[Solitary rectal diverticulum. A case presentation].

of tumors, and there is no evidence of any type of benefit with imatinib mesylate or other drugs that have demonstrated results of improved survival in the case of other high-risk or advanced gastrointestinal stromal or mesenchymal tumors. Tumor size and stage, cell proliferation rate and the state of the resection margins and tumor capsule are the most important prognostic factors in this type of tumors. A strict post-operative follow-up is necessary because 30% of cases may present recurrence or metastasis.Overall 5-year survival is estimated at approximately 50% in high-risk patients.