Comparison of the sensitivity and specificity of CT and MR imaging in the detection of cervical nodal tumor necrosis and extracapsular tumor spread

This paper evaluates if MR imaging can achieve the sensitivity and specificity of enhanced CT in detecting tumoral nodal necrosis (TNN) and extracapsular tumor spread (ETS). Enhanced CT scans and unenhanced and enhanced MR images were retrospectively and separately reviewed by a study-blinded radiologist. Fifty-eight lymph nodes were evaluated for TNN and ETS. Readings were given for CT, T1-weighted MR, T2-weighted MR, T1-weighted and T2-weighted MR, enhanced T1-weighted fat-suppressed MR, and T1-weighted, T2-weighted, and enhanced fat suppressed T1-weighted MR. Pathology proof was used to assess TNN; CT and used to assess ETS. Enhanced CT had the highest sensitivity for TNN. The sensitivity of unenhanced MR ranged from 33% to 50%; that of enhanced MR was 47%. All MR sequences and cT had specificities for TNN >92%. The highest accuracy of MR for TNN was the unenhanced T1-weighted and T2-weighted images alone; CT accuracy was 90%. MR sensitivity for ETS was maximal with T1-weighted images; all sequences had specificities >90%. Gadolinium-enhanced images did not improve accuracy in TNN or ETS