Prevention of acute radiodermatitis by photobiomodulation: preliminary results of a randomized, placebo-controlled trial in breast cancer patients

Abstract

Background The aim is to evaluate the effectiveness of photobiomodulation therapy (PBMT) in the prevention of acute radiodermatitis (RD) in breast cancer patients undergoing radiotherapy (RT). Study Design/Materials and Method This randomized, placebo-controlled trial enrolled 66 breast cancer patients that underwent an identical RT regime post-lumpectomy. Patients were randomly assigned to the laser (n=34) or placebo group (n=32). There were no significant differences between the two groups with respect to patient- and treatment-related characteristics. Laser or placebo was applied two days a week, immediately after the RT session, starting at the first day of RT. PBMT was delivered using a class IV MLS® M6 laser that combines two synchronized laser diodes in the infrared range (808-905 nm) with a fixed energy density (4 J/cm2). Clinical scoring of RD (Radiation Therapy Oncology Group (RTOG) grading scale) and biophysical measurements (skin hydration, transepidermal water loss (TEWL), and degree of erythema) were determined at the first day, at fraction 20 and at the end of RT. In the results section, only preliminary results of the RTOG scores are shown. Results At fraction 20 of RT, there was no significant difference between the groups in the distribution of RTOG grades (p= .524), with most of the patients presenting RTOG grade 1. Towards the end of RT, the skin reactions worsened in the placebo group (p= 0.016), while they remained stable in the laser group (p= .207). There was a significant difference in the severity of RD between the two groups (p= .021) with a larger percentage of patients experiencing RTOG grade 2 or higher (e.g. moist desquamation) in the placebo group (28.1% vs. 5.9%, for the placebo and laser group, resp.) at the last day of RT. Conclusion The preliminary results of this first randomized, placebo-controlled trial show that PBMT can prevent aggravation of acute RD in breast cancer patients.