Radiation fibrosis syndrome (RFS) is a general side effect of radiation therapy (RT) which can adversely impact patients chronically over years typically triggered by an acute inflammatory state that evolves into chronic inflammation and tissue remodeling causing lymphedema, fibrosis, pain, atrophy and organ dysfunction. Some of the side effects that encompass RFS in the head and neck (HNC) population include decreased ability to fully open the mouth (trismus), neck pain and tightness (cervical dystonia), lymphedema (swelling), difficult with speech and swallowing and salivary hypofunction. Although there is Level I evidence demonstrating the benefit of Photobiomodulation (PBM) therapy to prevent acute mucositis in HNC patients treated with RT, there is only limited data regarding its impact.

This is a clinical trial to compare active treatment (PBM-therapy) with sham control (Sham- therapy). Up to 60 patients will be randomized to the two groups with equal allocation to estimate the efficacy (soft tissue thickness) of external Photobiomodulation (PBM) with light-emitting diode (LED) planned therapy for the treatment of radiation fibrosis syndrome (RFS) in head and neck cancer (HNC) patients who have undergone radiation therapy (RT) compared with sham control.

Inclusion Criteria:

• Patients treated with radiation for head and neck cancer who are ≥ 3 months < 36 months post-RT (last RT).
• Patients who received at least 50Gy of bilateral neck RT. Subjects who received RT or concurrent chemoradiation (chemoRT) therapy for HNC are eligible.
• No evidence of disease as documented by imaging 3 months after completion of RT.
• Common Terminology Criteria for Adverse Events (CTCAE) fibrosis score ≥ 2 at enrollment.
• Patient who has body mass index (BMI) >30 at the time of enrollment may be excluded at a discretion of the principal investigator if fibrotic areas cannot be identified by clinical objective assessment of fibrosis.
• Willing to comply with all study procedures and be available for the duration of the study.

Exclusion Criteria:

• Woman who are pregnant or planning to become pregnant or breast-feeding.
• Patients enrolled on another drug or device investigational trial for prevention or treatment of LEF.
• Patients deprived of freedom, under supervision or guardianship.
• Patients unable to attend to scheduled visits due to geographical, social or mental reasons.
• Patients who received prior PBM therapy for RT toxicities in the last year;
• Patients who report being photosensitive.
• Patients who have chronic immunosuppression or are on current immunosuppressive therapies.
• Any patient who, in the opinion of the investigator, is unable or unlikely to comply fully with the study requirements or procedures for any reason.