Serological response to Helicobacter pylori in gastric and non-gastric cancer.

1. We aimed to evaluate the seroprevalence of Helicobacter pylori (H. pylori) in gastric cancer, non-gastric cancer and outpatients by ELISA and iso-electric focusing, and to compare histology and serology for H. pylori in gastric cancer and outpatients. 2. In 124 patients with gastric cancer, 78 patients with non-gastric cancer and 110 outpatients, H. pylori seroprevalence was assessed by ELISA and isoelectric focusing. Gastric cancer and outpatients underwent endoscopy with biopsies. 3. Seroprevalence by ELISA was significantly higher in gastric cancer compared with non-gastric cancer (84% versus 56%, P < 0.001) but not with outpatients (84% versus 74%). Iso-electric focusing detection of H. pylori was comparable to ELISA: 85, 51 and 75% in gastric cancer, non-gastric cancer and outpatients respectively. Oligoclonal iso-electric focusing was significantly more frequent in gastric cancer compared with non-gastric cancer and outpatients: 69% versus 45 and 46% respectively, P < 0.01. The reliability of H. pylori detection by antral biopsy was significantly lower in gastric cancer compared with outpatients: 36% versus 74% (P < 0.001). In gastric cancer, ELISA and iso-electric focusing were significantly more reliable than histology in H. pylori detection (84 and 85% versus 36% respectively) (P < 0.001). 4. Serological immune response to H. pylori in gastric cancer, non-gastric cancer and outpatients seems different both quantitatively and qualitatively; serology was more reliable than histology in detection of H. pylori in gastric cancer.

Helicobacter pylori in patients with gastric and nongastric cancer.

OBJECTIVES: To compare the seroprevalence of Helicobacter pylori in gastric and nongastric carcinoma patients and to investigate the relationship between H. pylori, gastric cancer site, and histological type. METHODS: In a 24-month period, 307 gastric cancer patients (male/female: 185/122; age range 19-94 yr, mean 69 yr) were investigated by serology (IgG to H. pylori), histology, and urease test for H. pylori. One hundred and seventy-seven gastric cancers were in the antrum, 98 were in the corpus, and 32 were in the fundus; 227 were intestinal and 80 were diffuse type. In the same study period, we assessed the H. pylori seroprevalence in 162 patients with nongastric carcinoma (lung n = 41, breast n = 42, genitourinary n = 41, GI tract n = 22, others n = 16) (male/female: 84/78; age range 31-81 yr, mean 56 yr). RESULTS: The overall seroprevalence of H. pylori in gastric cancer and in nongastric cancer was 82 and 56%, respectively (p < 0.001). In asymptomatic blood donors (age range 55-65 yr) and in dyspeptic patients older than 60 yr, a seroprevalence of 55 and 58% was found, respectively, which is significantly lower (p > 0.001) than the gastric cancer patients but similar to the nongastric cancer population. No difference was found in the H. pylori status according to the gastric cancer site (83, 82, and 81% in the antrum, corpus, and fundus, respectively). Two hundred and twenty-seven gastric cancers [185 (81%) H. pylori-positive] were found to be of an intestinal type and 80 [66 (82%) H. pylori-positive] of a diffuse type (not significant). No age-related difference (below and above 60 yr) in H. pylori prevalence was observed within each cancer population, and, in both age groups, the seroprevalence of infection was higher in gastric cancer patients (86 and 81%) than in nongastric cancer patients (56 and 56%) (below and above 60 yr, respectively). CONCLUSION: H. pylori seroprevalence is significantly higher in gastric cancer compared with nongastric cancer patients. No differences were observed in H. pylori seroprevalence according to gastric cancer site or histological type. The higher H. pylori seroprevalence in gastric cancer patients is not age related.