The Role of [18F]-FDG-PET/CT and PET/MRI in the Management of Head and Neck Squamous Cell Carcinoma

Head and neck cancer is the sixth leading cancer seen wordwide. By far, the most common histological type is squamous cell carcinoma (SCC), accounting for 95% of cases. Approximately 2%–9% of all head and neck squamous cell carcinoma will present with cervical lymph node metastases without clear evidence of a primary tumor site. Pre-therapeutic work-up of head and neck squamous cell carcinoma requires clinical evaluation, panendoscopy with biopsy, and cross-sectional imaging. [18F]-FDG-PET/CT has significantly improved diagnosis and prognosis assessment in patients with head and neck SCC, by providing combined metabolic and morphological information, improving patient management. Following implementation of first PET/MRI scanners in radiology and nuclear medicine imaging centers, use of PET/MRI is now slowly evolving, and a few studies have been published on its use in patients with head and neck SCC. The objectives of this educational abstract is to: I. Brief review of relevant head and neck anatomy. To describe where most head and neck SCCs arise, and the key prognostic factors at initial presentation. II. Review of the role of FDG-PET/CT and FDG- PET/ MRI in the initial stating of head and neck SCC, along with the potential prognostic significance of pretreatment [18F]-FDG-PET standardized uptake value (SUV) in SCC of the head and neck. III. Review of the current literature on the diagnostic performance of FDG-PET/CT and FDG- PET/MRI in the detection of unknown primary tumors in head and neck region. IV. Assessment of the value of FDG-PET/CT and FDG- PET/MRI for radiotherapy planning as well as for response assessment.