Pedroso M.N.M. et al. - Photobiomodulation, Oral Mucositis, and Quality of Life in Head and Neck Cancers: A Systematic Review and Meta-Analysis

In patients being treated for head and neck cancer, photobiomodulation is associated with a reduced risk of severe oral mucositis and severe oral pain. The authors note that the certainty of the evidence ranges from very low to low.

What this study measured

This systematic review with meta-analysis evaluated five outcomes in patients treated for head and neck cancer: oral mucositis, xerostomia, salivary flow, oral pain, and quality of life. Six databases were searched through April 2025, with only randomized controlled trials included. A total of 33 articles describing 30 trials and 1,748 participants were included. The pooled estimates are based on a three-level mixed-effects meta-analysis, reported as relative risk (RR) and standardized mean difference (SMD). The abstract does not mention a PROSPERO number. One point to note from the outset: photobiomodulation is studied here as supportive care to limit the adverse effects of anticancer treatments. It is by no means a treatment for cancer.

Key Findings

Two criteria indicate a clear effect, a third indicates a fragile effect, and two others show no difference.

• Mucite orale sévère : RR 0,46 (IC 95 % 0,29 à 0,71 ; p < 0,001), en faveur de la photobiomodulation
• Douleur buccale sévère : RR 0,35 (IC 95 % 0,23 à 0,53 ; p < 0,001)
• Salivary flow rate: SMD 0.75 (95% CI 0.03 to 1.46; p = 0.044), statistically significant but with a very wide confidence interval
• Xerostomia: SMD -0.07 (95% CI -0.47 to 0.33; p = 0.646), no effect observed
• Quality of life: SMD 1.06 (95% CI –0.03 to 2.14; p = 0.060), non-significant difference

The benefits regarding oral mucositis and quality of life remained consistent across the various protocols.

How photobiomodulation works for this indication

The mechanism remains hypothetical and has not been tested here. Red and near-infrared light is thought to be absorbed by cytochrome c oxidase, an enzyme in the mitochondrial respiratory chain. This absorption is believed to increase ATP production and modulate signaling via reactive oxygen species. In mucosa damaged by radiation therapy, this would result in reduced oxidative stress and inflammation, increased proliferation of keratinocytes and fibroblasts, and improved microcirculation, which would also explain the reduction in pain.

Limits You Should Know

These limitations are significant, and the authors do not downplay them. The certainty of the evidence ranges from very low to low, and most trials have a high risk of bias. The study protocols vary widely from one study to another, making it difficult to recommend specific parameters. Finally, two outcomes that matter to patients—perceived dry mouth and quality of life—do not differ significantly from the control group: a null effect remains consistent with these data.

What This Means in Practice

Photobiomodulation is already included in several international guidelines for supportive care in head and neck cancer, and this review supports this approach regarding severe mucositis and pain. It makes no mention of survival or tumor progression, which were not studied here. The abstract does not specify wavelengths, power levels, or the number of sessions. Any implementation is at the discretion of the healthcare team, in consultation with the oncologist and radiation oncologist.

Frequently Asked Questions

Does photobiomodulation treat mucositis caused by radiation therapy?

No, this is not a curative treatment. In this meta-analysis of 30 randomized trials, it is associated with a reduced risk of severe oral mucositis (RR 0.46). It is a supportive measure, used in conjunction with cancer treatments and not in place of them.

Does photobiomodulation help relieve dry mouth after head and neck cancer?

The data do not show this. Regarding self-reported xerostomia, the difference is not statistically significant (SMD -0.07; p = 0.646). Measured salivary flow, on the other hand, improves (SMD 0.75), but with a very wide confidence interval, which calls for caution.

Can photobiomodulation have an effect on the tumor?

This issue is not addressed in the meta-analysis, which focused on comfort and quality of life. It remains a topic of debate in the literature. Any use in a person with cancer must be approved by their oncology team.

Reference

Pedroso MNM, et al. Effects of photobiomodulation on oral mucositis, oral pain, xerostomia, salivary flow rate, and quality of life in patients with head and neck cancer: a systematic review and meta-analysis. Supportive Care in Cancer, 2026. PMID 41880047. View the study on PubMed

This summary is provided for informational purposes only and does not constitute medical advice. Photobiomodulation is not a substitute for prescribed treatment. Consult a healthcare professional.