RESUMO
BACKGROUND: The purpose of this study was for us to review diagnostic accuracy of diffusion-weighted imaging (DWI) in primary head and neck squamous cell carcinomas (HNSCCs), detection of metastatic lymph nodes, and recurrences. METHODS: A systematic review for studies concerning DWI was performed. RESULTS: Ten studies fulfilled inclusion criteria. All studies showed significant higher "apparent diffusion coefficient" (ADC) in benign compared to malignant lesions. ADC thresholds for optimal discrimination varied. In detection of primary HNSCC, the accuracy of DWI ranged from 66% to 86%. In metastatic lymph nodes, the accuracy of DWI was 85% to 91% and the negative predictive value (NPV) was higher than 91%. For recurrences, the accuracy of DWI was 78% to 100% and the NPV ranged from 77% to 100%. CONCLUSION: DWI showed consistent high accuracy and high NPV. However, available literature is sparse and varying ADC thresholds were reported. Compared to current imaging techniques, DWI showed the most potential in lymph node staging and detection of recurrences.