Prevalência de lesões precursoras do câncer gástrico e do Helicobacter pylori em familiares de pacientes com câncer gástrico

Abstract

Infection by Helicobacter pylori, a bacterial species classified by WHO as being carcinogenic (group I) affects more than half the world population. First-degree relatives to patients with gastric cancer are at increased risk of developing gastric cancer. The present study evaluated the prevalence of precursor lesions of gastric cancer and infection by Helicobacter pylori in first-degree relatives to patients with gastric cancer as compared to controls with no family history of gastric cancer. One hundred four first-degree relatives to 40 patients with noncardiac gastric cancer were enrolled in the study and compared to 108 controls. The groups were statistically homogenous in terms of age. All patients were submitted to endoscopic evaluation and biopsy as described in the Sydney protocol. The histopathological analysis was carried out by a single, experienced pathologist blinded to the origin of the samples. Although the prevalence of atrophy and intestinal metaplasia was similar for the two groups, association with these lesions was more common among relatives than controls (p=0.021). Incomplete intestinal metaplasia was also more significant among relatives (p=0.001), as was displasia (p=0.025). The group of relatives presented a pattern of pangastritis associated with lymphoid follicles characteristic of increased risk for gastric carcinogenesis. There was no statistically significant difference between the groups with regard to the prevalence of H. pylori, though infection involving body and antrum was more prevalent among relatives (p=0.001). Our findings suggest that relatives to patients with gastric cancer present a greater prevalence of histopathological changes associated with the presence of H. pylori