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CC BY 4.0 · Journal of Gastrointestinal and Abdominal Radiology
DOI: 10.1055/s-0045-1802595
Review Article

Response Assessment after Neoadjuvant Chemoradiotherapy in Rectal Cancer

Anuradha Chandramohan 
1   Abdominal Imaging Unit, Department of Radiology, Christian Medical College Vellore, Tamil Nadu, India
,
Antony Augustine
2   Department of Radiology, Luton and Dunstable University Hospital, Luton, United Kingdom
,
Sneha Hiriyanna
1   Abdominal Imaging Unit, Department of Radiology, Christian Medical College Vellore, Tamil Nadu, India
,
Shobiga Natarajan
1   Abdominal Imaging Unit, Department of Radiology, Christian Medical College Vellore, Tamil Nadu, India
,
Ajeet A. Selvam
1   Abdominal Imaging Unit, Department of Radiology, Christian Medical College Vellore, Tamil Nadu, India
,
Kurian C. Eapen
1   Abdominal Imaging Unit, Department of Radiology, Christian Medical College Vellore, Tamil Nadu, India
,
Saloni A. Yadav
1   Abdominal Imaging Unit, Department of Radiology, Christian Medical College Vellore, Tamil Nadu, India
,
Joseph Chacko Paul
1   Abdominal Imaging Unit, Department of Radiology, Christian Medical College Vellore, Tamil Nadu, India
,
Aisha Lakhani
1   Abdominal Imaging Unit, Department of Radiology, Christian Medical College Vellore, Tamil Nadu, India
,
Betty Simon
1   Abdominal Imaging Unit, Department of Radiology, Christian Medical College Vellore, Tamil Nadu, India
,
Anu Eapen
1   Abdominal Imaging Unit, Department of Radiology, Christian Medical College Vellore, Tamil Nadu, India
› Author Affiliations Funding The authors declare that this work did not receive financial support or funding.
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Abstract

Management of locally advanced rectal cancer is complex, and magnetic resonance imaging (MRI) findings play a central role in treatment decisions. While neoadjuvant chemoradiotherapy significantly improved local recurrence rates, newer treatment modalities, such as total neoadjuvant chemotherapy, improved distant control. They significantly improved pathological complete response rates, enabling organ preservation in more patients. MRI is the best imaging modality to assess treatment response. MRI aids in assessing operability, predicts surgical outcomes following neoadjuvant treatment, and aids in identifying patients' eligible for organ preservation and their follow-up. In this review, we discuss imaging techniques and interpretation of rectal cancer MRI following neoadjuvant treatment, provide a structured reporting template for response assessment MRI, and detail how imaging findings influence treatment decisions.

Keywords

MRI - rectal cancer - MDT - restaging - neoadjuvant chemoradiotherapy

Ethical Approval and Consent to Participate

Not applicable.


Authors' Contributions

All authors contributed to the concept/design, a draft of the manuscript, and its editing. All authors read and approved the final manuscript. A.C. is the guarantor for the contents of the manuscript.




Publication History

Article published online:
14 February 2025

© 2025. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution License, permitting unrestricted use, distribution, and reproduction so long as the original work is properly cited. (https://creativecommons.org/licenses/by/4.0/)

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