Aggressive angiomyxoma: findings on CT and MR imaging.

OBJECTIVE: Aggressive angiomyxoma is a benign tumor affecting the pelvis and perineum, predominantly in women. Because of its variable presentation as a soft mass in the vulva, perianal region, buttock, or pelvis, the tumor is often clinically misdiagnosed and initial surgery is usually unsuccessful in extirpating it. This study describes the imaging features of these tumors. CONCLUSION: Aggressive angiomyxomas display unusual growth patterns of translevator extension with growth around perineal structures. Both CT and MR imaging show the transdiaphragmatic extent of these tumors. High signal intensity on T2-weighted MR images may reflect the myxomatous stroma of these tumors.