MRI has emerged as a valuable tool for optimising treatment pathways in rectal cancer patients following neoadjuvant chemoradiation.
Recent findings from the OPRA (Organ Preservation in Rectal Adenocarcinoma) trial suggest that advanced MRI techniques can effectively stratify patients by risk, offering guidance on whether surgery can be deferred in favour of a non-operative ‘watch-and-wait’ approach.
Arun Krishnaraj and colleagues analysed MRI’s predictive capabilities for rectal cancer outcomes, including disease recurrence, progression, and survival.
The study evaluated 277 patients with locally advanced rectal cancer (LARC) who underwent MRI staging following neoadjuvant therapy. The mean follow-up was four years.
Their results demonstrated that MRI reliably predicts:
• Residual disease status following neoadjuvant therapy.
• Risk of local recurrence and distant metastasis.
• Bowel preservation outcomes, assisting in surgical decision-making.
MRI provides surgeons and oncologists with critical information to individualise care. Specifically:
Patients demonstrating a complete clinical response (cCR) on MRI may be suitable candidates for a nonoperative watch-and-wait protocol, avoiding the morbidity of total mesorectal excision (TME).
MRI findings can stratify recurrence risk, enabling tailored surveillance regimens for patients opting for nonoperative management.
Combining MRI with post-treatment endoscopic assessment may improve predictive accuracy, enhancing confidence in treatment pathways.
Dr Krishnaraj, director of UVA Health’s Division of Body Imaging, said: ‘No one wants to undergo surgery unnecessarily. With advanced MRI techniques, we can better identify which patients will benefit most from surgery and which can safely pursue organ preservation.’
TME remains the gold standard for managing rectal cancer with residual disease after chemoradiation. While this approach is often curative, it is associated with significant long-term sequelae, including permanent colostomy, urinary dysfunction, and impaired sexual function.
As colorectal cancer incidence rises in younger patients, balancing oncologic control with quality-of-life considerations is increasingly critical.
The OPRA trial’s data suggest that MRI can be a ‘crystal ball’ for predicting cCR and future disease progression.
With continued advancements, the integration of MRI and endoscopic evaluation may approach near-perfect predictive accuracy, as highlighted by the authors.
The researchers advocate for further studies to refine MRI protocols and validate their findings in larger cohorts. Combining radiologic and clinical markers holds promise for improving patient selection and achieving optimal oncologic and functional outcomes.
The study is published in Radiology.
