Granular cell tumor in a premenstrual female breast.

Granular cell tumor is an exceedingly rare pediatric breast mass, derived from Schwann cells which are most commonly observed in the oral cavity, skin, and subcutaneous tissue. When they occur in the breast, they can mimic intrinsic breast masses. Most cases are benign, but malignant cases have been reported. We present a case of a premenstrual, African-American 9 year old female with a painful right breast mass originally felt to be an epidermal inclusion cyst. An ultrasound was performed 17 months after original presentation which demonstrated a 1 cm well-circumscribed solid ovoid mass. Despite the relatively small size and benign imaging appearance of the mass, surgical resection was performed for symptom relief given the associated pain. This is the first known case of granular cell tumor of the breast in a premenstrual female.