Primary gastric non-Hodgkin's lymphoma in a population-based registry.

BACKGROUND: The incidence of primary gastric non-Hodgkin's lymphoma (NHL) appears to have increased worldwide in recent years, and this seems to be confirmed by large-sample population studies. METHODS AND RESULTS: We derived our data from the Lombardy Cancer Registry, which provides the incidence of cancer in the province of Varese, Northern Italy. From 1978 to 1987 we identified 3261 cases of gastric neoplasms, 119 of which were gastric NHL: 32 (1.87%) from 1978 to 1982, and 87 (5.32%) from 1983 to 1987. The difference in the age and sex standardized incidence trend between these two time periods was statistically significant (p < 0.001). The overall survival rate of the 112 evaluable patients was 54% at 5 years and 45% at 10 years. A multivariate analysis was performed. Age (p < 0.0005), clinical stage (p < 0.04) and therapy (p < 0.0005) were found to be significant prognostic factors for survival. CONCLUSIONS: This study stresses the utility of prospective randomized clinical trials that could indicate the optimal management of patients with primary gastric lymphoma.

High incidence of other neoplasms in patients with low-grade gastric MALT lymphoma.

BACKGROUND: Low-grade gastric MALT lymphoma is an uncommon tumour for which a close association with chronic Helicobacter pylori infection has been suggested. However, given the rarity of MALT lymphoma of the stomach despite the high prevalence of H. pylori infection, it seems plausible that genetic host factors might play a fundamental role in gastric lymphomagenesis. PATIENTS AND METHODS: We retrospectively reviewed the medical records of 83 patients with low-grade gastric MALT, all of whom resided in a geographic area (southern Switzerland and northern Italy) where the incidence of gastric tumours appears to be uncommonly high. RESULTS: One or more additional cancers were observed in 17 of 83 patients (20%, 95% CI 12% to 31%) for a total of 23 tumours. Of these, 5 were diagnosed prior to, 12 concomitantly with, and 7 after the gastric MALT lymphoma. Eleven patients had a single additional solid tumour (13%, 95% CI 7% to 22%); 3 patients had non-Hodgkin's lymphoma and one had Hodgkin's disease. Multiple additional cancers were present in 3 cases. Nine of 83 patients have died and 8 of them of a second cancer. CONCLUSIONS: Unexpectedly an extraordinarily large number of patients with other malignancies was observed in this series. The reasons for this finding are still unknown, but genetic alterations are speculated to play an important role.