“Comparative diagnostic accuracy of dual-energy CT, diffusion-weighted MRI and chemical shift MRI in cervical lymph node metastasis in head and neck cancer”
Rajesh Kanna S, Lokesh Rana, Narvir Singh Chauhan, Sudesh Kumar, Manupriya Sharma, Armaan GuptaAbstract
Objectives
To compare the diagnostic performance of Dual-Energy CT (DECT), Diffusion-Weighted MRI (DWI), and Chemical Shift MRI (CSI) in differentiating metastatic from non-metastatic cervical lymph nodes in patients with head and neck cancer, using histopathology as the reference standard.
Methods
In this prospective cross-sectional study, 38 patients with suspected head and neck malignancy underwent DECT, DWI, and CSI prior to histopathological evaluation. A total of 194 lymph nodes were analysed. Quantitative parameters including DWI- apparent diffusion coefficient (ADC), DECT- normalised iodine concentration (NIC), spectral HU, electron density, effective atomic number and CSI in–out phase ratio were assessed. Diagnostic performance was evaluated using receiver operating characteristic (ROC) analysis, and comparison between modalities was performed using the DeLong test.
Results
Of 194 lymph nodes, 71 were metastatic and 122 were non-metastatic. ADC values were significantly lower in metastatic nodes (p < 0.0001). Dual-energy CT parameters and chemical shift MRI did not show statistically significant differences. ROC analysis demonstrated superior diagnostic performance of ADC compared to other parameters.
Conclusion
DWI demonstrates superior diagnostic performance in differentiating metastatic cervical lymph nodes, while DECT and CSI show limited utility. Multiparametric MRI, particularly DWI, should be preferred for nodal characterization in head and neck cancer.
Advances in knowledge
This study provides direct comparative evidence showing that ADC-based DWI is significantly superior to DECT quantitative parameters and CSI for nodal metastasis detection, supporting its role as the primary functional imaging tool.