Photobiomodulation reduces severe oral mucositis (RR 0.46) and pain (RR 0.35) in head and neck cancer patients

This systematic review and meta-analysis evaluated the effects of photobiomodulation on oral mucositis, oral pain, xerostomia, salivary flow rate, and quality of life in patients with head and neck cancer. The analysis included 33 articles describing 30 randomized controlled trials, with a total of 1748 patients. The literature search was conducted up to April 2025. Pooled estimates were calculated using a three-level mixed-effects meta-analysis, reporting risk ratios (RR) and standardized mean differences (SMD).

The results demonstrated that photobiomodulation significantly reduced the risk of severe oral mucositis (RR 0.46, 95% CI: 0.29-0.71, P<0.001) and the risk of severe oral pain (RR 0.35, 95% CI: 0.23-0.53, P<0.001) when compared with control groups. A significant improvement was also observed for salivary flow rate (SMD 0.75, 95% CI: 0.03-1.46, P=0.044). However, no statistically significant effects were found for xerostomia (SMD -0.07, 95% CI: -0.47-0.33, P=0.646) or quality of life (SMD 1.06, 95% CI: -0.03-2.14, P=0.060). The authors note that the benefits for oral mucositis and quality of life were consistent across different photobiomodulation protocols.

The authors conclude that photobiomodulation appears to be a promising supportive care intervention for reducing severe mucositis and oral pain, while potentially improving salivary flow rates and preserving quality of life. However, they emphasize critical limitations: the certainty of the evidence ranged from very low to low, and most included studies presented a high risk of bias. Therefore, the findings should be interpreted with caution.

For people undergoing treatment for head and neck cancer, severe mouth sores and pain can be debilitating, making it hard to eat, drink, and talk. A major review of 30 clinical trials, involving over 1,700 patients, looked at whether a non-invasive light therapy could help. This therapy, called photobiomodulation, uses specific wavelengths of light to stimulate healing.

The analysis found that compared to standard care, the light therapy significantly reduced the risk of developing severe oral mucositis (the painful mouth sores) and also significantly reduced the risk of experiencing severe oral pain. It also showed a significant improvement in salivary flow rate, which can help with dry mouth. However, the therapy did not show a significant effect on patients' reported feelings of dry mouth (xerostomia) or on their overall quality of life scores.

The researchers conclude that photobiomodulation appears promising for reducing these specific, painful side effects. However, they strongly caution that the certainty of this evidence is currently low, and many of the studies had flaws, so more high-quality research is needed before firm recommendations can be made.