Pretreatment evaluation of distant-site status in patients with nasopharyngeal carcinoma: accuracy of whole-body MRI at 3-Tesla and FDG-PET-CT

We sought to prospectively evaluate the accuracy of 3.0-Tesla whole-body magnetic resonance imaging (WB-MRI) and integrated fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) (FDG-PET-CT), and their combined interpretation for the assessment of distant-site status in 150 patients with untreated nasopharyngeal carcinoma (NPC). Eighteen (12%) patients were diagnosed as having distant malignancies (15 patients had distant metastases, and three distant synchronous tumours). On a patient-based analysis, WB-MRI and FDG-PET-CT showed similar sensitivity (77.8% vs 72.2%, P > 0.999), specificity (98.5% vs 97.7%, P > 0.999) and diagnostic capability (0.905 vs 0.878, P = 0.669). Combined interpretation of WB-MRI and FDG-PET-CT showed no significant benefit over either technique alone. In conclusion, 3.0-Tesla WB-MRI is a feasible, non-ionising technique that showed similar diagnostic capacity to FDG-PET-CT in assessing distant-site status in patients with untreated NPC and can be recommended as the first-line imaging technique for comprehensive evaluation of such patients.