Mineral derivatives in alleviating oral mucositis during cancer therapy: a systematic review

Objectives. Oral mucositis (mouth ulcers) is a cancer therapy side effect. Costly treatment interventions are often neglected in favor of cost-effective agents. This review assessed the general efficacy of mineral derivatives (a cost-effective agent) in alleviating oral mucositis (OM) during cancer therapy compared to the standard care, or placebo-including a decision tree to aide healthcare workers. Data Sources. Electronic searches of MEDLINE via OVID, EMBASE, CENTRAL, CANCERLIT via PubMed, and CINAHL via EBSCO (year 2000 to 11 September 2014) were undertaken for randomised controlled trials. A meta-search strategy extracted content from aggregate online databases. Review Methods. Randomized controlled trials were assessed (participants, intervention, outcome, results, and risk of bias) for inclusion. The author abstracted binary and continuous data synthesised to Hedges' g in a random effects model. The primary outcome measures were severity (incidence of peak oral mucositis, duration of oral mucositis, and time to onset); secondary outcome measures were the incidence of pain, and analgesic use. Serum mineral levels, total parenteral nutrition, and adverse events were discussed. The decision tree was mapped using sensitivity, specificity, pre-test and post-test Bayesian probability. Results. 1027 citations were identified and 16 studies were included (n = 1120; mean age 49 years). Cancer therapies consisted of chemotherapy, radiotherapy, chemo-radiotherapy, or hematopoietic stem cell transplantation. Outcome mineral derivatives were zinc (n = 549), calcium phosphate (n = 227), povidone-iodine (n = 228), or selenium (n = 116). Severity was measured across variable OM grading systems: In 13 studies, individuals in treatment groups (n = 958) experienced peak OM less than controls (g = -0.47, 95% CI -0.7 to -0.2, p = 0.0006); time to OM onset was significantly delayed in treatment than controls (g = -0.51, 95% CI-0.8 to -0.2, p = 0.0002; five studies); OM mean duration, pain incidences, or analgesics use was not significant. The decision analysis favored selenium. Conclusion. The general positive effect trend suggests individuals taking mineral derivatives during cancer therapies are less likely to experience peak OM than those without. However, significant bias and heterogeneity indicates the need for developing further methods in account of diverse protocols and include novel recordings (serum mineral levels and cell signals) in estimating a uniform true effect.