Optimal Screening interval for Gastric Cancer in Japan

Abstract

Annual gastric cancer screening has been recommended for residents over the age of 40 in Japan. We conducted a cost-effectiveness study in order to determine an optimal screening interval in both genders using a cohort model. Hypothetical cohorts of 100, 000 asymptomatic individuals aged 40 were assumed to have taken part in each strategy with a follow-up period of 20 years. In order to evaluate both the cost and effectiveness of the gastric cancer screening, a Markov modeling process was used. The incremental cost per year-of-life saved in gastric cancer screening, compared to no screening, illustrates a tendency toward a higher cost per year-of-life saved in both, shorter than and longer than 3-year screening intervals. Our results indicate that the recommended method of annual screening represents the least cost-effective option regarding both genders. The incremental cost per year-of-life saved of annual screening strategy was 2, 764, 000 yen (25, 127) for males and 3, 753, 000yen (34, 118) for females, compared to no screening. The figures of the incremental cost per year-of-life saved in the three year screening interval at 1, 670, 000 yen (15, 182) for males and 2, 431, 000yen (22, 100) for females clearly show this strategy as the most efficient solution in both genders, compared to no screening. However, the screening program on annual basis is not considered to be less efficient than other screening programs so far. The cost-effectiveness of gastric cancer is decreasing as its incidence decreases. It is very important for policy makers to pay attention to the incidence of diseases targeted by screening programs and to evaluate screening interval. J Epidemiol, 1995; 5 : 67-74.