The purpose of this study was to assess the diagnostic performance of FDG PET or PET/CT for detection of local, regional, and distant recurrences in the follow-up of patients with head and neck cancer who underwent definitive treatment.

A systematic search was performed in MEDLINE and Cochrane Library (updated September 2014) to identify relevant published studies. Studies investigating the accuracy of FDG PET/CT that were performed at least 4 months after therapy were included. Two authors independently screened all retrieved articles, selected studies that met the inclusion criteria, and extracted the data. Histopathologic confirmation or clinical follow-up of at least 6 month (or both) was considered as the reference standard.

Twenty-three studies constituting a total of 2247 FDG PET/CT examinations met our inclusion criteria. The pooled sensitivity and specificity of follow-up PET/CT for detection of recurrence were 0.92 (95% CI, 0.90-0.94), and 0.87 (95% CI, 0.82-0.91), respectively. The pooled sensitivity and specificity of scans performed 4-12 months after treatment were 0.95 (95% CI, 0.91-0.97) and 0.78 (95% CI, 0.70-0.84), respectively. Similar estimates for scans performed at or more than 12 months after treatment were 0.92 (95% CI, 0.85-0.96) and 0.91 (95% CI, 0.78-0.96), respectively. The overall accuracy of FDG PET/CT in detecting recurrence is higher in patients without suspicion of recurrence before the scan compared with the patients with suspected recurrence.

The high diagnostic performance of FDG PET/CT in detecting recurrence in curatively treated patients with head and neck cancer supports its use in clinical practice for patient follow-up. Further studies are needed to evaluate the prognostic utility of PET/CT in the follow-up of head and neck cancer.