Craig R. et al. - Photobiomodulation and Oral Complications of Head and Neck Cancers: An Umbrella Review

This umbrella review compiled 131 systematic reviews focusing on oral and dental complications of head and neck cancers. Photobiomodulation is associated with a reduction in oral mucositis when used as supportive care—not as a cancer treatment—but the majority of the included reviews have low or very low methodological quality.

What this study measured

Treatments for head and neck cancers result in a high burden of oral complications that affect eating, speech, and quality of life. The authors sought to review all available data and assess the strength of existing systematic reviews.

An umbrella review occupies the top of the evidence hierarchy: it synthesizes systematic reviews rather than individual trials. The authors searched MEDLINE, Embase, the Cochrane Database of Systematic Reviews, and Scopus on June 19, 2025, selecting systematic reviews published in 2015 or later that focused on adults. The study follows JBI and Cochrane guidelines, is reported according to PRISMA 2020, and is registered under PROSPERO CRD420251063188. Methodological quality was assessed using AMSTAR-2, and the overlap among the primary studies was quantified using the corrected covered area.

Key Findings

The landscape described is that of a field that has been extensively studied but remains fragmented.

• 131 systematic reviews were included, most of which were rated as having low or critically low confidence according to AMSTAR-2.
• The most frequently reported complication is oral mucositis, followed by xerostomia, dysphagia, trismus, dental caries, and dysgeusia.
• Osteoradionecrosis is reported less frequently than the previous conditions.
• Photobiomodulation is associated with a reduction in oral mucositis.
• Intensity-modulated radiation therapy is associated with a reduction in xerostomia and mandibular osteoradionecrosis.

Due to the heterogeneity of the data, the results were summarized narratively by domain, without statistical aggregation.

How photobiomodulation works for this indication

In oncology, photobiomodulation is used exclusively as a supportive therapy. It aims to limit the side effects of treatments, not to act on the tumor. In oral mucositis, the mechanisms discussed in the literature link the absorption of red and near-infrared light by mitochondrial chromophores to a modulation of mucosal inflammation and support for epithelial repair.

This umbrella review does not test these mechanisms. It notes that the available systematic reviews point toward a reduction in oral mucositis, while highlighting the methodological weaknesses of the evidence supporting this finding.

Limits You Should Know

The main limitation is the quality of the included reviews. Most are rated as having low or critically low certainty according to AMSTAR-2, which inherently weakens the conclusions of an umbrella review, whose strength cannot exceed that of its sources. The authors themselves describe the evidence base as fragmented and of low certainty.

The overlap of primary studies across reviews, quantified by the corrected covered area, means that the same trials are included in multiple reviews, which can give a misleading impression of an abundance of data. Finally, photobiomodulation is just one of many interventions examined here, and the summary provides no quantified effect estimate attributable to it. Therefore, no quantitative conclusions can be drawn from it.

What This Means in Practice

This study confirms the role of photobiomodulation in the management of oral mucositis, an indication for which it has the most extensive body of evidence in supportive oncology. At the same time, it highlights that the overall level of evidence in this field still has room for improvement and that higher-quality prospective studies with standardized outcome measures are needed.

For a person being treated for head and neck cancer, photobiomodulation can only be considered as part of supportive care, prescribed and supervised by the oncology team. It does not treat cancer and is not a substitute for any therapeutic protocol.

Frequently Asked Questions

Does photobiomodulation treat cancer?

No. It is used solely as supportive care to alleviate certain side effects of treatments, such as oral mucositis. It has no proven antitumor effect and must be administered under the supervision of the healthcare team.

What is an umbrella journal?

This is a synthesis of systematic reviews, not of individual trials. It provides an overview of a field, but its reliability depends entirely on the quality of the reviews it includes.

What are the most common oral complications following head and neck cancer?

In this review, oral mucositis ranks first, followed by xerostomia, dysphagia, trismus, dental caries, and dysgeusia. Osteoradionecrosis is reported less frequently.

Reference

Craig R, O’Kane R, Rodriguez J, Scambler S, Conway D, Gallagher J. Oral and dental complications and management in head and neck cancer patients: An umbrella review. Journal of Dentistry, 2026;171:106731. PMID 42082093. Read 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.