Relationship Between Pathologic Risk Of Gastrointestinal Stromal Tumors And CT Manifestation

Objective:By retrospectively analyzing the CT signs of gastrointestinal stromal tumors of different risks,the correlation between CT findings and pathological immunohistochemistry is explored,so as to preliminarily assess the risk of GIST by CT imaging findings and guide preoperative staging.Method:CT imaging data of 62 patients diagnosed with gastrointestinal stromal tumors by surgical pathology were collected in our hospital and all received abdominal MSCT enhancement scan.We adopted the risk grading standard set by the National Institutes of Health(NIH)in 2008.There are four levels: extremely low-risk,low-risk,moderate-risk,and high-risk.The CT image analysis includes tumor location,size,morphology,growth pattern,density,and enhancement pattern,etc.The relationship between gastrointestinal stromal tumors of different risks and CT signs is analyzed by comparing tumor immunohistochemistry results with CT imaging findings.Result: Extremely low-risk,low-risk,moderate-risk and high-risk were 5 cases,20 cases,11 cases and 26 cases respectively.The number of cases occurring in the stomach,small intestine and colorectal was 44,12 and 6 respectively.The risk of stromal tumors occurring in the intestine was significantly higher than that of stromal tumors occurring in the stomach.The positive rate of CD117 expression in gastrointestinal stromal tumors was 98.40%,the positive rate of DOG-1 expression was 96.84%,the positive rate of CD34 expression was91.91%,the positive rate of Ki-67 expression was 91.93%,and the positive rateof SMA expression was 30.67%.There were no statistical differences between CD117,DOG-1,CD34,Ki-67,SMA and risk grading.The larger the maximum diameter of the tumor,the higher the risk associated with liquefactive necrosis and heterogeneous enhancement;the smaller the tumor diameter,the lower the risk,without liquefactive necrosis and with homogeneous enhancement.GIST of different risks has statistical differences in maximum diameter of the tumor,liquefaction,site of onset,enhancement pattern,etc(P < 0.05),but GIST of different risks has no statistical differences in the calcification,growth pattern,degree of enhancement and CT value of each stage(P >0.05).Conclusion : There are certain differences in CT imaging findings of gastrointestinal stromal tumors of different risks.The maximum diameter,liquefaction and enhancement pattern of the tumor contribute to the preoperative and non-invasive risk grading of GIST,but there is no significant difference in calcification,growth pattern and degree of enhancement.