DAHANCA 24: Prognostic Value of 18F-FAZA in Head and Neck Squamous Cell Carcinoma (HNSCC)

Solid tumours contain varying degrees of hypoxia. Studies show hypoxia to be associated with poor local control and survival, as hypoxia is a cause of resistance to radio- and chemotherapy and the development of a more aggressive tumour. Previous attempts to measure hypoxia have been biased because the techniques have been invasive, not repeatable or difficult to apply on a routine basis. There is great interest in trying to measure hypoxia in tumours as this could lead to individualized hypoxia-modifying therapy and prediction of treatment response. Additionally the investigators' knowledge of change in hypoxia over time is limited, but of great interest as individualised treatment, such as intensity-modulated radiation therapy (IMRT) is emerging. 18F-FAZA, appears promising. It is a nitroimidazole, which gets trapped in hypoxic cells and can be detected by a positron emission therapy (PET) scan. Compared to other nitroimidazoles, 18F-FAZA has superior biokinetics and thereby is believed to provide a faster and clearer image of hypoxia. The investigators' hypothesis is that 18F-FAZA can be used as a prognostic marker in HNSCC.