Synchronous gastric adenocarcinoma and mucosa-associated lymphoid tissue lymphoma in association with Helicobacter pylori infection: comparing reported cases between the East and West.

The association of Helicobacter pylori infection with synchronous gastric adenocarcinoma and mucosa-associated lymphoid tissue (MALT) lymphoma is rare. Three Chinese patients (M:F = 1:2) who were 71, 58, and 75 yr of age were diagnosed to have gastric adenocarcinoma (2 patients) and gastric lymphoma (1 patient) on endoscopic biopsies. Distal gastrectomy was performed in all of them. Histological study of the three resected specimens revealed synchronous gastric adenocarcinoma and MALT lymphoma. H. pylori infection was found in two patients. A literature search revealed another 29 patients with synchronous tumors in whom H. pylori status was examined. Overall, H. pylori infection was found in 78% of 32 patients. The majority of lymphoma was low grade (75%) and was larger than carcinoma (81%). The majority of carcinoma (65.6%) was early. This suggested lymphoma might develop before carcinoma or the presence of MALT lymphoma might increase the risk of developing carcinoma.