Gastrointestinal mesenchymal tumors (GISTs) are malignant tumors derived from the mesenchymal tissue of the gastrointestinal tract. Compared to epithelial tumors of the GI tract, mesenchymal tumors account for a small percentage of the tumors, but among the mesenchymal tumors of the GI tract, GISTs are the most common mesenchymal-derived tumors of the GI tract whose origin is uncertain. GIST can occur anywhere from the esophagus to the anus, most often in the stomach (60%-70%), followed by the small intestine (20%-30%). However, it is not limited to the gastrointestinal region and primary foci have been identified in the colon, mesentery, omentum, liver and female vagina. The pathogenic mechanisms are: overexpression of c-kit protein (CD117) found in most GISTs, genetic c-kit gene activating mutations or platelet-derived growth factor alpha gene mutations, and c-kit proto-oncogene mutations leading to sustained activation of kit tyrosine kinase, resulting in uncontrolled proliferation of the mutated cells. Genetic analysis of malignant gastrointestinal mesenchymal tumors suggests that c-kit mutations are mostly located in exon 11, and genetic analysis is currently the only meaningful method for diagnostic evaluation and prediction of treatment outcome. The literature reports that the mutation rate of c-kit gene in GIST varies from 15% to 95%, and four c-kit mutation loci have been identified in GIST, namely mutations in exons 11, 9, 13, and 17. Among them, exon 11 mutation is the most common and its response to imatinib treatment is the best. For the management of mesenchymal stromal tumors, surgical resection is the primary and effective approach for GIST, and the first complete tumor resection is the key to improve the outcome. Since recurrence and metastasis are quite common in GIST, re-operative resection is often not curative but only symptomatic relief, and GIST is insensitive to chemotherapy and radiation, the survival rate of GIST patients was quite low before the FDA approved the introduction of imatinib for the treatment of GIST in 2002. For many patients, the use of imatinib has shifted the acute threat of a lethal malignancy to a manageable chronic condition. Imatinib is a small molecule tyrosine kinase inhibitor that blocks the downstream signaling of mutant kinases, significantly improving survival in patients with unresectable or already distantly metastatic GIST. Imatinib at 400 mg daily is the recommended first-line treatment regimen for patients with recurrent or metastatic GIST, regardless of prior surgical treatment experience. The response to treatment with imatinib is closely related to the mutation site and type of kit. Most patients who initially respond to imatinib treatment eventually develop resistance to the drug. Sunitinib has been approved in recent years for use in patients with GIST, primarily in patients who have failed to respond to imatinib treatment. Although there are few effective treatments for GIST and most recurrent cases are not curable, and the best criteria for evaluating and observing the efficacy of imatinib have not yet been determined, I believe that this is where we should strive to design more effective treatment options to overcome this solid tumor in the future.