Value of orthogonal axial MR images in T-staging for gastric cancer: a retrospective comparison

Motivation: Orthogonal axial images (OAI), which may improve staging performance, had been ignored in previous studies about gastric cancer (GC) T-staging using MRI. Goal(s): To assess the value of MR OAI in GC preoperative T-staging. Approach: Diagnostic performance metrics, over- and understaging fractions, overall accuracy (compared by McNemar test) for MRI lacking or incorporating OAI and MDCT were quantified referring to pathological T-stage. Results: The overall accuracy was significantly higher for MRI with OAI than those without OAI, while marginally better than MDCT. Both MRI with OAI and MDCT exhibited superior staging performance than MRI without OAI. Impact: By incorporating orthogonal axis images, MRI exhibited diagnostic performance marginally better than MDCT in preoperative T-staging of gastric cancer, thereby offering a superior, non-invasive and radiation-free protocol to determine prognosis and guide appropriate treatment strategies.