A Giant Epidermal Cyst in the Gluteal Region: A Case Report.

Epidermal cysts are the most commonly occurring cysts in the subcutaneous plane and are usually asymptomatic, small, and slow growing. When the size of an epidermal cyst is greater than 5 cm, it is considered a giant epidermal cyst. Common etiologies include sun-damaged skin and acne vulgaris, and they can appear anywhere in the body, but preferably over the face, neck, and trunk. Unusual sites include the breast, penis, spleen, bones, subungual region, palms, soles, and buttocks. In this report, we presented the case of a 31-year-old female having a large, painless, gradually progressing swelling for two years in the left gluteal region, which was insidious in onset and slow-growing. The patient eventually described a discomfort that made it impossible for her to sit for long hours or sleep in a supine position. Clinical examination revealed circumscribed mass over the left gluteal region from which diagnosis of giant lipoma was confirmed, but due to its large size and involvement of the whole left buttock, we considered it important to perform an ultrasound examination to reinforce our diagnosis, which revealed a large cystic mass in the left gluteal subcutaneous plane that was excised. As a definitive management, surgery was performed with excision of the swelling, which was extracted in toto and was identified as a cyst, and on histopathological examination, the cyst wall was lined by stratified squamous epithelium. Hence, this case report highlights a rare case of a giant epidermal cyst in the gluteal region.