The lung cancer database project at the National Cancer Center, Japan: Study design, corresponding rate and profiles of cohort

Background: The lung cancer database project was established in 1999 at the National Cancer Center Hospital East, Japan, as an ongoing project to integrate data on various factors in lung cancer patients. The aim of the project was to construct a large-scale cancer registry for lung cancer that would contribute to basic research and clinical research in the future. Methods: Between July 1999 and July 2004, consecutive lung cancer patients were recruited into this project. The baseline survey consisted of self-administered questionnaires concerning various demographic data, health habits and psychological factors. Medical information was obtained from the patients' medical charts. Urine specimens and blood samples were collected, and DNA was extracted from blood lymphocytes. Results: Out of the 2506 patients who were asked to participate in the project, 2036 (81%) patients with newly diagnosed, untreated primary lung cancer were enrolled. The final analytic cohort consisted of 1995 patients. Virtually all of the 1995 patients (corresponding rate, 99%) completed the questionnaires on demographic data and health habits. The corresponding rates for the questionnaires on psychological factors and dietary habits were 99 and 94%, respectively. In a follow-up survey conducted to determine vital status as of December 2004, a total of 1051 patients (53%) had died and 44 patients (2%) were lost to follow-up. Conclusions: This paper overviews the rationale for initiating the lung cancer database project, Japan. This database should prove useful for researchers examining the pathogenesis of lung cancer and may contribute to the formulation of a framework for cancer treatment.