Objective To investigate the feature of c-kit gene mutation in gastrointestinal stromal tumor （GIST） and its correlation with clinicolpathology， molecular targeted therapy，and prognosis. Methods The related literatures about the molecular genetic mechanism of GIST were reviewed. Results The c-kit gene mutation， which is prevalent in GIST， may be the early genomic events， and they are not the independent prognostic factor. However， different molecular subtype as a new indicator to regulate biological behaviors and assess prognosis of GIST is still controversial. Conclusions The study of genotype in GIST has advanced our understanding of pathogenesis， evaluating the prognosis and conducting treatment optimization. However， subsequent work remains to be done.
Objective To investigate the surgical treatment effect for patients with gastrointestinal stromal tumor (GIST) of the rectum and its clinical characteristics. Methods The medical records of 22 patients who had undergone surgery for GIST of the rectum between March 2003 and February 2010 in this hospital were analyzed. Results There were 14 males and 8 females with a median age of 51 years (range 27－81 years). There were 12 patients without symptoms, 10 patients with clinical symptoms, included: hematochezia 4 cases, difficult defecation 2 cases, shape of defecate change 2 cases, crissum pain 1 case, times of defecate increase 1 case. Course of disease was 2 weeks-18 months with average 6 months. All patients underwent curative resection: in form of abdominoperineal resection in 3 patients, transanal excision in 8 patients, Mason operation in 8 patients, and transanal endoscopic microsurgery in 3 patients. The median tumor size was 3.1 cm (range 0.4－18.5 cm). The diameter of tumor lt;2.0 cm was 11 cases, 2.1-5.0 cm was 8 cases, 5.1-10.0 cm was 2 cases, gt;10.0 cm was 1 case. Twentyone of 22 cases were positive for CD117, 18 cases positive for CD34, 5 cases positive for αsmooth muscle actin (SMA), and 2 cases positive for Desmin. Local recurrence or hepatic metastasis developed in 2 patients with average 26 months of follow-up (range 1 month to 7 years), and who were then treated with imatinib for more than 1 year. Conclusions The primarily treatment of rectal GIST is surgical. Imatinib therapy is effective against local and systemic recurrent GIST of the rectum.