A Rare Case of Benign Granular Cell Tumor of the Breast

Granular cell tumor is a rare benign non-encapsulated tumor that mostly presents in oral cavity. Breast localization is uncommon and occurs in about one per 1000 cases of breast cancers. It mainly affects premenopausal women showing the possible role of estrogen and progesterone levels in the progression of this tumor. Granular cell tumor is a great emulator of the invasive ductal carcinoma of the breast clinically and radiologically, and the definite diagnosis especially in fine needle aspiration cytology (FNAC) is a great challenge. Granular cell tumor almost always has a benign clinical behavior and malignant transformation is seen in less than 1 of cases, which requires additional therapy other than local surgical resection. Here, we report a rare case of benign granular cell tumor of breast that should be differentiated from other breast neoplasms especially invasive carcinomas. © 2020, Kerman University of Medical Sciences. All rights reserved.