Photobiomodulation for Oral Mucositis and Functional Impairments During Hematopoietic Stem Cell Transplantation

It refers to the maximal degree of oral mucositis developed after stem cell transplantation. It will be recorded daily from the first day after stem cell transplantation up to the day 20 after transplantation). The World Health Organization (WHO) oral mucositis scale will be used. Scores range from 0 (no mucositis), 1 (pain/erythema), 2 (erythema, ulcers; can eat solid foods), 3 (ulceration, requiring only a liquid diet), to 4 (oral feeding is not possible). The higher the grade, the worse the mucositis.

It refers to the perceived level of pain related to oral mucositis from a numeric scale (0 to 10), where 0 means "no pain" and 10 "the worse possible pain". Higher scores means more pain.

It is the maximal isometric strength of the handgrip that will be measured in KgF with Hydraulic Hand Dynamometer (Jamar Digital Plus®).

The exercise capacity of an individual as measured by endurance (maximal exercise duration and/or maximal attained work load) during an EXERCISE TEST. It will be assessed with the 2-Minute Walking Test is a functional test that assesses an individual's aerobic capacity and is used as a performance measure.

It is the ability to carry out daily tasks and perform physical activities in a highly functional state, often as a result of physical conditioning. Physical fitness will be evaluated with the 30-Second Sit and Stand (SST30') assesses the ability to rise from a chair and sit back down, as well as the strength and functionality of the lower limbs.

Health related quality of life is a generic concept reflecting concern with the modification and enhancement of life attributes, e.g., physical, political, moral, social environment as well as health and disease. Quality of life will be assessed using the validated and widely used instrument in the oncology population undergoing hematopoietic stem cell transplantation, the Functional Assessment of Cancer Therapy-Bone Marrow Transplant questionnaire.

Number of hospitalization days/bed days from the day of admission to medical discharge

The number of days that the patient required analgesic medication (opioids) and receives it to alleviate oral mucositis pain from the onset of oral mucositis according to World Health Organization criteria until medical discharge.

The body mass index is a person's weight in kilograms divided by the square of height in meters. It will be obtained from the patient's clinical file. Higher values mean malnutrition due to body weight excess and lower values mean malnutrition due to underweight. It will be classified according to World Health Organization: underweight (<18.5), normal weight (18,5 to 24.9), overweight (25 to 29.9) and obesity (>30).

Nutritional status has been defined as an individual's health condition as it is influenced by the intake and utilization of nutrients. The evaluation of the nutritional status will be through the Subjective Global Evaluation. This scale classifies patients in: well nourished, mildly/moderately malnourished, or severely malnourished.

It correspond to the mean of daily calorie intake (kcal/day) of the patient. It will be obtained from the hospital record. Higher values mean higher calorie intake.

It is the circumference of the arm (cm) that will be measured in the mean point between the distance of olecranon and acromion with relaxed arm and elbow flexed at 90 degrees.

Corresponds to the thickness of the triceps region (mm). It will be assessed with a skinfold caliper. Higher values indicate more body fat.

To estimate patient´s acceptability, a visual analogue scale from 0 to 10 will be used only with intervention group, where 0 refers to no acceptability, 5 to a moderate level of acceptability and 10 to an optimal level of acceptability. Furthermore, the register of adherence to the PBM sessions will serve as an indicator of this acceptability, since the professional who performs the intervention will consult the patient every day regarding their willingness to receive PBM and will note on the record sheet.

It to refers to how long, in days, did it take to engrafment of the hematopoyetic stem cell transplant. Engraftment is the process by which hematopoietic stem cells (HSC) make their way (homing) to free bone marrow (BM) niches where they can find optimal conditions to survive and proliferate.