FDG-PET prediction of head and neck squamous cell cancer outcomes

Objective: To confirm that high pretreatment uptake of 2-deoxy-2[ ¹⁸F]fluoro-D-glucose (FDG) detected by positron emission tomography (PET) measured at the primary head and neck squamous cell carcinoma (HNSCC) and at metastatic nodal disease predicts poor outcomes for HNSCC. Design and Patients: We enrolled 63 consecutive patients with a histological diagnosis of HNSCC (including tumors of the oral cavity, oropharynx, larynx, and hypopharynx) from September 2000 through June 2003, into a prospective institutional imaging trial. Fifty-four patients (86%) underwent a baseline FDG-PET scan before curative treatment and were eligible for analysis. Results: A primary tumor standardized uptake value (SUV) of greater than 9.0 predicted inferior local recurrence-free survival (P=.02) and disease-free survival (P=.03). Nodal SUV dichotomized according to the cohort median of 6.1 did not predict for either disease outcome (P= .71 and P= .98, respectively). On proportional hazards analysis, local recurrence and disease event hazard ratios for a primary tumor SUV of 9.0 or greater remained significant or at borderline significance when adjusted for nodal SUV or other clinical covariates. Conclusions: Our findings support an association between baseline primary tumor FDG SUV and HNSCC outcomes. In contrast, nodal FDG SUV was not predictive. Primary tumor FDG SUV is a promising prognostic factor and may establish the need for intensified locoregional therapy in individual patients. Multiinstitutional imaging trials and further characterization of the biology responsible for elevated FDG uptake in HNSCC will be necessary to confirm the prognostic utility of FDG-labeled PET.