Chest radiography or chest CT plus head and neck CT versus 18F-FDG PET/CT for detection of distant metastasis and synchronous cancer in patients with head and neck cancer

Objectives Current guidelines recommend chest computed tomography (CT) with locoregional CT/magnetic resonance imaging for patients with head and neck squamous cell carcinoma (HNSCC), and 18F-fluorodeoxyglucose (FDG) positron-emission tomography (PET)/CT is suggested for stage III–IV patients. However, whole body screening with 18F-FDG PET/CT may provide better detection of distant metastases and synchronous cancer than conventional imaging. We evaluated the utility of 18F-FDG PET/CT in detecting distant metastasis and synchronous cancer. Methods This prospective study enrolled 740 consecutive patients with previously untreated HNSCC diagnosed between September 2010 and December 2015. Synchronous cancer was histologically confirmed and distant metastases were confirmed by biopsy or serial imaging follow-ups. McNemar test was used to compare the true-positive detection rates of chest radiography (CXR) + head and neck CT (hnCT) (A) versus 18F-FDG PET/CT (C) and chest CT + hnCT (B) versus 18F-FDG PET/CT. Results Distant metastases and synchronous cancer were found in 23 (3.1%) and 55 (7.4%) patients, respectively. A, B, and C detected distant metastases in 10 (1.3%), 19 (2.6%), and 21 (2.8%) patients, respectively. The absolute differences were 1.5% (A versus C, P = 0.003) and 0.3% (B versus C, P = 0.687). A, B, and C detected synchronous cancer in 15 (2.0%), 22 (2.9%), and 36 (4.9%) patients, respectively. The absolute differences were 2.8% (A versus C, P Conclusions 18F-FDG PET/CT detected more distant metastases and synchronous cancer than CXR + hnCT and more synchronous cancer than chest CT + hnCT.