Malignant spiradenoma: report of two cases and literature review.

Spiradenoma is a benign skin adnexal neoplasm that usually appears as a solitary nodule in any area of the body. There have been only 33 reports on malignant transformation of a benign eccrine spiradenoma since the first description by Dabska in 1972. Most cases have originated on a long-standing cutaneous lesion. These tumors can behave in an aggressive fashion, and some have led to the patient's death. We report 2 new cases of this rare neoplasm affecting 2 men, 92 and 72 years of age, comment on the clinical and pathologic features of our cases, and review the literature concerning this lesion.