Photobiomodulation in Radiodermatitis in People With Breast Cancer

This study is a Randomized Controlled Superiority Clinical Trial involving individuals diagnosed with breast cancer and indicated for adjuvant radiotherapy at Hospital do Câncer III of the National Cancer Institute (HCIII/INCA) in Rio de Janeiro. All individuals attending HCIII/INCA for their first consultation for adjuvant radiotherapy for breast cancer will be recruited to assess eligibility criteria for the study. Those deemed eligible will receive detailed explanations regarding the study objectives, treatment groups, adverse effects, and the voluntary nature of participation through the Informed Consent Form (ICF). Upon agreeing and signing the ICF, they will undergo an initial assessment and be randomized into one of the following groups: Active Photobiomodulation Group (intervention) or Placebo Photobiomodulation Group (control).

Randomization will follow a 1:1 allocation ratio between the two groups and will be conducted using sealed, opaque envelopes in blocks of ten patients, each containing an allocation code (five codes for Active Photobiomodulation Group and five codes for Placebo Photobiomodulation Group). This method was chosen to prevent biases related to therapist or participant preferences regarding the intervention. The participants will be informed about their assigned group and the follow-up procedures throughout radiotherapy and up to three months after treatment. All assessments, interventions, and data collection will be performed by trained and qualified professionals.

At the beginning of radiotherapy, all participants will receive guidance on skin care, specific home exercises for the upper limbs, and maintaining their usual physical activities, following the institutional standard of care.

Sociodemographic characteristics (age, race/skin color, education level, marital status, and per capita income) and clinical data (comorbidities, physical activity, tobacco and alcohol consumption, body mass index, physiotherapy follow-up, clinical staging, cancer treatment history, post-operative scar complications, and oncologic treatment-related complications) will be collected from physical and electronic medical records.

For data analysis, descriptive and comparative analyses will be performed between the intervention groups concerning selected variables and primary outcomes. Measures of central tendency and dispersion will be determined for continuous variables, and frequency distribution will be used for categorical variables. Outcome evaluations (primary and secondary) will follow an intention-to-treat analysis. The Kolmogorov-Smirnov test will be used to assess data normality. Chi-square tests will analyze categorical outcomes and will be presented in absolute and relative numbers. Student's t-tests will analyze parametric continuous outcomes and will be presented as mean and standard deviation, while the Mann-Whitney test will be used for non-parametric data, presented as median and minimum-maximum values. A significance level of p\<0.05 and a 95% confidence interval will be considered for all analyses, which will be performed using SPSS (Statistical Package for the Social Sciences) version 24.

This research will not impose any financial burden on participants, as assessments will be conducted during routine consultations or treatment sessions, and additional data will be collected from electronic and/or physical medical records. The intervention materials (Antares photobiomodulation device by IBRAMED®, two protective glasses for the operator and patient, power cable, fuse, and operation manual) will be provided to the Clinical Epidemiology Applied to Oncology research group (on loan from IBRAMED® during the study period). Other office supply costs will be covered by the researchers responsible for the study.

• Incidence, intensity and modulation of pain assessed using the Visual Analog Scale (VAS) over 5 months after the start of adjuvant radiotherapy [Time frame: Evaluations will be performed in baseline and each photobiomodulation intervention (which lasts an average of 5 weeks), as well as at 30 days and 3 months after the end of radiotherapy.]
• Characteristics and intensity of pain assessed by the Pain DETECT questionnaire over 5 months after the start of adjuvant radiotherapy [Time frame: Evaluations will be performed in baseline once a week during treatment (which lasts an average of 5 weeks), as well as at 30 days and 3 months after the end of radiotherapy.]
• Pain components assessed by the McGILL questionnaire over 5 months after the start of adjuvant radiotherapy [Time frame: Evaluations will be performed in baseline, once a week during treatment (which lasts an average of 5 weeks), as well as at 30 days and 3 months after the end of radiotherapy.]
• Incidence and severity of edema/lymphedema over 5 months after the start of adjuvant radiotherapy. [Time frame: Assessments will be conducted at the baseline and end of radiotherapy treatment, as well as at 30 days and 3 months after its completion.]
• Superficial sensitivity of the irradiated skin assessed by esthesiometry over 5 months after the start of adjuvant radiotherapy [Time frame: Assessments will be conducted at the baseline and end of radiotherapy treatment, as well as at 30 days and 3 months after its completion.]
• Functionality of the upper limb on the irradiated side assessed by the Disability of Arm, Shoulder, and Hand (DASH) Questionnaire over 5 months after the start of adjuvant radiotherapy. [Time frame: Evaluations will be performed in baseline , 30 days and 3 months after the end of radiotherapy.]
• Skin quality over 5 months after the start of adjuvant radiotherapy, analyzed by thermography [Time frame: The assessment will begin one week after the first radiotherapy session and will be repeated once a week during the treatment (which lasts on average 5 weeks), as well as 30 days and 3 months after the end of radiotherapy.]
• Health-Related Quality of Life assessed by the EORTC QLQ-C30 (3rd version) and EORTC QLQ-BR23 questionnaires over 5 months after the start of adjuvant radiotherapy. [Time frame: Assessments will be conducted at the baseline and end of radiotherapy, as well as at 30 days and 3 months after its completion]
• Sleep quality according to the Pittsburgh Sleep Quality Index (PSQI) over 5 months after the start of adjuvant radiotherapy [Time frame: Assessments will be conducted at the baseline and end of radiotherapy, as well as at 30 days and 3 months after its completion]
• Satisfaction and impact of photobiomodulation on participants' health condition at the end of radiotherapy [Time frame: Approximately 5 weeks from the start of radiotherapy (21 days)]
• Safety and tolerability to photobiomodulation [Time frame: The assessment will begin one week after the first radiotherapy session and will be repeated once a week during the treatment (which lasts on average 5 weeks), as well as 30 days and 3 months after the end of radiotherapy.]
• Interruption of radiotherapy [Time frame: Throughout radiotherapy]