Objective To investigate the values of various CT signs in the diagnosis of gastric cancer with extraserosal invasion. Methods The preoperative CT images of 173 patients with gastric cancer, underwent radical gastrectomy in our hospital between Jan 2015 and Dec 2016, were selected and retrospectively analyzed. Based on the operative and pathological findings, all patients were then divided into the positive group with extraserosal invasion (96 cases) and the negative group without extraserosal invasion (77 cases). The diagnostic efficacy of related CT signs, including signs of bright strings, coarseness, stripes, bulges and nodules of serosal surface, perigastric fat haziness and vascular anomaly, between the two groups were analyzed for further comparison. Results The occurrence rates of CT signs of bright strings, coarseness, stripes, bulges and nodules of serosal surface, perigastric fat haziness and vascular anomaly in the positive group were 35.42%, 96.88%, 86.46%, 64.58%, 40.63%, 68.75% and 26.04%, respectively, which were significantly higher than those in the negative group (all P<0.05). Among the above mentioned diagnostic CT signs of extraserosal invasion of gastric cancer, the CT sign of bright strings had the highest specificity (97.40%) and positive predictive value (94.44%), coarse serosal surface had the highest sensitivity (96.88%) and negative predictive value (93.88%), and stripes of serosal surface offered the highest consistent rate, odds ratio and area under ROC curve (83.24%, 12.767, 0.828; P<0.001). Area under the ROC curve of joint diagnosis of multiple CT signs for extraserosal invasion was 0.927 (P<0.001). Conclusions The CT signs of bright strings, coarseness, stripes, bulges and nodules of serosal surface, perigastric fat haziness and vascular anomaly all have diagnostic values for the extraserosal invasion of gastric cancer. The diagnostic performance of stripes of serosal surface might be much better, and combination of multiple CT signs could further improve the diagnostic accuracy. |