Eccrine Spiradenoma

Nests of tumor cells often contain interspersed lymphocytes, as seen in the photomicrograph above. Although extremely rare, spiradenomas can undergo malignant transformation (spiradenocarcinoma). These lesions can be associated with Brooke-Spiegler syndrome which is caused by mutations in CYLD tumor suppressor gene. Features suggestive of spiradenocarcinoma include an infiltrative growth pattern and cytologic atypia.