There are two main types of gastrointestinal connective tissue tumors: differentiated connective tissue tumors arising from smooth muscle tissue, schwanommas or fibroblastic tissue, and non-differentiated connective tissue tumors with no precise origin. Pathologically non-classifiable tumors comprise a group of real gastrointestinal stromal tumors. Stromal tumors are rare and generally develop in the stomach. Immunohistochemistry has been able to identify three entities: stromal tumors with skenoid fibers, gastoinestinal autonomic nerve tumors, and intraabdominal desmoplastic small round-cell tumors. After resection, survival is almost 50% at 5 years and depends particulary on tumors size, the presence of synchronous metastases and mitosis count.