Â鶹ӳ»­

Selenium is a supplement taken daily by millions in hopes of protection against cancer and a host of other diseases. However, it has proven to be of no benefit in reducing a patient¡¯s risk of developing lung cancer, either a recurrence or second primary malignancy, according to results of a decade-long, international Phase III clinical trial.

¡°Several epidemiological and animal studies have long suggested a link between deficiency of selenium and cancer development,¡± says Daniel Karp, M.D., professor in the Department of Thoracic/Head and Neck Medical Oncology.

From 2000 to 2009, the international NCI-sponsored Phase III study enrolled 1,522 stage I non-small cell lung cancer patients, all of whom had their tumors surgically removed and were cancer-free for at least six months post-surgery.

The study was halted early after an interim analysis revealed that the progression-free survival was superior in the placebo arm. The researchers did find that in a small group of lung cancer patients who had never smoked, selenium provided a small benefit. However, the size of the group of patients, 94, was too small to be statistically significant.

¡°Our results demonstrate that selenium is not an effective chemoprevention agent in an unselected group of lung cancer patients, and it¡¯s not something we can recommend to our patients to prevent a second cancer from developing or recurring,¡± Karp says. ¡°These findings also remind us that people who never smoked may represent a unique disease and should be an area for special consideration for research focus.¡±

Reported in June at the 2010 annual meeting of the .