Most used photobiomodulation dosimetry parameters to treat oral mucositis after preconditioning for hematopoietic stem cell transplantation: systematic review and meta-analysis

Parameter reproducibility in photobiomodulation therapy (PBMT) is still scarce in literature for the management of oral mucositis (OM). This study aimed to identify the most used PBMT dosimetry parameters (DP) and their efficacy in OM management after preconditioning for hematopoietic stem cell transplantation (HSCT). This research was conducted according to the PRISMA guidelines. The search for primary studies was in PubMed/MEDLINE, Web of Science, Embase, BVS, and Cochrane Library. Gray literature was verified on BDTD-Ibict and Open Gray. A total of 1044 studies were identified. Nine met the eligibility criteria for qualitative assessment and 7 for meta-analysis. The studies involved 396 patients submitted to preconditioning for HSCT, 211 with PBMT and 185 without PBMT in the OM management. The WHO scale was the most used to assess OM degree. The most used parameters were 660-nm wavelength, 40-mw power, 0.16-J energy, 1-W/cm² power density, 4-J/cm² energy density, and 0.04-cm² spot size. The meta-analysis demonstrated that PBMT decreased the severity of OM, with a protection factor 20% higher than the control group (without PBMT), and when the parameters are similar to the DP mentioned, the protection factor increases to 94%. These most used DP with similarity seem to be a therapeutic strategy for the management of OM in this population.