Body composition changes in patients with head and neck cancer under active treatment: a scoping review

Background: Head and neck cancer patients have the second highest malnutrition prevalence, when compared with other oncological patients. They experience significant weight loss before diagnosis, during and after treatment, and even during the first year of follow-up. However, the prognostic value of weight loss depends on body mass index, and this may be associated with low skeletal muscle mass, masking its loss. Thus, weight loss itself poorly predicts outcome in head and neck cancer patients when compared with depleted skeletal muscle mass, illustrating the inadequacy of body mass index as an accurate method to reflect nutritional status. A synthesis is needed of the body composition changes occurring in head and neck cancer patients during treatment, as well as of the methods to assess it. Objective: The aim of this scoping review is to examine and map the body composition changes in head and neck cancer patients under oncological treatment with curative intent. A further objective is to determine which methods are used to assess body composition in these patients. Inclusion criteria: Types of participants: The current review considered head and neck cancer patients, aged 18 years or older. Concept: This scoping review considered all studies that focused on the body composition changes. Context: This scoping review considered the studies that evaluated the body composition changes in the context of treatment with curative intent. Surgical treatment approach was excluded to avoid excess heterogeneity in the data. Types of sources: This scoping review considered only published studies, with abstract available. Search strategy: A three-step search strategy was undertaken. This review was limited to studies published in English, Spanish, and Portuguese during 2000–2019. Data extraction: The data extracted included author(s)/year of publication, aims and purpose of the study, sample size, study design, type of treatment, measurement points and component(s) of body composition evaluated, body composition assessment methods, and main results/findings. Presentation of results: Head and neck cancer patients suffer from serious loss of lean body mass, skeletal muscle, or free fat mass, after treatment compared with baseline. Further, nutritional deterioration is evident and occurs up to 8–12 months after treatment. Bioelectrical impedance analysis is one of the body composition assessment tools that has the great advantage for being available on a regular basis for assessment of body composition in head and neck cancer patients. However, it cannot be recommended for clinical decision making until further validation. Conclusion: Head and neck cancer patients experience a significant depletion of lean body mass, fat-free mass, and skeletal muscle, accompanied by body fat mass, while undergoing (chemo)radiotherapy. This can be demonstrated either by triceps skinfold thickness, bioelectrical impedance analysis, dual-energy x-ray absorptiometry, or computed tomography. This loss has a remarkable impact on their survival, on their quality of life, and on the risk for post-operative complications and may result in a reduced response to cancer treatment. Thus, body composition assessment should become an integral component of the care of head and neck cancer patients, beyond weight and body mass index, and should be carried out at different times throughout treatment.