Recurrent borderline phyllodes tumor in nipple: a rare case report and review of the literature

Phyllodes tumor (PT) of the breast is a rare tumor. They are usually located in the four quadrants of the mammary gland and may also appear below the nipple. Although there have been a number of cases reported, here we report a very rare case of this tumor in an unusual location. The patient has been diagnosed with right breast borderline PT, who accepted breast-conserving surgery. Twelve months after surgery we found right nipple enlargement, without nipple discharge, ipsilateral and contralateral breast without palpable mass. Interestingly, ultrasound showed a lesion in the right nipple: a hypoechoic mass with a diameter of 2.0 cm was seen in the nipple, with no significant calcification. The patient underwent nipple-sparing mastectomy without postoperative adjuvant radiotherapy. Histopathological and immunohistochemical analysis demonstrated a borderline PT. There were no signs of recurrence after two years of follow-up. We consider that wide surgical resection and negative margin are still the main methods for the treatment of recurrent borderline PTs.