A Randomized Multi-Intervention Trial to Inhibit Precancerous Gastric Lesions in Lingu, Shandong Province

Summary

The Division of Cancer Epidemiology and Genetics is conducting a collaborative randomized multi-intervention trial with the Beijing Institute for Cancer Research to evaluate the etiologic role of Helicobacter pylori, garlic, and certain micronutrients in the multi-step process of gastric carcinogenesis. The primary endpoint will not be cancer, but rather the precancerous lesions severe chronic atrophic gastritis, intestinal metaplasia, and dysplasia. The study is designed to detect a stabilizing or mild decrease in the expected age-related progression of precancerous lesions over the course of the trial. Thus the trial can be considered a study of the potential inhibitors of the process of gastric carcinogenesis. The trial will also provide an evaluation of therapy for H. pylori, including an assessment of reinfection rates, a critical need for formulating strategies for infection control in China and other developing countries. Participating in the trial are approximately 3400 adults aged 35-70 who were part of an ongoing survey of precancerous gastric lesions in 13 Linqu villages in Shandong Province. Linqu appears to be an ideal setting for the trial since stomach cancer rates are among the highes in the world, precancerous gastric lesions are prevalent, and the population is stable and well characterized. These individuals will be randomly assigned (taking H. pylori positivity into account) into 8 intervention groups according to a 2(3) factorial design. The interventions are: 1) initial treatment of H. pylori infection with ameprazole and amoxicillin followed by 2) daily supplementation with a combination of alpha-tocopherol, vitamin C, and selenium; and 3) daily supplementation with garlic extracts. No serious side effects have been seen from any of the interventions to date. The study staff will continue to monitor for possible adverse reactions and the population will receive routine medical care follow-up throughout the course of the trial. As part of the ongoing study in Linqu, all participants received an endoscopic exam in the fall of 1994. Repeat gastroscopic exams with biopsies at 7 standard gastric sites will be conducted during March to May, 1999 and March to May, 2003 to detect early cancers and to evaluate gasatric mucosal status. The subjects will be categorized according to the most advanced lesions detected in all biopsies and assigned a severity score. The three major endpoints for analysis will be: 1) prevalence of dysplasia or cancer 2) prevalence of sever chronic atrophic gastritis, intestinal metaplasia, dysplasia, or cancer; and 3) average severity score.

Timeline

Start

1995-07-01

Primary completion

1996-06-10

Completion

1996-06-10

Publications

• Background Correa P. Human gastric carcinogenesis: a multistep and multifactorial process--First American Cancer Society Award Lecture on Cancer Epidemiology and Prevention. Cancer Res. 1992 Dec 15;52(24):6735-40.
• Background You WC, Blot WJ, Chang YS, Ershow AG, Yang ZT, An Q, Henderson B, Xu GW, Fraumeni JF Jr, Wang TG. Diet and high risk of stomach cancer in Shandong, China. Cancer Res. 1988 Jun 15;48(12):3518-23.
• Background You WC, Blot WJ, Li JY, Chang YS, Jin ML, Kneller R, Zhang L, Han ZX, Zeng XR, Liu WD, et al. Precancerous gastric lesions in a population at high risk of stomach cancer. Cancer Res. 1993 Mar 15;53(6):1317-21.
• Su XQ, Yin ZY, Jin QY, Liu ZC, Han X, Hu ZQ, Zhang L, Ma JL, Li ZX, Zhang Y, Zhou T, Liu WD, You WC, Pan KF, Shi L, Li WQ. Allium vegetable intake associated with the risk of incident gastric cancer: a continuous follow-up study of a randomized intervention trial. Am J Clin Nutr. 2023 Jan;117(1):22-32. doi: 10.1016/j.ajcnut.2022.10.017. Epub 2022 Dec 20.
• Guo Y, Li ZX, Zhang JY, Ma JL, Zhang L, Zhang Y, Zhou T, Liu WD, Han ZX, Li WQ, Pan KF, You WC. Association Between Lifestyle Factors, Vitamin and Garlic Supplementation, and Gastric Cancer Outcomes: A Secondary Analysis of a Randomized Clinical Trial. JAMA Netw Open. 2020 Jun 1;3(6):e206628. doi: 10.1001/jamanetworkopen.2020.6628.
• Li WQ, Zhang JY, Ma JL, Li ZX, Zhang L, Zhang Y, Guo Y, Zhou T, Li JY, Shen L, Liu WD, Han ZX, Blot WJ, Gail MH, Pan KF, You WC. Effects of Helicobacter pylori treatment and vitamin and garlic supplementation on gastric cancer incidence and mortality: follow-up of a randomized intervention trial. BMJ. 2019 Sep 11;366:l5016. doi: 10.1136/bmj.l5016.

Drugs

Indications