Diagnosis, characteristics, and treatment of breast carcinomas within benign fibroepithelial tumors.

ABSTRACT

BACKGROUND: Breast carcinoma arising in a benign fibroepithelial tumor is rare, and is usually discovered incidentally during examination of the breast mass. METHODS: We evaluated the clinicopathological features, treatment, and prognosis of seven women with breast carcinomas within benign fibroepithelial tumors, diagnosed and treated at a single institution between 2011 and 2015. RESULTS: Seven women, aged 21-64 years, visited our hospital complaining of a breast mass detected by self-checking or screening examination. All patients had well-demarcated movable breast masses. Ultrasonography showed circumscribed masses suggesting benign tumors in all cases, and mammography revealed well-defined, high-density masses, with or without calcification. The masses progressed in two patients. A preoperative histological diagnosis of carcinoma was made following needle biopsy in four patients. Tumorectomy, breast-conserving surgery, and mastectomy were performed in three, two, and two patients, respectively. One patient underwent lymph node dissection and another underwent sentinel node biopsy. Histologically, the masses were diagnosed as invasive ductal carcinoma, ductal carcinoma in situ or lobular carcinoma in situ, arising in a benign phyllodes tumor, fibroadenoma, or fibroadenomatoid mastopathy. Lymph node metastasis was detected in two patients. There was no recurrence in any of the patients. CONCLUSIONS: Although a carcinoma within a preexisting benign fibroepithelial tumor is extremely rare, it is important to be aware of the possibility of invasive and metastatic disease.