Clinical Significance of Postradiotherapy [18F]-Fluorodeoxyglucose Positron Emission Tomography Imaging in Management of Head-and-Neck Cancer—A Long-Term Outcome Report
Received 16 June 2008; received in revised form 16 July 2008; accepted 20 July 2008. published online 20 October 2008.
Purpose
To determine the accuracy and prognostic significance of post-treatment [18F]-fluorodeoxyglucose positron emission tomography (FDG-PET) in head-and-neck squamous cell carcinoma after radiotherapy (RT).
Methods and Materials
This was a retrospective study of 188 patients with head-and-neck squamous cell carcinoma who had undergone FDG-PET within 12 months after completing RT. All living patients had ≥1 year of follow-up after FDG-PET. All patients had undergone intensity-modulated RT, 128 with definitive and 60 with postoperative intensity-modulated RT.
Results
For all patients, the median follow-up after RT completion was 32.6 months and after FDG-PET was 29.2 months. For the neck, 171 patients had negative FDG-PET findings. Of these results, two were falsely negative. Seventeen patients had positive FDG-PET findings, of which 12 were true-positive findings. The sensitivity, specificity, positive predictive value, and negative predictive value for FDG-PET in the assessment of the treatment response in the neck was 86%, 97%, 71%, and 99%, respectively. For the primary site, 151 patients had negative FDG-PET findings, of which two were falsely negative. Thirty-seven patients had positive FDG-PET findings, of which 12 were true-positive findings. The sensitivity, specificity, positive predictive value, and negative predictive value for FDG-PET in the assessment of the treatment response in the primary site was 86%, 86%, 32.4%, and 98.7%, respectively. Patients with positive post-RT PET findings had significantly worse 3-year overall survival and disease-free survival.
Conclusion
The results of our study have shown that the findings of post-RT FDG-PET have a high negative predictive value and are a significant prognostic factor. It can provide guidance for the management of head-and-neck cancer after definitive treatment.
∗Department of Radiation Oncology, University Hospitals Case Medical Center, Cleveland, OH
†Department of Otolaryngology-Head and Neck Surgery, University of Nebraska Medical Center, Omaha, NE
‡Department of Otolaryngology-Head and Neck Surgery, University of Iowa, Iowa City, IA
¶Department of Radiology, University of Iowa, Iowa City, IA
‖Department of Radiation Oncology, University of Iowa, Iowa City, IA
§University of Nevada at Reno School of Public Health, Reno, NV
Reprint requests to: Min Yao, M.D., Ph.D., Department of Radiation Oncology, University Hospitals, Case Medical Center, 11100 Euclid Ave., Cleveland, OH 44106. Tel: (216) 844-2537; Fax: (216) 844-2005
Presented, in part, at the 49th Annual Meeting of the American Society for Therapeutic Radiology and Oncology, Los Angeles, CA, October 28 to November 1, 2007.
ABSTRACT