Evaluation of head and neck cancer

Flourine-18 fluorodeoxyglucose PET, particularly when performed on a combined PET/CT scanner, provides an exciting new technique for characterising the presence, extent and biological characteristics of head and neck cancer at all phases of the diagnostic evaluation process. As a functional imaging technique, it is not constrained by structural changes either for diagnosis or exclusion of disease. PET/CT allows detailed and high fidelity fusion of anatomical and biochemical data, enabling detection of occult primary lesions, involvement of non-enlarged nodes and remote metastatic sites not detected by conventional techniques. This allows better selection and planning of therapy. Conversely, in the post-treatment setting, metabolic responses occur earlier than structural regression, allowing patients who have responded completely to treatment to be managed expectantly and salvage therapies to be instituted earlier in those who have not. New PET tracers are becoming available to further characterise tumour biology. Hypoxia imaging is already of potential clinical importance in this regard.