A RANDOMIZED, CONTROLLED CLINICAL-TRIAL TO EVALUATE THE EFFECTS OF ZINC-SULFATE ON CANCER-PATIENTS WITH TASTE ALTERATIONS CAUSED BY HEAD AND NECK IRRADIATION

BACKGROUND. In uncontrolled clinical trials, the administration of ora l zinc sulfate has been reported both to prevent and correct taste abn ormalities in cancer patients receiving external radiotherapy (ERT) to the head and neck region. METHODS. Eighteen patients were randomized to receive either zinc sulfate tablets (a dose of 45 mg) or placebo ta blets three times a day at the onset of subjective perception of taste alterations during the course of ERT and up to 1 month after ERT term ination. Taste acuity was determined by measuring detection and recogn ition thresholds for four taste qualities. Intolerance of zinc sulfate or placebo administration was investigated, and the oral cavity was e xamined. All the evaluations were studied prior to, at weekly interval s during, and 1 month after ERT administration. RESULTS. Taste acuity for one or more taste qualities was already impaired before ERT. Durin g ERT treatment, taste alterations were experienced at least once for a minimum of 3 of the 8 measured thresholds by 100% of the patients, a nd 33.3% of the patients became aware of some alteration within the fi rst week of treatment. The patients treated with placebo experienced a greater worsening of taste acuity during ERT treatment compared with those treated with zinc sulfate. One month after ERT was terminated, t he patients receiving zinc sulfate had a quicker recovery of taste acu ity than those receiving placebo. Statistically significant difference s between the two groups emerged for urea detection and sodium chlorid e recognition thresholds during ERT treatment and for sodium chloride, saccharose, and hydrogen chloride recognition thresholds after the te rmination of ERT treatment. CONCLUSIONS. This pharmacologic therapy is effective and well tolerated; it could become a routine in clinical p ractice to improve the supportive care of patients with taste alterati ons resulting from head and neck cancer. (C) 1998 American Cancer Soci ety.