[Gastrointestinal stromal tumours and acute haemorrhage: description of four cases].

Gastrointestinal stromal tumours are uncommon neoplasias arising from stromal tissue of the intestinal wall. Discovery of the protooncogene c-kit and the presence of the CD117 protein on the neoplastic cells of the majority of gastrointestinal stromal tumours may suggest their possible origin from Cajal cells. The clinical symptoms of gastrointestinal stromal tumours are related to tumour size and are generally aspecific: acute or chronic bleeding, abdominal pain and palpable mass are some of the most common signs. Digestive endoscopy or US-endoscopy for gastroduodenal tumours, ultrasonography and CT scans are the procedures of choice in the evaluation of the location, size, invasion of adjacent organs and metastases. Surgery is the only curative therapy for gastrointestinal stromal tumours. Chemotherapy or radiotherapy are of no use for metastatic disease, but good results are obtained with ST1571 in advanced disease. In the absence of metastases, it is quite difficult to distinguish between benign and malignant lesions. The most important prognostic factors are number of mitoses and tumour size. We report here on 4 consecutive cases of gastrointestinal tumours, 2 gastric and 2 duodenal, which presented with acute gastrointestinal bleeding.