Hydrogastric sonography in the preoperative staging of gastric cancer

Purpose Depth of wall invasion is the main prognostic factor in gastric cancer. We studied the utility of hydrogastric sonography in the evaluation of transmural infiltration by gastric cancer. Methods Thirty‐seven patients with gastric adenocarcinoma were examined before surgery with a 5‐MHz probe after the ingestion of 100–400 ml of water (mean, 330 ml). Sonographic results were compared with pathologic classifications obtained after surgery. Results Of the 37 tumors, 15 were found at surgery to be in the antrum, 10 were in the gastric body, 5 were proximal, and 7 were diffuse. After surgery, tumors were classified as follows: 2 (5%) T1, 4 (11%) T2, 15 (41%) T3, and 16 (43%) T4. Hydrogastric sonography correctly classified 30 (81%) of the 37 tumors. Sonography was correct for 2 (100%) of the 2 T1 tumors, 2 (50%) of the 4 T2 tumors, 13 (87%) of the 15 T3 tumors, and 13 (81%) of the 16 T4 tumors. Five sonographic errors were due to understaging and 4 to overstaging. With regard to tumor site, sonographic results were correct for 4 (57%) of the 7 diffuse tumors, 3 (60%) of the 5 proximal tumors, 9 (90%) of the 10 gastric body tumors, and 14 (93%) of the 15 antral tumors. Conclusions Hydrogastric sonography is useful for preoperative evaluation of transmural infiltration by gastric cancers, particularly tumors in the antrum or gastric body. © 1999 John Wiley & Sons, Inc. J Clin Ultrasound 27:499–504, 1999.