Angioleiomyoma originating from the ano-rectal wall presenting as a perineal mass: a case report

Angioleiomyoma, a vascular leiomyoma is a rare, benign smooth-muscle tumor observed to occur anywhere in the body, most frequently in the lower extremities but very rarely in the digestive system. Angioleiomyoma in the hindgut is infrequent and in particular, rectal/perianal location has been observed very rarely.

We describe herein a case of a 50-year-old male patient complaining of perineal discomfort and a swelling at the level of the left ischio-rectal fossa, moderately painful. This solid mass in the left ischio-rectal space was in close relationship with the wall of the ano-rectal junction. After surgical removal and histopathology, the mass resulted an angioleiomyoma, vascular type, desmin positive, a very rare neoplasm. Extensive immune-histochemical studies are fundamental for the correct diagnosis and to rule out other mesenchymal tumors.

Angioleiomyoma is a very rare neoplasm of the gastrointestinal tract, and the fundamental problem of peri-rectal/perianal angioleiomyoma is represented by differential diagnosis from gastrointestinal stromal tumors (GISTs) and other perianal/perirectal swellings. For correct differential diagnosis, the histopathology supported by extensive immune-histochemical study adopting a panel of specific tissue markers is important. The surgical treatment is mandatory with complete excision and subsequent follow-up since local recurrence may occur.