Arbabi-Kalati, F., Arbabi-Kalati, F., & Moridi, T. (2013). Evaluation of the effect of low level laser on prevention of chemotherapy-induced mucositis. Acta Medica Iranica, 51, 157–162.

To evaluate the efficacy of low-level laser therapy for prevention of chemotherapy-induced mucositis and xerostomia

Patients were randomized to receive the laser or sham procedure. The laser group had laser therapy prior to each episode of chemotherapy with a 630-nm laser with a dose of 5 J/cm². Patients in the sham control group underwent procedures with the laser unit turned off. All patients received the same instruction for ongoing oral care and underwent mucous and salivary health assessment by an oral medicine specialist prior to beginning chemotherapy, after two weeks, and then every two weeks until the end of chemotherapy treatment. Severity of pain, mucositis, and xerostomia was assessed at these times, and observers were blinded to patients’ study group assignments. Data were collected for 14 weeks.

• The study reported on 48 patients.
• The mean patient age was 45.6 years, with a range of 17-79 years.
• The sample was 50% male and 50% female.
• Cancer diagnoses were lung, lymphoma, gastrointestinal (GI), skin and breast. Patients with head and neck cancer were excluded.

This was a single-site, outpatient study conducted in Iran.

Patients were undergoing the active antitumor treatment phase of care.

This was a randomized, double-blind, sham-controlled study.

• The World Health Organization (WHO) mucositis grading was used.
• A late effects of normal tissues subjective, objective, management, and analytic (LENT-SOMA) four-point scale was used to measure xerostomia.
• A visual analog scale (VAS) was used to measure pain.

In the laser group, over the course of the study, 8.3% of patients experienced grade 2 mucositis and none experienced a higher grade of mucositis, compared to 91.6% of patients in the control group who developed grade 2 or higher mucositis (p = 0.001). By week two, xerostomia intensity was significantly lower in the laser group than the control group (p < 0.005). Across all time points, pain intensity in the laser group was significantly lower (p = 0.001). Difference in pain was substantial, with a mean of 0.7 in the laser group compared to 6.8 in the control group at week 2. The magnitude of these differences in pain intensity was large at all study assessment times.

Findings showed that provision of low-level laser treatment was effective in preventing chemotherapy-induced mucositis, xerostomia, and associated pain.

• The sample size was small with fewer than 100 patients.
• The chemotherapy agents used and the schedule given were not described. 
• Laser treatment was done prior to each chemotherapy administration, and the actual number of treatments given was not clear.
• The actual risk of mucositis development in both groups was not clear.

The results here support the effectiveness of low-level laser treatment for prevention of chemotherapy-induced mucositis. The actual number of laser treatments given was not clear. One of the difficulties in evaluating laser evidence for prevention of mucositis is the different treatment schedules and doses used in the research. Further research to identify the most effective laser dosages and schedules would be helpful to facilitate clinical translation of this evidence.