Abstract
Oral mucositis (OM) is a commonly observed and debilitating side effect of chemotherapy and radiation therapy in patients with cancer, especially head and neck cancer. Although there is no proven therapy for the prevention and treatment of OM, zinc supplementation effectively decreases the incidence of OM. This paper provides a current and comprehensive meta-analysis of the efficacy of zinc compared with placebo/control in OM. A systematic literature review was conducted using MEDLINE and Central databases for randomized control trials (RCTs) comparing zinc supplementation (oral or rinse) with placebo/control in patients with various types of cancer undergoing chemotherapy, radiation therapy or combined chemo-radiation. The outcome was OM incidence, independent of the severity. A random-effects model was used to calculate the pooled risk ratio and subgroup analyses were performed. A total of 12 RCTs were included, containing information from 783 patients. A decrease in OM incidence was observed overall when all cancer therapies were considered. However, subgroup analyses showed that zinc did not significantly decrease the incidence of OM when studies were stratified by cancer therapy or scale/criteria used to assess OM. The results of the meta-analysis support the use of zinc supplementation in decreasing OM incidence in patients with cancer receiving chemotherapy or radiation therapy. However, the high heterogeneity between studies and the small number of studies are limitations of the meta-analysis.