Clinicopathological and immnuohistochemical findings in a series of folliculosebaceous cystic hamartoma

Abstract

Folliculo-sebaceous cystic hamartoma (FSCH) is an uncommon skin condition presenting as a slow-growing papulo-nodular lesion, in or around the nose. Most cases are not clinically suspected and only histopathological examination allows the diagnosis. Pathological features include a dermal-located infundibulo-cystic structure with sebaceous glands radiating around, a stromal component encircling the epithelial structures, with clefts between the lesional epithelial and stromal parts, as well as between this and the adjacent dermis. We report eight patients with the diagnosis of FSCH (5 females and 3 males), with ages ranging from 35 to 77 years. Most cases (5 out of 8) were located in or around the nose and sizes were comprised between 0.6 and 1.2 cm. Lesions had grown for long periods of time, up to ten years in one case. Immunohistochemistry showed staining for p63 in the epithelial component of all lesions, while CD10 was only present in some sebocytes. CD34 and Factor XIIIa positive cells were present in the lesional stroma. Staining for androgen and alpha-estrogen receptors was also usually noticed. FCSH is a hamartomatous skin lesion, clinically indistinct but with well-defined histopathological features. Immunohistochemistry shows a profile very close to normal sebaceous glands.