The quality of life and the occurrence of dysphagia in patients with head and neck cancer following combined oncological treatment ABSTRACT Introduction. The localisation of head and neck carcinomas influences the functions of speech, breathing, and swallowing, which, in turn, directly affect the patient's quality of life. The poor prognosis associated with tumours of this type indicates that aggressive combined therapy protocols, including surgery, chemotherapy, and radiotherapy, should be implemented. Such treatments commonly cause acute toxicity and short-and long-term swallowing complications. Therefore, even though they can contribute significantly to survivorship, these treatments reduce the quality of life. The aim of this study was to analyse the influence of applied combined oncological treatments on the occurrence of dysphagia in patients with head and neck cancer and on their quality of life. Results. A statistically significantly worse subjective evaluation of the quality of life was observed in the patients with dysphagia, who had undergone surgery with radiotherapy, compared to those who had not had surgery (p = 0.03). A statistically significantly worse subjective quality of life evaluation was found in patients who had the most locally advanced tumours (T4) (p = 0.04) as well as the highest stages of the disease (S3 and S4) (p = 0.04). A statistically significantly worse subjective quality of life with dysphagia was also seen in patients who had chemoradiotherapy in comparison to those who had radiotherapy alone (p = 0.01). A statistically significantly worse subjective quality of life with dysphagia was observed in the patients whose tumours were localised in the oral part of the pharynx and larynx compared to those patients with other tumour localisations (p = 0.02). A statistically significantly worse subjective quality of life with dysphagia was identified in the patients who had a higher dose of radiation (exceeding 45 Gy) in the upper oesophageal sphincter compared to those patients who had a lower dose (below 45 Gy) in the UES (p = 0.01).Conclusions. In patients with dysphagia, surgical treatment negatively impacts their subjective quality of life. Moreover, the pattern of radiation therapy affects the quality of life in patients with dysphagia.A radiation therapy plan that spares the upper oesophageal sphincter by using a dose of less than 45 Gy may prevent dysphagia. Dysphagia is also associated with tumour localization, tumour stage, and local advancement of the disease.