A Case of Resectable Malignant Phyllodes Tumor of the Breast with Pancreatic Metastasis

Abstract

A 49-year-old woman visited our hospital complaining of a mass in the right breast. She was followed-up because needle biopsy revealed no malignant findings. The tumor had rapidly grown eight years after her initial visit, and the pathological diagnosis was malignant phyllodes tumor of the breast. Additional surgical resection was performed, but the margins were positive. The patient refused further resection. Therefore, imaging studies were performed every 3 months. Two years after the additional surgical resection, abdominal CT revealed a mass lesion in the pancreatic body and tail, and pancreatic metastasis from a malignant phyllodes tumor was diagnosed using EUS-FNA. Surgical resection was performed because of the lack of metastasis to other organs. We were able to perform radical resection without cancer remnants despite left adrenal infiltration and swelling of the peripancreatic lymph nodes. No recurrence had occurred at 2 years and 9 months after the operation. Malignant phyllodes tumors with distant metastases have a poor prognosis owing to their rapid progression and lack of established and effective treatments. However, a long-term prognosis can be expected if surgical resection is possible, as in our case.