Malignant phyllodes tumor with axillary metastases: a case report

Background: Phyllodes tumors are rare fibroepithelial tumors that are sometimes malignant. Malignant phyllodes tumors typically spread hematogenously and axillary metastases are especially rare. Axillary staging and axillary surgery is not recommended for most phyllodes patients; however, there is increased risk for lymph node involvement with necrotic malignant phyllodes tumors with suspicious clinical axillary presentations. There is limited data to guide adjuvant management of malignant phyllodes tumors with and without axillary metastases. Case Description: We present a case report of a young patient who presented with a large locally advanced cystic, necrotic, and ulcerating breast tumor of unknown type. Presurgical biopsy and workup were unable to determine specific breast tumor type. A suspicious lymph node was biopsied as benign preoperatively. There was no evidence of distant metastatic disease. A wide mastectomy and sentinel lymph node biopsy were performed. Intraoperative frozen section of the sentinel lymph node revealed axillary metastatic disease. Intraoperative axillary clearance was performed. Final surgical pathology revealed a malignant phyllodes tumor with axillary metastasis. After multidisciplinary discussion, both adjuvant chemotherapy and radiation were offered. Adjuvant chemotherapy was completed. Radiation was not done. At 2.5 years of follow-up the patient has no evidence of disease. Conclusions: Axillary lymph node metastasis from phyllodes tumor is extremely rare and there is limited data to guide management of these patients. Treatment is typically individualized. The use of adjuvant chemotherapy and radiotherapy is controversial, and applied on a case-by-case basis. More case outcome data is helpful to guide decision-making for future adjuvant management. Phyllodes tumors should be considered in the differential diagnosis of enlarging breast masses even without a phyllodes diagnosis on core biopsy. The potential for axillary metastasis should be considered in necrotic malignant phyllodes tumors and those with suspicious lymph nodes on presentation.