[Panfolliculoma. Clinical and immunohistochemical findings in 4 cases].

Panfolliculoma is a rare benign neoplasm showing morphological similarities to the trichogenic trichoblastoma of Headington and the trichoblastoma of Ackerman. Eight patients have been previously reported; we add four additional patients. Their ages ranged from the 2nd to the 6th decade. The neoplasms were primarily situated on the head and the trunk. Clinical examination revealed a skin colored or red, dermal cystic nodule. The histological appearance of the panfolliculoma was characterized by symmetry, sharp circumscription and regular aggregations of cells, which were in parts solid or cystic. Additionally, follicular germs and papillae, matrical, inner and outer rooth sheath differentiation were identified. These varied forms of follicular differentiation were confirmed by the immunohistochemical expression of cytokeratins in different epithelial cells. Panfolliculoma is a benign neoplasm with proven morphological and immunhistochemical follicular differentiation.