18FDG‐PET for the assessment of primary head and neck tumors: Clinical, computed tomography, and histopathological correlation in 38 patients

Abstract
Objectives: To evaluate the clinical usefulness of FDG‐PET (fluoro‐2‐deoxy‐glucose‐positron emission tomography) in the detection of lymph node involvement and recurrences in patients with head and neck cancer. Study Design: Retrospective review of 38 patients with biopsy‐proven head and neck cancers who underwent clinical, computed tomography (CT), and FDG‐PET examinations. Twenty‐five patients were studied prior to therapy and 13 patients were evaluated for disease recurrence. Methods: All patients were operated and clinical data, CT, and FDG‐PET results were correlated with histopathological findings. Results: All primary tumors in 25 patients were detected, with the exception of one small superficial localization of the epiglottis. Histopathological examination showed lymph node involvement in 10 patients; PET detected lymph node involvement in five. FDG‐PET found one case of nodal disease not identified by clinical and CT examination. With so few cases, this could be anecdotal. Five false‐negative results (microscopic lymph node involvement) and two false positives were noted. Twelve of 13 patients with recurrent disease were correctly identified with FDG‐PET. FDG‐PET was the only imaging technique to identify local recurrence in two patients and lymph node involvement in two others. One false‐positive result occurred in a patient with a foreign body granuloma. Conclusions: FDG‐PET is a useful diagnostic modality for the detection of recurrent tumors and, in selected cases, precise lymph node involvement. The best way to further investigate the utility of clinical FDG‐PET is in the follow‐up of treated patients. Key Words: FDG‐PET, head and neck cancer, lymph node metastases, recurrent disease. Laryngoscope, 108:1578–1583, 1998