Low-level laser in prevention and treatment of oral mucositis in pediatric patients with acute lymphoblastic leukemia

Photomed Laser Surg. 2013 Dec;31(12):613-8. doi: 10.1089/pho.2012.3327. Epub 2013 Nov 21.


Objective: The aim of this study was to evaluate the influence of low-level laser therapy (LLLT) on the prevention and treatment of oral mucositis (OM) in pediatric cancer patients taking methotrexate.

Background data: OM is a very common, potentially severe side effect, caused by treatment with radiotherapy and chemotherapy for cancer.

Methods: Forty patients with acute lymphoblastic leukemia, who received high doses of methotrexate, were distributed into two groups. Group A (Preventive Group) was composed of patients who received preventive laser (red-subgroup A1 or infrared-subgroup A2) for 5 days, beginning on the 1st day of infusion. Group B (Treatment Group) was composed of patients who received laser treatment only if they developed post-chemotherapy mucositis (red-subgroup B1 or infrared-subgroup B2). Laser was used at wavelengths of 660 or 830 nm with output 100 mW, power density 3.57 W/cm(2), spot size 0.028 cm(2), energy of 1 J, resulting in an energy density of 35 J/cm(2) for 10 sec in the prophylactic group, and energy of 2 J, resulting in energy density of 70 J/cm(2) for 20 sec in the therapeutic group.

Results: The percentage of patients who did not develop OM was higher in Group A (60% vs. 25%). In Group B, 3/20 patients developed grade IV OM (15%), and a significant difference was found between the two subgroups at the end of treatment (p=0.019).

Conclusions: Prophylactic laser produced a better outcome than when patients did not receive any preventive intervention, and red laser (660 nm) was better than infrared (830 nm) in the prevention and treatment of OM.

MeSH terms

  • Adolescent
  • Antimetabolites, Antineoplastic / adverse effects
  • Child
  • Child, Preschool
  • Humans
  • Infant
  • Low-Level Light Therapy*
  • Methotrexate / adverse effects
  • Precursor Cell Lymphoblastic Leukemia-Lymphoma / complications*
  • Stomatitis / prevention & control*
  • Stomatitis / radiotherapy*
  • Treatment Outcome


  • Antimetabolites, Antineoplastic
  • Methotrexate