Usefulness of fluorine-18 fluorodeoxyglucose positron emission tomography in patients with a residual structural abnormality after definitive treatment for squamous cell carcinoma of the head and neck.

BACKGROUND: Residual structural abnormalities after definitive treatment of head and neck squamous cell carcinoma (HNSCC) are common and pose difficult management problems. The usefulness of fluorine-18 fluorodeoxyglucose positron emission tomography (FDG PET) to supplement conventional evaluation with clinical and standard radiologic examination (CE) in such patients was assessed.

METHODS: Fifty-three eligible patients were identified with residual structural abnormalities on CE. True disease extent could be validated in 46 patients. Patients had a median potential follow-up of 55 months (range, 41-75 months) from the date of PET scan to the analysis closeout date.

RESULTS: PET had better diagnostic accuracy than CE (p = .0002) and induced management change in 21 patients (40%; 95% confidence interval [CI], 26%-54%), including avoidance of unnecessary planned surgery in 14 patients with negative PET. Appropriate management change was confirmed in 19 (95%) of 20 evaluable cases. Disease presence and extent assessment by PET were significant predictors of survival (p < .0001), whereas the extent of disease determined by CE was not.

CONCLUSION: PET added significantly to the value of CE in restaging disease in patients with structural abnormalities after definitive treatment of HNSCC. Management decisions based on PET were appropriate in most patients.