One of the main side effects of radiation therapy to the head and neck region is altered taste sensation. This causes significant morbidity and has profound effects on the quality of life (QoL) of patients. While radiation-associated toxicities like xerostomia and dysphagia are part of large investigations, data on taste impairment is sparse.

The TASTE study sets out to further our understanding of this common side effect with the goal to prevent radiation-associated taste impairment in future patients.

In this prospective, observational multicenter study 150 head and neck cancer patients undergoing radiation therapy will be recruited. Participants will undergo repetitive (semi-) objective and subjective assessment of their taste, smell and salivary function at specific time points before, during and after radiotherapy. Primary endpoint will be patient-reported taste impairment 12 months post radiation therapy using a standardized quality of life questionnaire (MDASI-HN). Secondary endpoints will include taste impairment measured using taste strips at 12 months and 2 years post radiation therapy. Differences between subgroups (radiation side, chemotherapy, etc.) and changes over time will be assessed while adjusting for confounding factors (e.g. age, sex, smoking history). Based on the aquired data, a normal tissue complication probability model for late radiation-associated taste impairment will be develeoped.

Inclusion Criteria:

• Head and neck cancer patients
• Referred for radiation therapy with curative intent, both definitive and post-operative
• Age ≥18
• Karnofsky performance index of at least 50%
• Anticipated mean radiation dose to the taste bud bearing tongue mucosa or at least one of the major salivary glands (parotid, submandibular, and/or sublingual gland) of at the minimum 5 Gy

Exclusion Criteria:

• Pregnancy
• Pre-existing subjective complete loss of taste before start of radiation therapy
• Planning CT and radiation therapy with oral stent or spacer
• Partial or total glossectomy which impairs taste assessments of at least one side of the tongue or impairs contouring of the taste bud bearing tongue mucosa on the planning CT
• Inability to follow instructions related to study procedures or inability to fill in the questionnaires
• Inability to provide informed consent

Adult head and neck cancer patients referred for radiation therapy with curative intent, both definitive and post-operative