Spiradenocylindromas of the skin: tumors with morphological features of spiradenoma and cylindroma in the same lesion: report of 12 cases.

Twelve cases of spiradenocylindromas, which revealed features of both spiradenoma and cylindroma in the same tumor mass, are presented. Nine female patients had multiple neoplasms occurring mostly on the scalp, and two female and one male patient had a solitary cutaneous lesion. Three of the female patients with multiple cutaneous tumors had a familial history of similar cutaneous neoplasms. In one of the patient's family, the multiple cutaneous tumors were known to occur in multiple family members in four consecutive generations. One patient with multiple cutaneous lesions was known to have associated multiple kidney cysts as confirmed by computed tomography. Histologically, spiradenocylindromas are composed of intermixed areas that are either of typical spiradenoma in appearance or of typical cylindroma appearance. Apocrine and trichoepitheliomatous differentiation seen in two cases in the present series points to spiradenomas, as well as cylindromas, having complex hair follicle (folliculo-sebaceous apocrine) rather than eccrine differentiation. The presence of lymphoid tissue was a histological feature in the present series, which was prominent in all the spiradenomatous parts of the tumors and which was scanty or practically absent in all the cylindromatous parts. The selective presence of lymphocytes in spiradenoma and an absence in cylindroma suggest that spiradenomas have the unique property of attracting lymphocytes. The malignant tumors arising in three patients in the present series had the morphology of a poorly differentiated epithelioid neoplasm. Three patients died of the disease and the other patients were either free of disease or alive with disease 1-30 years on follow up.