Accuracy of 3-T MRI for Preoperative T Staging of Esophageal Cancer After Neoadjuvant Chemotherapy, With Histopathologic Correlation

OBJECTIVE. The purpose of this study was to explore the value of 3-T MRI for evaluating the preoperative T staging of esophageal cancer (EC) treated with neoadjuvant chemotherapy (NAC), with histopathologic confirmation. SUBJECTS AND METHODS. This prospective study enrolled patients for whom endoscopic biopsy showed EC and pretreatment CT showed stage cT1N+ M0 or cT2-T4aN0-N3M0. All patients received two cycles of NAC (paclitaxel and nedaplatin protocol) followed by 3-T MRI and surgical resection. Readers assigned a T category on MRI, and postoperative pathologic confirmation was considered the reference standard. Interreader agreement, the diagnostic accuracy of T staging on T2-weighted turbo spin-echo (TSE) BLADE (Siemens Healthcare), contrast-enhanced StarVIBE (Siemens Healthcare), high-resolution delayed phase StarVIBE, and the combination of the three sequences were analyzed and compared with postoperative pathologic T staging. RESULTS. The study included 79 patients. Mean time between NAC and MRI was 23 days. Interreader agreements of T category assignment were excellent for T2-weighted TSE BLADE (kappa = 0.810, p < 0.0001), contrast-enhanced StarVIBE (kappa = 0.845, p < 0.0001), high-resolution delayed phase StarVIBE (kappa = 0.897, p < 0.0001), and the combination of the three sequences (kappa = 0.880, p < 0.0001). The highest accuracy for T0, T1, T2, and T4a lesions was on high-resolution delayed phase StarVIBE (96.2%, 92.4%, 91.1%, and 91.1% for reader 1; 94.9%, 89.9%, 91.1%, and 94.9% for reader 2), and the highest accuracy for T3 lesions was on T2-weighted TSE BLADE (92.4% and 94.9% for reader 1 and reader 2, respectively). Diagnostic accuracy of the combination of the three sequences was not improved compared with individual sequences. CONCLUSION. High-resolution delayed phase StarVIBE had the highest diagnostic accuracy in staging EC after NAC for all T categories except T3, for which T2-weighted TSE BLADE had the highest accuracy. Combining all three sequences did not improve diagnostic accuracy.