Unexpected granular cell tumor in abdominal wall: case report and literature review.

Granular cell tumors (GCTs) are uncommon benign neoplasms deriving from Schwann cells of the peripheral nerve fibers. Although these tumors can be found anywhere in the body, the most frequent site is the tongue, followed by the chest wall and the arm. The abdominal wall is an extremely rare site for GCTs. These tumors are generally asymptomatic and have a slow growth rate. Today, thanks to their immunoreactivity to S-100 and CD68, the differential diagnosis is more straightforward than in the past. We report on a young patient affected by a GCT located in the upper third of the right rectus abdominis muscle. En bloc excision through a diamond-shaped skin incision allowed us to make a correct histological diagnosis, which was confirmed by the immunohistochemical findings. GCT, which is very rare in abdominal wall muscles, should be considered in the differential diagnosis, and surgical excision is the treatment of choice.