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 at the annual meeting of the American Society of Clinical Oncologists in New Orleans this spring.

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

Median survival time was 12 months for the Japanese patients who received paclitaxel and carboplatin, versus 9 months for American patients receiving the same regimen. "The reasons for the increased survival among the Japanese patients remain to be determined, but the implications of this observation are of considerable interest," says lead investigator David Gandara, director of clinical research at UC Davis Cancer Center and professor of medicine at the UC Davis School of Medicine.

The U.S. trial was conducted through the Southwest Oncology Group, one of the country's largest National Cancer Institute-sponsored cancer clinical trials cooperative groups. The Japanese study was conducted through the Four-Arm Comparative Study Group. Gandara is a member of the ASCO board of directors, and serves as its secretary/treasurer. He also chairs the SWOG Lung Committee.