The FDA has approved an immunotherapy that could spare some rectal cancer patients chemotherapy, radiation and major surgery. But only a small group qualifies, and doctors are still studying how long the benefits last.
A rectal cancer diagnosis can turn a family’s life upside down. Beyond the fear of cancer itself, patients may face months of chemotherapy, radiation and surgery that can permanently change how their bodies function.
Some worry about needing a colostomy bag. Others face the possibility of losing their fertility or living with long-term bowel problems.
Now, a newly approved treatment could offer certain patients a different path.
On October 19, the Food and Drug Administration approved Jemperli (dostarlimab), an immunotherapy that helps the body’s immune system fight cancer.
In a clinical trial involving 154 patients, 110, or 71%, received the drug without needing surgery, chemotherapy or radiation afterward. They also had no reported cancer progression at the study’s assessment.
It’s a promising result. But it doesn’t mean the treatment works for everyone, or that those patients are cured.
The approval is specifically for adults with previously untreated stage II or III rectal cancer whose tumors have certain genetic characteristics.
Doctors call them MSI-H and dMMR. Both involve problems with how cancer cells repair damage to their DNA, making them more vulnerable to this type of immunotherapy.
According to the FDA, only about 3% of locally advanced rectal cancers have these characteristics.
That makes tumor testing especially important. Someone diagnosed with rectal cancer cannot assume this treatment is an option simply because it has received FDA approval.
For patients and families, the first question is straightforward: Has my tumor been tested for MSI-H or dMMR?
What happened to patients in the study?
The FDA based its approval primarily on a clinical trial called AZUR-1.
Patients received dostarlimab through an IV every three weeks, for up to nine treatments over approximately six months.
The FDA’s detailed review of the results found:
- 110 of 154 patients (71%) needed no additional cancer treatment and had no reported disease progression.
- 26 patients (17%) underwent surgery, with or without other treatments.
- 13 patients (8%) received additional chemotherapy or radiation without surgery.
Five others experienced progression without further treatment, withdrew or were lost to follow-up.
Researchers also measured something different: whether patients maintained a complete clinical response, meaning examinations found no detectable cancer.
Independent reviewers confirmed a sustained response lasting 12 months in 47% of 116 evaluable patients. The treating investigators reported a higher rate of 68% using their own assessments.
Those figures are not interchangeable, and none represents a universal cure rate.
Rectal cancer treatment can save lives. But for some patients, life afterward looks very different.
Surgery may affect bowel control or require a permanent colostomy. Chemotherapy and radiation can also affect fertility, sexual health and urinary function.
These changes can reach into everyday life, from returning to work to caring for children or simply feeling comfortable outside the house.
For California’s Latino families, access to cancer care is already an important concern. As Parriva previously reported, colorectal cancer is rising among younger adults, with particularly rapid increases among Latinos.
That doesn’t mean Latino patients are more likely to qualify for this immunotherapy. Eligibility depends on the tumor, not ethnicity.
But it makes access to testing, specialists and timely treatment an important part of the conversation.
Does avoiding surgery mean the cancer is cured?
Not necessarily.
The AZUR-1 study followed patients for a median of 26.3 months. Researchers still need more time to learn how often cancer returns and whether patients continue doing well without conventional treatment.
The study also did not directly compare patients randomly assigned to immunotherapy versus standard treatment.
The FDA granted accelerated approval, allowing the drug to become available while additional evidence is collected.
An earlier study of 50 patients showed encouraging results, although one of 27 patients followed for at least three years experienced a local recurrence.
The treatment also carries risks. Common side effects include fatigue, rash, diarrhea and itching. Serious immune reactions can damage healthy organs and, in rare cases, be fatal.
Even patients whose cancer becomes undetectable need regular examinations and scans.
What patients should ask their doctors
For someone facing a rectal cancer diagnosis, these questions can help start a conversation:
- Has my tumor been tested for MSI-H or dMMR?
- Could this immunotherapy be an option before surgery?
- What are the risks, and how will doctors know whether it’s working?
- What follow-up care will I need if my cancer becomes undetectable?
- Will my insurance cover the drug, testing and monitoring?
Coverage and out-of-pocket costs may vary. Families concerned about medical bills can also review our reporting on hospital financial assistance in Los Angeles County.
The FDA approval opens a new possibility for a small group of patients who once faced a much more difficult treatment path.
For those who qualify, the hope is real. So is the need for careful testing, medical guidance and long-term follow-up.
