Objective: To study the clinicopathologic features and immunoprofile of angiomyofibroblastoma (AMF) with emphasis on differential diagnosis.
Methods: Seven vulvar, two vaginal and one perineal angiomyofibroblastomas were evaluated by light microscopy and immunohistochemistry. The immunohistochemical studies were performed on paraffin-embedded sections using the standard ABC method with a panel of antibodies.
Results: Angiomyofibroblastoma predominantly occurred in middle-aged women in the genital region, especially in the superficial area of the vulva. Clinically, most of the tumors presented as slowly growing painless masses and were often diagnosed as Bartholin's gland cysts. Histologically, the tumors were all well-circumscribed and characterized by alternating hypocellular and hypercellular areas with abundant thin-walled blood vessels. The tumor cells were bland and spindle-shaped or epithelioid and tended to concentrate around the vessels or cluster in small nests. Immunohistochemically, the tumor cells expressed vimentin and estrogen receptor protein in all 10 cases and desmin in 9 cases. Three cases showed weak or focal immunoreactivity to alpha-smooth muscle actin and muscle specific actin. All ten patients were treated by local excision. Follow-up showed a benign course with no signs of recurrence.
Conclusions: Angiomyofibroblastoma is a distinctive neoplasm that has a propensity to occur in the female genital tract. Recognition of this entity is important to avoid misdiagnosis with other vulvar angiomyxoid neoplasms.