FDG PET evaluation of head and neck cancer: Value of imaging the thorax

Background: Patients with primary tumors of the head and neck have been rep orted to have a high rate of synchronous primary tumors of the upper aerodi gestive tract. This study was performed to determine whether inclusion of t he thorax in the scan volume would be diagnostically useful for positron em ission tomography (PET) with [F-18] fluorodeoxy-D-glucose (FDG) in patients with primary tumors of the head and neck. Methods. FDG PET scans from the midcranium to the diaphragm were obtained o n 56 patients with a variety of head and neck tumors on initial examination before definitive therapy. PET findings in the chest were correlated with results of all other imaging studies, biopsy results, and clinical follow-u p. Results. In nine studies (16%), areas of increased FDG uptake in the chest were seen and were judged to be tumors. Six of these probably were false-po sitive results, although one of these six may have been unconfirmed true po sitives. Of the three confirmed true-positive studies, two were obvious fro m other routine studies. In only one case did the PET study reveal a signif icant lesion not found by means of routine evaluation, resulting in a case- finding yield of 2%. If the unconfirmed possible true-positive results are included, the case-finding yield increases to 4%. Conclusions. No compelling indication was seen for including the chest in P ET studies of patients with head and neck cancer. (C) 2000 John Wiley & Son s, Inc.