Aggressive angiomyxoma in males. A report of four cases.

Aggressive angiomyxoma (AAM) is a rare, locally infiltrative but nonmetastasizing tumor of the pelvic and perineal soft tissues that occurs almost exclusively in adult females. The authors describe four cases of AAM in adult males that arose in the scrotum. There was some histologic variation among the tumors. One case was focally hypercellular around the blood vessels, two were more densely cellular throughout, and one had cystic degeneration. Three of the tumors were widely infiltrative, and one of the four tumors recurred locally. The clinicopathologic features of these cases are similar to those of AAM occurring in females. In either sex, AAM should be distinguished from benign myxoid tumors with a low risk of local recurrence and fully malignant myxoid tumors with distant metastatic potential.