Abbreviations: AUC = area under the curve, CRT = chemoradiation therapy, mrTRG = magnetic resonance tumor regression grade, NPV = negative predictive value, PPV = positive predictive value, ypT = yield pathologic T.
This study was supported by a faculty research grant of Yonsei University College of Medicine (4-2011-0445).
The authors have no conflicts of interest to disclose.