Selenium and immunocompetence in patients with head and neck cancer

This randomized double-blind placebo-controlled study aimed to determine wh ether oral intake of 200 mu g/d of sodium selenite, a dose within the safe and adequate daily intake (50-200 mu g/d) recommended by the U.S. Food and Nutrition Board, will abrogate depressed or enhance normal-level immune fun ctions of patients receiving therapy for squamous cell carcinoma of the hea d and neck. Subjects were given one selenium/placebo tablet/d for 8 wk, beg inning on the day of their first treatment for the disease (e.g., surgery, radiation, or surgery and radiation) and their immune functions were monito red. Supplementation with selenium (Se) during therapy resulted in a signif icantly enhanced cell-mediated immunue responsiveness, as reflected in the ability of the patient's lymphocytes to respond to stimulation with mitogen , to generate cytotoxic lymphocytes, and to destroy tumor cells. The enhanc ed responsiveness was evident during therapy and following conclusion of th erapy. in contrast, patients in the placebo arm of the study showed a decli ne in immune responsiveness during therapy, which was followed, in some pat ients, by an enhancement, but the responses of the group remained significa ntly lower than baseline values. The data also show that at baseline, patie nts entered in the study had significantly lower plasma Se levels than heal thy individuals, and patients in stage I or II of disease had significantly higher plasma selenium levels than patients in stage III or IV of disease.