Evaluation of diagnosis methods for primary gastrointestinal stromal tumors        CAO Dong-xing*, WU Guo-hao, WANG Qing-guo, et al. *Department of General Surgery, Zhongshan Hospital，Fudan University，Shanghai 200032，China
Corresponding author: WU Guo-hao, E-mail: wu.guohao@zs-hospital.sh.cn
Abstract    Objective    To evaluate value of various techniques in diagnosis of primary GIST. Methods    The imaging data of 70 patients with GIST admitted between December 1, 2004 and May 30, 2009 at Zhongshan Hospital of Fudan University were analyzed retrospectively. The imaging data included CT scanning, endoscopy, endoscopic ultrasound (EUS) and ultrasonography (US). Results    CT findings showed eccentric in 44 patients, intraluminal in 24 patients and transmural in 2 patients. Forty-four patients were dumbbell-shaped, while 26 patients were irregular-shaped. Forty-three patients presented as well-defined, while 27 patients with unclear borders. The arterial phase attenuation showed continuous enhancement. The portal-venous phase was heterogeneous in 26 patients and homogeneous in 44 patients. There was a significant correlation between CT features and tumor grade. In endoscopy, GIST presents as a smooth normal overlying mucosa. In US, GIST was typically hypoechoic and solid masses. Conclusion    CT scan is valuable in the diagnosis, staging and treatment planning of GIST. Endoscopy and EUS contribute to the detection of mucosal lesions. Other methods help in specific cases.