There is fat in this sclerosis: A case report of sclerotic lipoma and review of the literature

Abstract

Sclerotic lipomas, a lipoma variant, are benign subcutaneous tumors, so-named because of their resemblance to sclerotic fibromas. Previous literature has suggested that these tumors may show a predilection for middle-aged adult males. We report an unusual case of a sclerotic lipoma diagnosed on the scalp of a 66-year-old female.The patient presented to the outpatient clinic with a 3-to 4-year history of an enlarging and irritated 2.6-cm nodule on the anterior crown of the scalp, clinically thought to be a pilar cyst. Histopathological examination from the excisional specimen revealed a well-circumscribed dermal to subcutaneous tumor with ample sclerotic collagen bundles, an increased number of CD34 positive spindled cells, and prominent S-100 positive mature adipocytes comprising greater than 50% of the tumor.We present this case given its atypical clinical and histopathological presentation, review the literature of sclerotic lipomas, and discuss the differential diagnosis to raise awareness of this rare entity. K E Y W O R D S lipoma variant, sclerosing fibroma, sclerotic lipoma, spindle cell lipoma