Phyllodes tumors of the breast

The aim of this study was to describe the clinical, mammographic, and sonographic findings of phyllodes tumor of the breast and correlate them to the benign or malignant pathological nature of the lesion and its clinical behavior. We retrospectively reviewed the clinical, radiologic, and pathologic findings of 12 cases of phyllodes tumors diagnosed in our hospital in the past 6 years, 6 of which were malignant. The surgical management and clinical course of the patients were also reviewed. Mammographically, soft tissue masses ranging from 2.5 to 15 cm were present in all patients. One patient had a mixed fat and water density mass and 2 patients had masses associated with coarse calcifications. At sonography, all tumors were well circumscribed; two of them were homogeneously hypoechoic, and the rest had heterogeneous internal echoes. Eight patients showed internal cystic areas. None of these characteristics proved to be useful in ascertaining the benign or malignant nature of the tumor. At surgery, 5 patients underwent mastectomy and 7 patients local excision of the tumor. Three of the later tumors, one benign and two malignant, recurred after several months. Fine-needle aspiration biopsy suggested the diagnosis of phyllodes tumor in only 3 cases. After surgery, six tumors were classified as benign and six as malignant, three of which being of low-grade malignancy. None of the clinical or radiologic characteristics of the tumors were useful in predicting their histological nature or their behavior after surgery. Preoperative fine-needle aspiration biopsy often misdiagnosed the tumor as benign fibroadenoma. Only the histopathologic features of the excised mass proved to be helpful in assessing malignancy. Received: 3 July 1997; Revision received: 18 December 1997; Accepted: 28 April 1998