In the immunohistochemical analysis of all patients with GIST, c-KIT (CD-117) was positive in 53/69 cases (77%), CD-34 was positive in 34/69 cases (49%), SMA was positive in 10/69 cases (14%), S-100 was positive in 15/69 cases (22%), desmin was positive in 4/69 cases (6%), L1CAM was positive in only 1/69 cases (1.5%), DOG1 was positive in 13/69 cases (19%), and vimentin was positive in 17/69 cases (25%). This evidence concerns the gene KIT and gastrointestinal stromal tumor.