In the study, it was aimed to evaluate the relationship between dysphagia, which is one of the treatment complications, and the variables of respiratory performance, intraoral pressure and neck endura, and to look at the future work and rehabilitation methods of these evaluation outcomes from a different parameter.

Head and neck cancers; oral cancers, pharyngeal cancers, laryngeal cancers, salivary gland cancers, and cancers involving the skin of the head and neck region. Head and neck cancer treatment options include surgery, radiotherapy, and chemotherapy.

Dysphagia, that is, difficulty in swallowing, is a symptom that affects the quality of life, which is often neglected in patients with head and neck cancer. 40% of patients suffer from dysphagia during and after treatment. Dysphagia causes serious complications such as aspiration, malnutrition and even death, in addition to causing increased health expenditures with a decrease in the quality of life.

Swallowing and respiration are two vital functions coordinated with each other, ensuring coordination is vital.

When the respiratory-swallowing relationship was examined in HNC patients, the patient's breathing was examined through swallowing apnea, but respiratory performance was not evaluated through intraoral pressure and respiratory function test.

Swallowing dysfunctions are frequently seen in patients with head and neck cancer, both due to the pathophysiology of the disease and because the treatments applied due to the localization of the tumor affect the head and neck region, and the quality of life is low because these patients cannot reach rehabilitative approaches. In studies on the effects of chemotherapy and radiotherapy, which are included in the treatment of head and neck cancer patients, it has been proven in the literature that it causes a decrease in swallowing performance and neck endurance over time.

Based on the literature and clinical experience, it can be concluded that there is currently no "gold standard" in the evaluation or treatment of dysphagia in patients with HNC. This result is also valid for the neck endura parameter in patients with head and neck cancer. However, in a study conducted with head and neck cancer patients, it was revealed that there is a correlation between subjective and objective evaluation scales.

At the end of the study, it was aimed to evaluate the relationship between dysphagia, which is one of the treatment complications in patients, with respiratory performance, intraoral pressure and neck endura variables, and to look at the future study and rehabilitation methods from a different parameter.

Inclusion Criteria:

• Diagnosing head and neck cancer patients (larynx, nasopharynx, tongue, tonsil, parotid, retromolar trigone, lip, tongue root, hypopharyngeal cancers)
• Statement with consent considering participating in the study
• Disorders that cause obstacles due to the Function Test and intraoral passages

Exclusion Criteria:

• Presence of a chronic disease that prevents participation in the pulmonary function test and the study by the radiation oncology doctor and otolaryngologist.
• Patients with swallowing problems due to previous illness or surgery
• Acute surgical patient

Patients between the ages of 18-80 who were diagnosed with head and neck cancer voluntarily, who met the inclusion criteria and agreed to participate in the study, will be included.