Is photobiomodulation therapy effective in reducing pain caused by toxicities related to head and neck cancer treatment? A systematic review.

Photobiomodulation therapy (PBMT) has been considered an effective method for preventing and managing certain cancer-related toxicities in head and neck cancer (HNC) patients treated with radiotherapy and chemotherapy. However, the potential effects of PBMT on pain control and analgesia resulting from these toxicities is still controversial. The aim of this systematic review was to compile available evidence of the effects of PMBT on pain control and reduced use of analgesics in HNC patients. We searched three indexed databases: MEDLINE/PubMed, Embase, and Scopus. The databases were reviewed up to and including December 2018. Only human clinical studies in English language were selected. Information was only available for mucositis and radiodermatitis. Fifteen out of 1112 studies met the inclusion criteria (14 for oral mucositis (OM) and 1 for radiodermatitis). From the 14 studies involving the prevention and treatment of OM, 10 had the study subjects compared to a placebo group. Of these 10 studies, all but 1 showed statistically significant difference related to pain control favoring the PBMT group. The study that compared PBMT with other treatment modality showed better results in pain control with PBMT. It appears that PBMT application frequency and potency impact on pain control. The only study involving the prevention and treatment of radiodermatitis was compared to placebo arm and showed statistically significant difference related to pain control favoring the PBMT group. Seven studies compared the need of analgesic medication between PBMT and placebo groups. Of these, five studies showed that the use of analgesic medication was significantly higher in the placebo group. The current evidence supports that PBMT is effective in pain control resulting from OM and radiodermatitis and may also reduce the need for analgesics. The evidence is not yet available of the effects of PBMT in other HNC treatment-related toxicities.