The Role of Functional MRI in The Evaluation of The Treated Head and Neck Squamous Cell Carcinoma

Background: The diffusion-weighted imaging (DWI) with apparent diffusion coefficient (ADC) map and the dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) constitute the functional MRI technique with many oncological applications as it can define tissue microstructure and characterize the post-treatment changes from a recurrent tumor in treated head and neck squamous cell carcinoma (HNSCC). Objective: To evaluate the role of the DWI, ADC map and DCE-MRI for characterization of post-treatment changes and recurrent tumors in patients with treated HNSCC. Patients and Methods: Forty-five patients with treated HNSCC were included in this study with mean ages of 59 ± 7.5 years. The patients underwent pre and post-contrast head and neck MRI, DWI with ADC map and DCE-MRI, each study diagnosis was then compared to the patient outcome. Results: The sensitivity and specificity of the qualitative DWI (DW-MRI) (87.5% and 82.8% respectively) were higher than the conventional MRI (75% and 75.9% respectively). The ADC cut-off point for the diagnosis of HNSCC recurrence was 1.095 x10-3 mm2/s with sensitivity and specificity of 87.5%, 86.2% respectively. The DCE- MRI revealed a significant difference in the type of time intensity curve (TIC) between post-treatment changes and recurrent lesion (p-value < 0.0001). Conclusion: The DWI, ADC and the DCE-MRI can be used as a synchronized tool for the differentiation between post-treatment changes and recurrent tumor in treated HNSCC patients.