This observational prospective clinical study aims to describe the epidemiology, management and outcome of patients with sinonasal and skull-base pathology (tumours and diseases with malignant clinical characteristics) in a tertiary otorhinolaryngology referral centre. The main questions it aims to answer are:

• what is the caseload of patients with the included pathology in our centre
• what are the results of management of these cases
• what are the epidemiological characteristics of included patients
• what is the quality of life of included patients.

Sinonasal tumours and tumours that involve the adjacent skull base are rare entities. However, their management necessitates a special knowledge of ENT areas and specifics of sinonasal anatomy and skull base. Due to the heterogeneity of pathological diagnoses of sinonasal and skull-base tumours, one of the main aims of this study is to provide epidemiological characteristics in our geographical area. Furthermore, to compare with other tertiary referral centres, we will analyse management results, which could improve the management of these diseases. Since the sinonasal area and skull base house several important neuroanatomical structures and senses, we aim to provide an analysis of the patient-reported quality of life.

Inclusion Criteria:

• sinonasal and/or skull-base cancer
• sinonasal disease expanding through the skull-base
• the patient's written informed consent

Exclusion Criteria:

• lateral skull-base disease primarily originating in the temporal bone and without central skull-base involvement

The study population will be recruited from patients referred to the tertiary otorhinolaryngology referral centre. The referral applies to the in-hospital or outpatient setting.