Can dynamic MR imaging predict response in patients with rectal cancer undergoing cetuximab-based neoadjuvant chemoradiation?
BACKGROUND
The aim of this study was to evaluate therapy response in patients undergoing cetuximab-CapIri-based chemoradiation for rectal cancer using dynamic magnetic resonance imaging (dMRI).


METHODS
The volumetric degree of tumor regression and contrast media perfusion were compared to the results of the histopathologic ypTN staging. 33 patients were examined using a 1.5-T scanner with repetitive 2D FLASH sequences after contrast media application. All patients were examined twice - before therapy and immediately before surgery.


RESULTS
In all patients, the tumor volume decreased (mean 72 +/- 16%). In 25/33 patients, the slope of the contrast media enhancement curve decreased (mean 31 +/- 20%). In histopathologically proven downstaging after therapy, the decrease in slope was significantly higher than in the group without downstaging, and the decrease in slope was better for distinguishing between 'responder' and 'non-responder' than the decrease in volume.


CONCLUSIONS
Using dMRI helps to identify responders undergoing cetuximab-based chemoradiation better than volume decrease alone.
Dinter
Dietmar J
DJ
Institut für Klinische Radiologie und Nuklearmedizin, Medizinische Fakultät Mannheim der Universität Heidelberg, Heidelberg, Germany. dietmar.dinter@medma.uni-heidelberg.de
Horisberger
Karoline
K
Zechmann
Christian
C
Wenz
Frederik
F
Brade
Joachim
J
Willeke
Frank
F
Neff
K Wolfgang
KW
Schoenberg
Stefan O
SO
Hofheinz
Ralf-Dieter
RD
D000328:Adult; D000368:Aged; D000911:Antibodies, Monoclonal / Q000008:administration & dosage*; D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents / Q000008:administration & dosage; D000068818:Cetuximab; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D018714:Radiotherapy, Adjuvant / Q000379:methods; D020266:Radiotherapy, Conformal; D012004:Rectal Neoplasms / Q000175:diagnosis* / Q000628:therapy*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016896:Treatment Outcome
D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents; D000068818:Cetuximab