Newly Arising Contralateral Granular Cell Tumor after Wide Excision of Large Breast Granular Cell Tumor: A Case Report

Granular cell tumor (GCT) of the breast is a rare neoplasm that is usually benign in nature. The results of physical examination and ultrasonographic findings of GCT of the breast often mimic those of other malignancies. A 46-year-old woman underwent wide excision for removal of a large mass in the left breast (about 10 cm in diameter). The pathologic finding of the excised mass was benign GCT. A year after initial surgery, recurrence of the left breast mass was found along with a newly developed mass in the contralateral right breast, which was excised. In this study, we describe the case of a newly developed GCT in the contralateral breast 1 year after excision of a larger breast GCT.