Long-term survival of cancer patients after photobiomodulation therapy for prevention and treatment of oral mucositis

Background: Photobiomodulation therapy (PBMT) has been employed for the prevention and treatment of oral mucositis in patients with head and neck cancer undergoing treatment. However, information about the survival of patients receiving PBMT is still lacking. Therefore, the aim of this study was to correlate the survival of patients who either received or did not receive PBMT, combined with cancer treatments, and to assess whether the number of PBMT sessions had a positive impact on survival. Methods: The records of 751 patients seen at Hospital de Caridade São Vicente de Paulo diagnosed with head and neck cancer, treated by D.L.P., the sole operator of PBMT, between 2000 and 2016, were analyzed. The median survival rates were compared by analyzing diagnostic staging, the combination of cancer treatments, and the number of PBMT sessions. Correlation analyses were performed to assess the interactions between the number of PBMT sessions and survival. Results: PBMT increased survival by 55.14 %, from 1.07 (Without PBMT) to 1.66 years (With PBMT) for the total population and more significantly in Group 41 (stages III and IV, radiation therapy/chemotherapy, with more than five PBMT sessions), the median survival value of 1.83 years, which represents a 66.36 % higher survival rate. In all the analyzed populations, the larger number of sessions was associated with better survival. In terms of survival, advanced stages III and IV almost equated with stages I and II in the absence of PBMT. Conclusions: PBMT seems to interfere with the survival of patients with head and neck cancer, corroborating its recommendation for the treatment of mucositis, but further research is needed to investigate possible synergistic effects between PBMT and cancer treatments.