Oton-Leite, A.F., Silva, G.B., Morais, M.O., Silva, T.A., Leles, C.R., Valadares, M.C., . . . Mendonca, E.F. (2015). Effect of low-level laser therapy on chemoradiotherapy-induced oral mucositis and salivary inflammatory mediators in head and neck cancer patients. Lasers in Surgery and Medicine, 47, 296–305.

DOI Link

Study Purpose

To evaluate the effect of low-level laser therapy (LLLT) on the severity of oral mucositis (OM) and the release of salivary molecules (TNF~a, IL-1b, IL6, IL10, TGF-b, EGF< FGF< VEGF< MMP2/TIMP2, and MMP9/TIMP2) during chemoradiation in patients with head and neck cancer

Intervention Characteristics/Basic Study Process

All patients received radiation therapy (RT) treatments over seven weeks with a minimum dose of 50 Gy to the oral cavity and cisplatin at 100 mg/m2 every 21 days. Patients were randomized to two groups. The experimental group received LLLT (660 nm, 25 mw output power in a continuous wave at a fluence of 6.2 J/cm2 energy per point of 0.24 J for 10 seconds per point) while the control group received sham therapy (patients wore glasses so they would not know if laser light was on or not). LLLT and sham therapies were administered by the same operator. All patients received standard oral healthcare, antifungals, and analgesics when needed. OM was evaluated weekly by the same trained dentist who was blinded to the randomization. Saliva samples were obtained at one point before chemoradiotherapy and at three points during the treatment on days 7, 21, and 35 of RT. Spitting specimens and unstimulated saliva collections were obtained, and both were analyzed for salivary inflammatory mediator levels.

Sample Characteristics

  • N = 25  
  • AGE = 10 were aged greater than 60 years, and 15 were aged less than 60 years
  • MALES: 84%, FEMALES: 16%
  • KEY DISEASE CHARACTERISTICS: Head and neck cancer (nine oral cavity, seven pharynx, and nine oropharynx)
  • OTHER KEY SAMPLE CHARACTERISTICS: In the laser group, three patients died during the course of the study, two from pneumonia and one from hemorrhagic complications (not explained). In the control group, two patients dropped out of treatment. The sample started with 30 patients, and only 25 completed treatment.

Setting

  • SITE: Single site  
  • SETTING TYPE: Unknown
  • LOCATION: Brazil

Phase of Care and Clinical Applications

  • PHASE OF CARE: Active treatment

Study Design

Randomized, double-blinded, placebo-controlled clinical trial

Measurement Instruments/Methods

  • The severity of OM was rated according to the National Cancer Institute (NCI) and World Health Organization (WHO) mucositis grading scales.

Results

OM grades in both scales were significantly lower in the laser group than in the control group at RT sessions 7, 21, and 35 (p < 0.05). In the control group, levels of IL-6 followed the clinical course of OM until the peak (ulcerative phase) at RT session 21. In the LLLT group, salivary IL-6 concentrations decreased significantly at the end of RT (session 35, p = 0.032). Regarding the proinflammatory cytokines IL-1B and TNF-a, there was no statistically significant difference between the two groups. In regard to the anti-inflammatory cytokines IL-10 and TGF-b, no statistically significant difference between the groups was found. For the growth factors analyzed, FGF levels decreased after the ulcerative phase of OM in the laser group. This was statistically significant at session 35, corresponding to wound healing (p = 0.038).

Conclusions

LLLT reduced OM in the experimental group when compared to the control group. This study added to the growing body of literature demonstrating that LLLT is an effective intervention for OM in patients receiving treatment for cancer.

Limitations

  • Small sample (< 30)
  • Key sample group differences that could influence results
  • Other limitations/explanation: Six patients in the laser group had T3 or T4 disease while 10 patients in the control group had T3 or T4 disease. There was no mention of comorbid conditions such as diabetes, which might affect healing time and salivary concentrations. There were no limits on medications taken by the participants, which could have affected the outcomes.

Nursing Implications

Reducing OM can have a distinct impact on patients' quality of life, pain control, and ability to complete chemoradiation in a timely manner. Nurses have daily interactions with patients to assist them through the completion of therapy. This study contributed to the growing body of literature demonstrating that LLLT is an effective intervention for OM.