Gastrointestinal stromal tumors (GISTs): analysis of 20 cases.

Background/Aims: Gastrointestinal stromal tumors (GISTs) are soft tissue sarcomas arising from the mesenchymal tissues in the gastrointestinal tract. Diagnosis, treatment and follow-up protocols of GISTs have not been exactly defined. In this study, twenty cases with GISTs treated in our clinic are examined retrospectively. Methodology: Twenty cases treated for GISTs in Izmir Atatiirk Training and Research Hospital between the years 1999 and 2004 were reviewed retrospectively. Age, gender, clinical findings, diagnostic methods, intraoperative findings, type of surgery, histopathological findings and survival of the patients were evaluated. Results: Fifteen of the cases were male (75%) and five were female (25%), with a median age of 55 years (35-80). The most frequent symptoms were abdominal pain and acute gastrointestinal bleeding. Tumors were gastric (40%), small intestinal (45%), colonic (10%) or rectal (5%). The median tumor size was 9.1 centimeters. Pathological evaluation showed that number of mitoses per 50 high-power field (hpf) was more than five in nine of 10 cases and CD-117 was positive in four of four cases. The mean follow-up period was 21 (1-72) months, and median survival was 21 (1-72) months. Conclusions: The prognosis of GIST is frequently related to the tumor size and rate of mitosis. Despite the recent demonstration of C-kit protooncogene and introduction of imatinib mesilate as a new chance in treatment, radical surgery remains to be the most effective treatment of GISTs.