The protective effects of melatonin on blood cell counts of rectal cancer patients following radio-chemotherapy: a randomized controlled trial

PurposeWe aimed to examine the radioprotective effects of melatonin on the blood cell counts of patients with rectum cancer undergoing radiotherapy.Materials and methodsThis double-blind placebo-controlled study was conducted on 60 rectal cancer patients who were referred to Rajaii Hospital of Babolsar, Iran. An equal number of patients were randomly assigned to the control group which received placebo and study group which received 20mg melatonin a day as an intervention. The melatonin was administered 5days a week for 28days. Blood samples were taken before melatonin received on day 1 and also day 28; then, to measure the changes in blood cell counts representing our primary outcomes, the samples were analyzed by Sysmex K810i auto-analyzer.ResultsOur results showed that the platelet, white blood cells, lymphocyte, and neutrophil population reduction induced by radiotherapy were slighter or even insignificant in melatonin recipients compared to control. However, the difference between red blood cells in both groups was not significant.ConclusionOur results are indicating that melatonin could prevent or minimize the unfavorable effects of radiotherapy on blood cell count reductions by attenuating the adverse influence of radiation, probably through stimulation of cellular antioxidant potential as previously reported in animal models.Iranian Registry of Clinical Trials (IRCT)Registry No. IRCT2016021626586N1.