Analysis of gastric carcinoma growth by endoscopic ultrasonography

Abstract

Endoscopic ultrasonography (EUS) was performed preoperatively in 82 patients with gastric carcinoma (40 with early and 42 advanced malignancy). Measurements of wall thickness were performed in each case and showed good correlation with histological findings. Wall thickening was found to consist of both tumorous and accompanying ulcerous tissue. Thus, increasing wall thickness, as demonstrated by EUS, may not necessarily mean progressive tumor growth. The EUS features of gastric carcinoma were analyzed and four distinct growth patterns found: predominantly intramural (IM) or intraluminal (IL) growth with preservation (Type 1) or destruction (Type 2) of the submucosal echo-rich layer. All early carcinomas displayed the IL-type growth pattern on EUS (98% IL1-type) and 81% of advanced tumors showed IM-type features. EUS was able to differentiate between early and advanced carcinoma in 98% of cases. The EUS pattern of submucosal destruction (type IM2 or IL2) corresponded to the expanding type tumor according to Ming's histopathological classification. On the other hand, 24 of 26 infiltrative tumors according to Ming were found on EUS to have an intramural growth pattern with preservation of the submucosa (type IM1). It is concluded that EUS is highly sensitive in predicting the tumor growth pattern in gastric carcinoma, providing important additional information to the currently used TNM staging system. Measurements of wall thickness are reliable but differentiation between tumorous growth and peritumorous changes is not possible.