Background. Gastrointestinal stromal tumours (GISTs) are the most common mesenchymal tumours of the digestive tract. These tumours can not be simply divided into benign and malignant forms. There is a continuum from benign to malignant forms. The tumour size and mitotic activity have strong influence on GISTs behaviour. Tumour behaviour also varies according to the site of the origin. The site of the tumour origin can be anywhere along the digestive tract, in the mesentery or omentum. GISTs are mainly benign tumours, about 70-80%, usually found in the gastric wall. We report a case of 70-year old female with gastric form of GIST.
Case report. The patient has undergone abdominal ultrasound (US) because of a palpable lump in the epigastrium, which mainly revealed hyperechogenic round mass with small hypoechogenic areas in the central part. On the abdominal computed tomography (CT) a large expansive mass with heterogeneous structure was depicted in the gastric wall. The mass had higher attenuation coefficients on the periphery and lower in the central part. During the surgery the large exophytic tumour of the gastric wall has been found. The diagnosis of gastric GIST has been obtained after the patohistologic and imunohistochemical analysis.
Conclusions. Gastrointestinal stromal tumours may be the statistically rare tumours (0.1%-0.3% of all gastrointestinal tumours) but when we have the patient with a round, mainly exophytic mass on the wall of the gastrointestinal tract or peritoneum, GIST must be taken into consideration. Cross-sectional imaging methods like US and CT allow the preoperative diagnosis of the tumour and staging.
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