Selenium therapy in patients with precancerous and malignant oral cavity lesions: preliminary results.

Baseline selenium (Se) levels in serum samples were collected from 22 patients with precancerous and 19 with malignant oral cavity lesions as well as from 13 healthy controls of the same geographic areas. Mean serum Se levels were 105, 101, and 77.03 ng/ml in the precancerous, controls, and malignancy groups, respectively. A statistically significant difference (p less than 0.005) was found between the neoplastic and both the precancerous and control groups. After careful clinical evaluation, precancerous patients received three 4-week cycles of Se, in either inorganic or organic form. Of the 22 precancerous patients entering the study, 18 were available for evaluation of clinical response. The analysis of serum Se variations revealed that serum Se levels tended to increase after the first and second cycles and then gradually returned to baseline values. At the end of the therapy, there were two complete responses (CR), five partial responses (PR), six minor responses (MR), and five stable diseases (SD) with an objective response (CR + PR) of 38.8%. Progression after suspension of therapy occurred in 7 of 18 patients; this may indicate the need of a longer treatment period with this essential trace element.