Rare case of aggressive angiomyxoma presenting as a retrovesical tumor.

Aggressive angiomyxoma (AAM) is a rare mesenchymal benign tumor that preferentially involves the pelvic and perineal regions in relatively young females. We report here a rare case of AAM presenting as a retrovesical tumor in a male patient. A 59-year-old man undergoing abdominal ultrasound examination because of benign prostatic hyperplasia was found to have a retrovesical mass. Computed tomography and magnetic resonance imaging of the pelvis showed the retrovesical tumor to be 7.4 x 6.7 cm. The tumor was resected, and diagnosed histopathologically as AAM. The patient showed no recurrence 26 months after resection. Although the majority of retrovesical tumors are considered to be sarcoma or neurogenic tumor, AAM should also be recognized as a differential diagnosis.