Solitary forearm steatocystoma simplex.

Steatocystoma simplex represents a rare, benign adnexal neoplasm derived from the pilosebaceous unit. Forearm acral involvement is uncommon and can be confused with epidermal cyst. A 40-year-old male presented with a 3 × 2 cm, firm, immobile, and asymptomatic forearm mass. Ultrasonography identified a circumscribed cystic structure containing echogenic debris without hypervascularity. Excisional biopsy established steatocystoma simplex that was lined by thin stratified squamous epithelium with an eosinophilic cuticle and attached sebaceous lobules. Resection of the lesion without injury to the capsule performed and long term follow up revealed no recurrence. The atypical dimensions and anatomical site necessitate histopathological differentiation from more common cystic pathologies. Comprehensive surgical resection remains superior to conservative modalities. This rare lesion requires the histological diagnostic confirmation and complete excision ensures long-term cure. Our case presents need to include steatocystoma in differential diagnosis of forearm cystic lesions.