Correlation of computed tomography features with tumor grade of gastrointestinal stromal tumor

Abstract

Objective To analyze the computed tomography(CT) features of the gastrointestinal stromal tumor (GIST) and to estimate the CT features for assisting the pathologic classification of GIST. Methods The data of fifty-eight patients with pathologically and immunohistochemically proven GISTs were collected, including 41 patients with malignant tumors and 17 patients with benign or malignant potential tumors, who underwent examination of CT for primary tumors. The effect of CT features to the classification of the GIST was analyzed. Results Malignant GISTs were significantly more common in the small intestine and rectum than in the stomach and esophagus. Fifty GISTs extending outside or among the wall, 38 of them were malignant tumors. The mean tumor size was 7.5 cm. Twenty-six were larger than 7.5 cm and 23 of them were malignant. Thirty-five had irregular surface and among them, 30 were malignant. All the benign or malignant potential tumors had clear boundary, and 19 cases of malignant GIST had unclear boundary. Forty-one of malignant GIST and 10 cases of benign or malignant potential tumors showed heterogeneous enhancement. All the malignant GIST and 10 of benign or malignant potential GIST demonstrated necrosis. Fifteen of malignant GIST demonstrated circumference invasion. Five patients had hepatic metastases and 1 had peritoneal dissemination. There were no significant differences between malignant and benign or malignant potential GIST about the tumor enhancement, tumor vessel, inner layer enhancement or ulcer. Conclusion CT plays an important role in the preoperational diagnosis and classification of GIST. Key words: Gastrointestinal stromal tumor; Pathology; Classification; Computed tomography