Background: A large-scale population-based cohort study would offer the best evidence of a relation between lifestyle and cancer.
Methods: The Japan Collaborative Cohort Study (JACC Study) for Evaluation of Cancer Risk sponsored by the Ministry of Education, Science, Sports and Culture of Japan (Monbusho) was established and carried out from 1988 to 1990 in 45 areas in Japan. Epidemiological information, such as demographic information, past medical history, exercise/sports activities engaged in, frequency of food intake, smoking and alcohol drinking status and so on, was collected by a self-administered questionnaire. Blood samples were collected from each participant at screening in 37 out of 45 areas to investigate risk factors of cancer relating to biochemical substances in blood. Collected sera were divided into 3-5 tubes (100-500 microL per tube) and stored at -80 degrees C. Additionally, about 5 years after the baseline survey, an interim survey regarding lifestyle changes was conducted in 31 areas. We followed the study subjects for mortality, move-outs, and cancer incidence, if possible (in 24 areas).
Results: There were 127,477 participants (54,032 men and 73,445 women) registered in the study. Of these, 110,792 subjects (46,465 men and 64,327 women), aged 40 to 79 years at baseline, were eligible for follow-up. Sera were stocked from 39,242 subjects, and interim survey was carried out on 46,650 subjects.
Conclusions: The JACC Study provides useful evidence for cancer prevention in Japan.