Granular cell tumor of stomach: a case report and review of literature.

Granular cell tumor (GCT) was described for the first time by Abrikosoff in 1926. It is a relatively rare neoplasm that may occur at many sites, but most commonly in the skin or soft tissues. The occurrence of GCT in the gastrointestinal tract is rare, accounting approximately for 8% of all tumors, among which the most common site is the esophagus, whereas gastric localization is very rare. Gastric GCTs can be solitary or, more frequently, associated with other gastrointestinal localization. Although GCTs are usually clinically and histologically benign, some malignant cases have been reported. Histologically, these tumors consist of polygonal and fusiform cells disposed in compact "nests" and immunohistochemical staining for S-100 protein supports the proposed derivation from Schwann cells. A correct preoperative diagnosis of this tumor can only be made in 50% of all patients and it is always based on endoscopic biopsy. Laparoscopic or conventional wedge resection represents the treatment of choice. In this study, the authors reported a case of a 49-year-old woman with a solitary granular cell tumor of the stomach with infiltrative pattern, successfully treated with surgical resection. A review of literature is also presented with emphasis on diagnostic criteria concerning the malignant form.