18F-FDG PET/CT surveillance at 3-6 and 12 months for detection of recurrence and second primary cancer in patients with head and neck squamous cell carcinoma

Background: Early detection of recurrence of head and neck squamous cell carcinoma (HNSCC), which is often obscured by surgical or radiotherapy-induced tissue distortion, is essential for proper patient management. Methods: A total of 143 consecutive patients with previously untreated HNSCC were evaluated by whole-body fluorine 18-fluorodeoxyglucose positron emission tomography/computed tomography (F-18-FDG PET/CT) and regular clinical follow-up after curative treatment. The F-18-FDG PET/CT was performed similar to 3-6 and 12 months after treatment and findings suspicious for recurrence or SPC were confirmed using histopathology. Results: The sensitivities of 3-6- and 12-month PET/CT scans at patient level were 96% and 93%, respectively, and those of regular clinical follow-up were 11% and 19%, respectively (McNemar test, P<0.001). In patients with no clinical suspicion, PET/CT detected 95% and 91% of recurrent patients at 3-6 and 12 months, respectively. The sensitivity of PET/CT for the identification of SPC was 29% and 80% at 3-6 and 12 months, respectively. A positive interpretation of PET/CT was significantly associated with poor overall survival (log-rank test, P<0.001). Conclusion: The F-18-FDG PET/CT surveillance is beneficial for the detection of recurrence that may be missed by regular follow-up physical and endoscopic examinations of the head and neck area after curative treatment for HNSCC.