IntroductionRadiotherapy (RT) is the most common nonsurgical treatment for head and neck cancer (HNC) and may or may not be combined with chemotherapy (CT). Dysphagia, characterized by impaired swallowing function, is one of the most common side effects of RT, occurring during and after RT, and may persist long after treatment. ObjectiveTo compare the evolution of dysphagia, nutritional status, and quality of life (QoL) in the periods immediately before and after RT for HNC in individuals who received only RT or combined RT/CT. MethodsProspective longitudinal observational study performed in a hospital of the Brazilian public health system. The individuals were allocated into two groups: RG (n = 20), consisting of patients who received only RT for HNC, and RCG (n = 27), who received RT plus CT. The patients were evaluated before and after RT to identify and classify dysphagia (PARD protocol), anthropometric variables (BMI, triceps skinfold thickness, arm and calf circumferences, and manual dynamometry), and QoL (QLC-30 and H&N-35 questionnaires). ResultsThe groups were homogeneous in demographic characteristics and tumor stage. RCG showed a higher proportion of worsening dysphagia severity (p < 0.01) and worsening of anthropometric assessment (p < 0.05). A negative correlation was observed between the initial-final change in dysphagia and the change in BMI for the total sample (rho=-0.379, p < 0.05). QoL worsened in most domains evaluated, but RCG showed additional worsening in the domains of global health and nausea and vomiting (p < 0.05). ConclusionRT for HNC leads to the early development of dysphagia, which can adversely affect nutritional status and QoL. Including CT in the RT regimen leads to a more accentuated worsening of the evaluated parameters.