Evolution of precancerous lesions in a rural Chinese population at high risk of gastric cancer

The pathogenesis of gastric cancer (GC), particularly of the intestinal typ e, is thought to involve a multistep and multifactorial process. Our object ive was to determine the rates of transition from early to advanced gastric lesions in a population in Linqu County, China, where the GC rates are amo ng the highest in the world. An endoscopic screening survey was launched in 1989-1990 among 3,399 residents aged 34-64 years with precancerous lesions diagnosed from biopsies taken from 7 standard locations in the stomach and from any suspicious sites. The cohort was subsequently followed, with endo scopic and histopathologic examinations conducted in 1994. Logistic regress ion analysis was used to estimate odds ratios (ORs) of progression to advan ced lesions of various levels of severity as a function of age, sex and bas eline pathology. The rates of progression were higher among older subjects, among men and among subjects with more extensive gastric lesions. 34 incid ent GCs were identified during the follow-up period. The Ops of GC, adjuste d for age and sex, varied from 17.1 for those with baseline diagnoses of su perficial intestinal metaplasia (IM), to 29.3, for those with deep IM or mi ld dysplasia (DYS) or IM with glandular atrophy and neck hyperplasia, to 10 4.2, for those with moderate or severe DYS, as compared with subjects with superficial gastritis (SG) or chronic atrophic gastritis (CAG) at baseline. Our prospective study of a high-risk population revealed sharp increases i n the risk of GC and advanced precursor lesions according to the severity o f lesions diagnosed at the start of follow-up. (dagger) Published 1999 Wile y-Liss, Inc.