Zinc, vitamins A and E, and retinol-binding protein in sera of patients with cancer of the larynx.

Serum vitamin A concentrations were measured in 22 patients with laryngeal cancer and found to be significantly lower than those of patients of similar age with either nonmalignant laryngeal or other than laryngeal diseases. The levels of vitamin A in the patients with laryngeal cancer, but not in the controls, significantly correlated with serum concentrations of retinol-binding protein (RBP) and zinc. It is suggested that low levels of zinc might reduce the synthesis of RBP and thus reduce the mobilization of vitamin A from the liver stores.