Granular cell tumor (GCT) is a rare soft tissue neoplasm of Schwann cell origin. Most cases occur in adults; however, the precise incidence is unknown in children. GCT is usually a slow-growing, painless tumor involving the skin and soft tissues that is mostly located in the head and neck region, especially the tongue. The breast is one of the least common sites involved by GCT. This paper presents a 3-year-old girl who presented with a soft to firm, ill-defined swelling on the right breast with painful ulceration of the overlying skin. Fine needle aspiration rendered an initial diagnosis of fibrocystic change accompanied by apocrine metaplasia. Histologic evaluation of the excised breast mass revealed a benign granular cell tumor. Although rare, GCT of the breast should be included in the differential diagnosis for breast masses in pediatric patients. Proper diagnosis and timely management of this tumor are essential because of its malignant potential (<2% of cases) and high rate of local recurrence if not properly excised.
Keywords: Breast; S100 Proteins; Schwann Cells.