A chemotherapy regimen commonly used to treat non-small cell lung cancer is both more effective and more toxic in Japanese patients than in American patients, researchers reported recently at the annual meeting of the American Society of Clinical Oncologists.

The first of its kind, this analysis underscores the importance of genetic variations in medicine and points to a need for increased international collaboration in trials of new cancer treatments.

"Results of a cancer clinical trial performed in one part of the world may not necessarily hold true for populations in other regions," said lead investigator David Gandara, director of clinical research at UC Davis Cancer Center and professor of medicine at the UC Davis School of Medicine.