Molecular Imaging in Head and Neck Squamous Cell Carcinoma Patients

Abstract

Head and neck squamous cell carcinoma (HNSCC) is often diagnosed at an advanced stage, and despite intensive treatment prognosis remains poor. Accurate staging and tumor delineation are essential for determination of a personalized treatment strategy. Molecular imaging with radionuclides or fluorescent probes allows visualization of tumor biology in vivo. Positron emission tomography (PET) imaging gives whole body information with low resolution whereas optical molecular imaging has a high resolution but limited penetration and limited field of view. Therefore, PET imaging might improve staging and radiotherapy planning and optical imaging is of interest for early detection and guidance of surgical resection in HNSCC. In this chapter we describe how these techniques can be used to study the presence and distribution of specific tumor characteristics and tumor delivery of drugs. In addition, the current role of 18F-fluorodeoxyglucose (18F-FDG) PET is addressed, and non-FDG PET tracers including tracers for hypoxia and epidermal growth factor receptor (EGFR) imaging are discussed. We describe development of EGFR imaging with fluorescence and address preclinical imaging results in HNSCC models for other molecular targets, including integrin αvβ3. Adequately powered clinical trials are needed to assess the added value of molecular imaging before implementation, and standardization of techniques and endpoints is essential.