How Can We Identify Pathologic Complete Responders After Chemoradiotherapy?

  • Doenja M. J. Lambregts
  • Regina G. H. Beets-Tan


With the introduction of organ-preserving treatment strategies, response evaluation after chemoradiotherapy is becoming an increasingly relevant issue. When accurately selected, patients with a complete tumour response may be offered a ‘watch-and-wait’ approach instead of surgical resection. Imaging plays an important role in assessing response after chemoradiotherapy. However, for the identification of complete responders, MRI as well as endorectal ultrasound and CT show limited accuracy, mainly due to difficulties in discriminating viable tumour remnants within post-radiation fibrosis. Addition of diffusion-weighted imaging can significantly improve the performance of MRI in identifying complete responders. Best results are obtained when combining MRI (including diffusion MRI) with digital rectal examination and endoscopy.



Apparent diffusion coefficient




Computed tomography


Dynamic contrast enhanced


Digital rectal examination


Diffusion-weighted (magnetic resonance) imaging


Endorectal (or endoscopic) ultrasound


Magnetic resonance imaging


Positron emission tomography/18F-fluorodeoxygenase positron emission tomography


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Copyright information

© Springer-Verlag Berlin Heidelberg 2018

Authors and Affiliations

  • Doenja M. J. Lambregts
    • 1
  • Regina G. H. Beets-Tan
    • 1
  1. 1.Department of RadiologyThe Netherlands Cancer InstituteAmsterdamThe Netherlands

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