Detection of cervical metastases with 11C-tyrosine pet in patients with squamous cell carcinoma of the oral cavity or oropharynx: A comparison with 18F-FDG PET

Abstract

Background. A disadvantage of 2-[18F]fluoro-2-deoxy-D-glucose (18F-FDG) positron emission tomography (PET) in head and neck cancer is that 18F-FDG uptake is not specific to malignant tissue. To provide an alternative, radiolabeled amino acids such as L-1-[ 11C]-tyrosine (11C-TYR), were introduced because these are less avidly metabolized by inflammatory cells. Methods. In this prospective study, we compared both 11C-TYR PET and 18F-FDG PET performance in detecting cervical metastases in 27 patients with a squamous cell carcinoma (SCC) of oral cavity or oropharynx. Results. 11C-TYR PET sensitivity, specificity, and accuracy for detecting nodal metastases were 33%, 100%, and 81%, respectively. With respect to 18F-FDG PET, these figures were 67%, 97%, and 89%, respectively. Neck metastases not detected by 11C-TYR PET were camouflaged by high tracer uptake by salivary glands. Conclusions. Because of bilateral accumulation of 11C-TYR in salivary glands, 11C-TYR PET is not suitable to replace 18F-FDG PET in staging SCC of oral cavity and oropharynx. © 2009 Wiley Periodicals, Inc.