Abstract

Phyllodes tumor (PT) is a rare type of biphasic fibroepithelial neoplasm that accounts for <1% of all breast tumours and represents 2-3% of fibroepithelial neoplasms. Malignant transformation of PT usually occurs in the stromal component, and is rare in the epithelial component. DCIS, LCIS or invasive tumors might be due to epithelial component. We report a case of ductal carcinoma in situ (DCIS) occurring with in a benign PT. A 38-year-old multipar woman applied to an other medical center with compliants of a firm, palpable, irregularly-shaped lump with an ill-defined margin in the outer upper quadrant of the left breast. An ultrasound-guided core biopsy of this lump was done on an outpatient basis and the biopsy findings were benign PT with a DCIS component. The patients has undervent segmental mastectomy. The patology results were benign phyllodes tumor with Ductal Carcinoma In situ (DCIS). DCIS was also observed in a wide area of epithelial component (70% of epithelial component). The surgical margin were 1 mm away from the tumor. The patients had re-excision operation, however the surgical margin was still closed the margin so the patient had subcutaneous mastectomy with implant reconstruction. Large sized phyllodes tumors, malign phyllodes or epithelial tumors within phyllodes tumor can be resected with negative surgical margin with oncoplastic surgery techniques. Thus, it is possible to obtain successful results both in oncologic and cosmetically in phyllodes tumors.