Spiradenomas in Brooke-Spiegler syndrome.

Brooke-Spiegler syndrome is an autosomal dominantly inherited disease characterized by the development of multiple trichoepitheliomas and cylindromas. Among other neoplasms that may also occur in Brooke-Spiegler syndrome are basal cell carcinomas and spiradenomas. Spiradenomas and cylindromas have so many features in common that they have been regarded as variants of the same neoplasm. This assumption was supported by the occurrence of both types of lesions in Brooke-Spiegler syndrome. We report a case of Brooke-Spiegler syndrome in which spiradenomas were found in the immediate vicinity of trichoepitheliomas and in continuity with follicles. Because of the embryonic relationship between follicles and apocrine glands, these features indicate that spiradenomas are apocrine neoplasms. We conclude that Brooke-Spiegler syndrome is an inherited disease that affects the folliculosebaceous apocrine unit.