ORIGINAL ARTICLE CLINICAL IMPACT OF, AND PROGNOSTIC STRATIFICATION BY, F-18 FDG PET/CT IN HEAD AND NECK MUCOSAL SQUAMOUS CELL CARCINOMA Caroline A. Connell, FRANZCR, 1 June Corry, FRANZCR, 1,2 Alvin D. Milner, PhD, 3 Annette Hogg, PhD, 4 Rodney J. Hicks, FRACP, 2,4 Danny Rischin, FRACP, 2,5 Lester J. Peters, FRANZCR 1,2 1 Division of Radiation Oncology, Peter MacCallum Cancer Centre, St Andrews Place, East Melbourne, Australia. E-mail: carolineconnell@yahoo.com.au 2 University of Melbourne, Parkville, Victoria, Australia 3 Centre for Biostatistics and Clinical Trials, Peter MacCallum Cancer Centre, St Andrews Place, East Melbourne, Australia 4 Centre for Molecular Imaging, Peter MacCallum Cancer Centre, St Andrews Place, East Melbourne, Australia 5 Division of Haematology and Medical Oncology, Peter MacCallum Cancer Centre, St Andrews Place, East Melbourne, Australia Accepted 22 December 2006 Published online 11 June 2007 in Wiley InterScience (www.interscience.wiley.com). DOI: 10.1002/hed.20629 Abstract: Background. The aim of this study was to deter- mine prospectively the incremental value of positron emission to- mography/computed tomography (PET/CT) over conventional assessment (clinical examination and CT/MRI imaging). Methods. All patients undergoing 18 F-fluorodeoxyglucose (FDG)-PET/CT for primary head and neck mucosal squamous cell carcinoma between January 2002 and December 2003 (in- clusive) were included in this study provided they had under- gone contemporaneous conventional assessment of the head and neck region and had 12 months minimum follow-up. Results. Seventy-six patients underwent 100 PET/CT scans. The majority of patients (74%) were treated with definitive (chemo)- radiotherapy. Median follow-up time was 28 months. PET/CT led to a TNM classification alteration in 34% (12/35), a change in radio- therapy planning technique and/or dose in 29% (10/35), and altered treatment response assessment in 43% (13/30). A complete metabolic response was predictive of overall survival (p ¼ .037). Conclusion. Our results support incorporation of PET/CT into the management paradigm of head and neck mucosal squa- mous cell carcinoma. V V C 2007 Wiley Periodicals, Inc. Head Neck 29: 986–995, 2007 Keywords: PET; CT-PET; head and neck; squamous cell carcinoma Positron emission tomography (PET) with the glucose analogue, 18 F-fluorodeoxyglucose (FDG), is a valuable tool with a rapidly expanding role in general oncology. 1–10 Our group and others have published on the utility of PET in head and neck mucosal squamous cell carcinoma (HNSCC). 11–18 FDG-PET is an excellent functional imaging modality but has inherent anatomical limitations. The development of single-unit PET/CT scanners has addressed this limitation. In general oncology, PET/CT has been shown to significantly reduce Correspondence to: C. Connell V V C 2007 Wiley Periodicals, Inc. 986 Utility of CT-PET in HNSCC HEAD & NECK—DOI 10.1002/hed November 2007