Response to the Letter to the editor by Donnelly et al. regarding the article "Photobiomodulation therapy for the prevention of acute radiation dermatitis in head and neck cancer patients (DERMISHEAD trial)"

Abstract

We want to thank Donnelly et al. for the letter [1], allowing us to clarify some statements made in our paper [2]. As a general point, our research group already has a few years of experience in investigating the use of photobiomodulation therapy (PBMT) for the prevention and management of acute radiodermati-tis (ARD) in cancer patients [3-6]. For a recent narrative review on PBMT and ARD by Robijns et al., nine clinical trials investigating the use of PBMT in ARD were available for evaluation [7]. Results demonstrate that PBMT could significantly reduce the severity of ARD. The DERMISHEAD trial described in this paper is the first patient-blinded randomized controlled trial (RCT) in head and neck (HNC) cancer patients studying the effectiveness of PBMT in the prevention and management of ARD [2]. Concerning the timing of the outcome measure collection, it is true that ARD typically peaks at one to two weeks after the completion of radiotherapy (RT) [8]. We did not choose an extra follow-up moment for this study due to the extra burden for this vulnerable study population. However, it would have given us extra insight into how PBMT could affect the development of the peak acute skin reactions and the healing process of ARD. Concerning the quality of life (QoL) of the participating patients, we could not detect any significant differences between the two groups at RT dose of 40 Gy and the end of RT. The QoL of the patients was assessed by using the Skindex-16, a validated questionnaire to measure the extent the patients' life is affected by their skin condition.