recurrence remains common, and the role of adjuvant therapy remains unclear.MethodsWe conducted a 28-year retrospective review of 14 histologically confirmed MPTs in 11 patients at a single urban safety-net hospital. Clinical, pathologic, and treatment data were analyzed to assess recurrence, metastasis, and treatment outcomes.ResultsThe median tumor size was 7.6 cm. Most patients (73%) presented with stage II disease. Surgical management included WLE alone (45.5%), WLE with radiation (27.3%), mastectomy alone (9.1%), and mastectomy with adjuvant radiation (18.2%). Local recurrence occurred in 3 patients (27.3%), all of whom were initially treated with surgery alone. Those who recurred received adjuvant radiation; no recurrences occurred after adjuvant radiation. One patient developed metastases and received systemic chemotherapy. Only 1 patient underwent genetic testing, which revealed a TP53 mutation.ConclusionsRecurrence occurred often despite margin-negative resections, highlighting the limitations of current surgical guidelines and the potential importance of tumor biology. These findings support a more individualized treatment approach that incorporates histologic features and, when appropriate, genetic testing. Adjuvant radiation may reduce the risk of recurrence in high-risk cases, although our small cohort precludes definitive conclusions. These findings should be considered hypothesis-generating and highlight the need for prospective or registry-based studies.