Joonseok Lim MD, Presenter: Nothing to Disclose

Daehong Kim, Abstract Co-Author: Nothing to Disclose

Song-Ee Baek, Abstract Co-Author: Nothing to Disclose

The present study was conducted to monitor the permeability change of rectal cancer by chemoradiation and evaluate the utility of DCE-MR imaging based pharmacokinetic parameters as potential biomarkers for predicting response to chemoradiation therapy in locally advanced rectal cancer.

This prospective study was approved by an institutional review board; informed consent was obtained from all patients. Thirty-nine patients (mean age, 59.61 years; age range, 39 – 76 years; 27 men and 12 women) with primary rectal carcinoma who were undergoing preoperative CRT were recruited for the study. DCE-MR imaging was performed with a 3.0-T MR imager in all patients before therapy, at the end of 2nd week of therapy, and before surgery. Ktrans values were calculated. Repeated ANOVA test was applied to analyze the change in Ktrans values following treatment.

Accorindg to downstaging criteria on the basis of histopathologic examination, patients were assigned to the downstaged responder group( n = 20) or nondownstaged non-responder group ( n = 19). Before CRT, the mean tumor Ktrans values in the responder group was higher than that in the nonresponder group (1.93 ± 0.76/min vs. 1.35 ± 0.67/min, p=0.0178), but there was no significant difference between responder and non-responcer, divided by tumor regression grade (1.86 ± 0.67 vs. 1.49 ± 0.80, p=0.1392). The changes in Ktrans values at three time points (pre-CRT, 2 week, and post-CRT) were significantly different between the responder and non-responder for both criteria (p= 0.0215 and < 0.0001).  

Pretherapy higher Ktrans value of rectal cancer correlated with downstaged  responder to CRT. DCE-MR imaging is a promising noninvasive technique for helping predict and monitor therapeutic response in patients with rectal carcinoma who are undergoing CRT.

Pretherapy higher Ktrans value of rectal cancer correlate with good response to CRT. DCE-MR imaging is a promising noninvasive technique for helping predict and monitor therapeutic response.

Lim, J, Kim, D, Baek, S, MR Perfusion Imaging for the Prediction of Treatment Response after Preoperative Chemoradiotherapy in Locally Advanced Rectal Cancer.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11008866.html