Review effectiveness of low-level laser therapy (LLLT) in the curative treatment of oral mucositis (OM) in patients receiving cancer therapy. A systematic review with meta-analysis was performed using Medline, Embase, and Cochrane Library databases according to PRISMA guidelines, to identify randomized controlled trials (RCT) on OM in patients during and/or after cancer therapy and in which the therapeutic approach was LLLT, with wavelengths between 632 and 970 nm. We considered grade of OM as a dichotomous variable (such as an improvement or not in severe OM on the seventh day of therapy), with the analysis of subgroups of adult patients or children and adolescents and as a continuous variable with determination of the time for the complete resolution and the subgroup analysis occurred with the strata of the samples by treatment only with chemotherapy or chemotherapy and radiotherapy. This paper's protocol was registered a priori at https://www.crd.york.ac.uk/PROSPERO . We found five RCT (total of 315 patients) with adequate methodology. LLLT was effective, presenting a 62% risk reduction of severe mucositis on the seventh day of evaluation (RR = 0.38 [95% CI, 0.19-0.75]). When we analyzed subgroups, RR was 0.28 (95% CI 0.17-0.46) in the adult studies and 0.90 (95% CI, 0.46-1.78) in the studies with children and adolescents. We demonstrated a mean reduction of 4.21 days in the time of complete resolution of OM (CI - 5.65 to - 2.76) in favor of LLLT. There is moderate evidence that LLLT is effective in resolving OM lesions in adult patients undergoing cancer therapy. LLLT demonstrates potential for decreasing the resolution time of OM lesions by approximately 4.21 days.
Keywords: Cancer therapy; Low-level laser therapy; Low-level light therapy; Oral mucositis; Therapeutics.