CLINICAL UTILITY OF POSITRON-EMISSION-TOMOGRAPHY WITH F-18 FLUORODEOXYGLUCOSE IN DETECTING RESIDUAL RECURRENT SQUAMOUS-CELL CARCINOMA OF THE HEAD AND NECK/

PURPOSE: The use of positron emission tomography with F-18-fluorodeoxy glucose (FDG-PET) to detect residual/recurrent squamous cell carcinoma of the head and neck has been tested only in small groups of patients . Our purpose, therefore, was to evaluate the ability of this techniqu e to detect the presence of tumor at both primary and nodal sites in a large cohort of patients. METHODS: All patients referred for PET scan ning over a 2.5-year period with a question of residual or recurrent s quamous cell carcinoma of the head and neck were identified, Thirty-fi ve of 44 patients had sufficient follow-up to be meaningful to our ana lysis (range, 6-33 months), PET scans were interpreted visually with k nowledge of the clinical history and correlative anatomic imaging find ings. Detection of disease involving primary and nodal sites was asses sed independently. Additionally, because each patient had been referre d in an attempt to resolve a specific clinical problem, the usefulness of PET in accurately addressing these questions was assessed. RESULTS : At the primary site, sensitivity and specificity for residual/recurr ent disease were 100% and 64%, respectively; for nodal disease, sensit ivity and specificity were 93% and 77%, respectively, In helping to re solve the clinical question being asked, the positive predictive value of the test result was 65% and the negative predictive value was 91%, CONCLUSION: The high sensitivity and negative predictive value of PET scanning in our cohort of patients suggest an important role for this technique in the care of patients with suspected residual/recurrent h ead and neck carcinoma, The lower figures obtained for specificity and positive predictive value reflect the fact that increased FDG uptake may be due to either tumor or inflammation.