Current status and future perspectives of cooperative study groups for lung cancer in Japan.

The performance of scientifically and ethically valid prospective clinical trials is the only means by which to obtain reliable clinical evidence that can improve clinical practice and thus the outcome of patients with lung cancer. The efficacy of treatment for advanced lung cancer remains limited; many cooperative study groups for lung cancer have been established in Japan since 1990s, and they have completed several landmark investigator-initiated clinical trials. This review highlights eight active Japanese cooperative study groups for lung cancer and summarizes their achievements made through clinical trials. In addition to their benefits, the existence of multiple study groups for a single disease such as lung cancer presents several challenges including the provision of infrastructure to ensure the scientific integrity of trial results, the unnecessary duplication of effort and the wasting of limited resources, and the accrual and completion of large-scale phase III trials in the shortest possible time. Collaboration among Japanese cooperative groups has recently increased in order to overcome these challenges. Although institutional barriers to the performance of such large intergroup trials remain, further harmonization and collaboration among cooperative groups will be vital in allowing Japanese investigators to make further important contributions for the development of new lung cancer therapies.