Diffusion-weighted MR imaging using FASE sequence for 3T MR system: Preliminary comparison of capability for N-stage assessment by means of diffusion-weighted MR imaging using EPI sequence, STIR FASE imaging and FDG PET/CT for non-small cell lung cancer patients

Purpose To prospectively compare the diagnostic capability of diffusion-weighted MR imaging obtained with fast advantage spin-echo sequence (FASE-DWI) and echo planar imaging sequence (EPI-DWI), short inversion time inversion recovery fast advanced spin-echo (STIR FASE) imaging and FDG PET/CT for N-stage assessment of non-small cell carcinoma (NSCLC) patients. Materials and methods 95 consecutive operable NSCLC patients underwent STIR FASE imaging, FASE-DWI and EPI-DWI with a 3T system, integrated PET/CT, surgical treatment and pathological and follow-up examinations. Probability of lymph node metastasis was visually assessed using a 5-point visual scoring system. ROC analyses were used to compare diagnostic capability of all methods, while their diagnostic performance was also compared by means of McNemar's test on a per node basis. Finally, McNemar's test was also used for statistical comparison of accuracy of N-stage assessment. Results Areas under the curve (Azs) for STIR FASE imaging (Az = 0.95) and FASE-DWI (Az = 0.92) were significantly larger than those for EPI-DWI (Az = 0.78; p < 0.0001 for STIR FSE imaging and FASE-DWI) and PET/CT (Az = 0.85; p = 0.0001 for STIR FSE imaging, p = 0.03 for FASE-DWI) on a per node basis analysis. Accuracy of N-stage assessment using STIR FASE imaging (84.2% [80/95]) and FASE-DWI (83.2% [79/95]) was significantly higher than that using EPI-DWI (76.8% [73/95]; p = 0.02 for STIR FASE imaging, p = 0.03 for FASE-DWI) and PET/CT (73.7% [70/95]; p = 0.002 for STIR FSE imaging, p = 0.004 for FASE-DWI). Conclusion Qualitative N-stage assessments of NSCLC patients obtained with FASE-DWI as well as STIR FASE imaging are more sensitive and/or accurate than those obtained with EPI-DWI and FDG PET/CT.