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Could Some Rectal Cancer Patients Avoid Surgery?
CancerSnoop · Treatment News Explained
For some patients, treatment may offer a path without surgery.
New evidence is changing the conversation about a particular type
of rectal cancer. Understanding who qualifies is essential.
Could some rectal cancer patients avoid surgery?
Yes, selected patients have done so after immunotherapy.
But the evidence applies to a specific group, with careful assessment
and continued monitoring.
[Reference 1]
What Has Changed?
On October 19, 2026, the US FDA granted accelerated approval to
dostarlimab, sold as Jemperli, for adults with stage II or III locally
advanced rectal cancer that is MSI-H or dMMR, confirmed by an
FDA-authorized test.
[Reference 1]
Who This News Concerns
The tumour’s test results matter.
MSI-H and dMMR are laboratory classifications of the tumour.
Check the actual pathology report rather than assuming that every
rectal cancer belongs to this group.
What Did the Newer Trial Show?
AZUR-1 enrolled 154 previously untreated patients. At the reported
analysis, 110 patients—71%—had received dostarlimab alone, had needed
no additional treatment and had not experienced disease progression.
Twenty-six underwent surgery, with or without other treatment.
These figures are not lifetime cure rates.
[Reference 1]
What About the Study Where Every Patient Responded?
A separate phase 2 study, published in the
New England Journal of Medicine in 2025, included rectal
and other dMMR cancers.
All 49 rectal cancer patients who completed treatment achieved
a clinical complete response and chose nonoperative management.
Thirty-seven had a sustained clinical complete response at 12 months.
These are different outcomes and follow-up measures.
[Reference 2]
What the Study Supports
Organ preservation can be possible.
Selected patients avoided surgery after responding to treatment.
What It Does Not Establish
A response is not a lifetime guarantee.
The trial was not randomized, and follow-up varied.
It cannot prove that every eligible patient will remain
cancer-free permanently.
[Reference 2]
Does Avoiding Rectal Cancer Surgery Mean Doing Nothing?
No. Patients entering nonoperative management after a complete response
received active surveillance. In AZUR-1, this involved repeated
assessments every four months for two years, then every six months.
[Reference 1]
A Different Care Path
Avoiding an operation still involves a plan.
Ask who will coordinate follow-up, which tests will be used,
and what would trigger a change in treatment.
Is This an Option for Everyone?
ASCO’s 2024 guideline recommends immunotherapy for MSI-H or dMMR
locally advanced rectal cancer. It gives different treatment
recommendations for microsatellite-stable or mismatch
repair-proficient disease.
[Reference 3]
ASCO also discusses nonoperative management after a clinical complete
response to neoadjuvant treatment. The approach therefore depends on
both tumour characteristics and treatment response.
[Reference 3]
Keep the Populations Separate
A result in one group does not answer every treatment question.
This article concerns locally advanced, biomarker-selected rectal
cancer. Do not use these results alone to decide treatment for
colon cancer, metastatic disease or a tumour with different
laboratory findings.
What About Safety and Access?
FDA warnings include immune-mediated reactions and infusion reactions.
US approval does not itself establish approval or coverage elsewhere.
[Reference 1]
Treatment Decisions
Do not cancel planned care because of a headline.
Use the news to start a discussion with your treating team.
Bring your pathology results and ask how the evidence applies
to your situation.
Questions Worth Asking Your Team
- Has my tumour been tested for MSI and MMR?
- What do my results mean for treatment options?
- Does my diagnosis match the patients in these studies?
- How would you assess a complete response?
- What follow-up would I need without surgery?
- What is the plan if treatment does not work or cancer returns?
CancerSnoop Bottom Line
CancerSnoop Bottom Line
A meaningful new possibility, with important conditions.
The useful conversation starts with the individual diagnosis,
the tumour’s test results and the care plan.
Ask what this development could change for you—and what it cannot
yet promise.
Related CancerSnoop Articles
References and Trusted Sources
Reference 1 — FDA grants accelerated approval to dostarlimab
for locally advanced rectal cancer
U.S. Food and Drug Administration. October 19, 2026.
Reference 2 — Nonoperative Management of Mismatch Repair–Deficient Tumors
Cercek A, Foote MB, Rousseau B, et al.
New England Journal of Medicine.
2025;392:2297–2308. Published online April 27, 2025.
DOI: 10.1056/NEJMoa2404512 · PMID: 40293177
Reference 3 — Management of Locally Advanced Rectal Cancer:
ASCO Guideline
Scott AJ, Kennedy EB, Berlin J, et al.
Journal of Clinical Oncology.
2024;42:3355–3375. Published online August 8, 2024.
DOI: 10.1200/JCO.24.01160 · PMID: 39116386
Evidence and source check: October 27, 2026.
This article provides educational information and does not replace
individual advice from your cancer care team.
This article provides educational information and does not replace
individual advice from your cancer care team.
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