Why more cancer patients are turning to molecular residual disease testing for answers

It’s often said that knowledge is power. Power to calm the mind. Power to make informed choices. And for Kristi, a breast cancer survivor, knowledge gave her the power of a positive mindset, one that’s been nothing short of life-changing.

She gained this knowledge by way of the Oncodetect^® test, a molecular residual disease (MRD) test developed by Exact Sciences. In 2024, Kristi was diagnosed with triple-negative breast cancer, one of the most aggressive forms of the disease.¹ She underwent two surgeries, six rounds of chemotherapy, and 20 sessions of radiation. She trusted her care team. She trusted the process. But on the other side of treatment, she found herself gripped by a thought familiar to so many survivors: How will I know if it’s really gone?

“That was probably half of my headspace at the time, worrying about what if this comes back?” said Kristi.

Kristi’s close friend and advocate, Diane, helped her find the answer. Diane, a breast cancer survivor herself, knew first-hand what genomic testing could do. Hers was a different type of breast cancer, one that made her eligible for a separate Exact Sciences-developed test called the Oncotype DX Breast Recurrence Score^® test. The results helped her confidently make the decision to avoid chemotherapy and preserve her career as one of only a few female airline captains in the world at the time. She wanted the same clarity, that same peace of mind, for her friend.

The pair learned that the Oncodetect test looks for tiny traces of cancer DNA that may remain in the body after treatment. Kristi craved that certainty. She messaged her doctor, got the test ordered, completed the blood draw easily from home, and breathed a sigh of relief when she received the results.

“That report came back totally clean,” said Kristi. “I felt so good… it was just amazing.”

That moment changed everything. After receiving her results, Kristi bought herself a ring with three stones, each representing a powerful new mantra.

“It stands for ‘I beat cancer!’” Diane exclaimed.

Kristi knows she will continue to monitor for recurrence for years to come. And yes, a small voice still whispers worries now and then. But today, that voice is quieter. It’s no match for the peace of mind she’s gained.

That’s the power of precision medicine. That’s the power of knowing.

What is MRD testing, and why is it on the rise?

For many cancer patients, finishing treatment marks the beginning of an unexpected emotional chapter. The pace of care changes quickly once treatment ends. The regular interactions with nurses, clinicians, and caregivers slow down, creating a noticeable shift for many patients. The plan, which was so clear and structured during treatment, suddenly dissolves. What remains is what University of Wisconsin cancer psychologist Dr. Lori DuBenske calls “ambiguity.”

“You don’t feel done; you don’t feel well yet,” said Dr. DuBenske. “And there’s a lot of ambiguity that comes with that time point… and then comes the fear of recurrence: ‘What if it comes back?’ ‘How do we even know it’s gone?’”

MRD testing is a rapidly growing approach designed to answer these questions.

The Oncodetect test, for example, identifies tiny fragments of tumor DNA that may remain in the bloodstream after treatment (surgery, chemotherapy, immunotherapy or targeted therapy). This test provides a personalized, highly sensitive way to monitor for signs of recurrence before symptoms occur and up to two years earlier than traditional imaging can detect it.² For cancers like triple negative breast cancer, where recurrence can be aggressive and swift, early detection becomes even more critical.³

This technology is rising in prominence because it offers what survivors crave most: insights into a patient’s specific tumor biology.

“Information is most empowering when we can do something about it,” said Dr. DuBenske.

Why MRD testing is so impactful, emotionally and clinically

The emotional toll of post-treatment life is immense. Patients often expect to feel relieved once chemotherapy or radiation ends, but many experience the opposite.

This is one area where MRD can play a critical role.

For patients like Kristi, the knowledge that someone (or something) is keeping watch can reduce fear and help them build trust in their future. And since cancer can change over time, ongoing MRD testing helps track ctDNA levels and potentially detect changes earlier.²

It can also help patients make decisions with more confidence. Exact Sciences’ Oncodetect test is a tumor-informed test, meaning each individual's tumor is analyzed to create a personalized test.

This matters because survivorship isn’t just physical, it’s deeply psychological.

Kristi describes the early days after treatment as living with a “bigger little voice” in her head, the nagging worry that cancer could return. For her, MRD testing helped minimize the uncertainty.

“That voice has been silenced quite a bit,” said Kristi. “I feel pretty good about it not coming back right away.”

For Diane, who has supported multiple women through cancer, the impact on her friend Kristi was undeniable:

“She looked like a different person. Completely. The peace of mind, it changed everything for her.”

The Promising Future of Precision Oncology

As precision diagnostics advance, survivors like Kristi and advocates like Diane see a future where no one has to navigate life after diagnosis in the dark.

And while MRD testing is still new, its promise is enormous. For doctors, it offers earlier visibility. For researchers, it provides crucial data to design more personalized treatments. For patients, it can restore something often lost after cancer: hope.

Dr. DuBenske notes that the future of precision oncology care must include emotional support alongside scientific breakthroughs.

“If we’re going to give patients information, we have to give them the tools to use it and the support to cope with it,” said Dr. DuBenske.

Exact Sciences is working to build that ecosystem. It’s not simply about finding cancer earlier. It’s about helping patients live more fully after treatment ends.

For Kristi, that future is already beginning.

She exercises daily. She eats with intention. And she can look at the three-stone ring on her finger and remember what she’s overcome.

Knowledge didn’t just give her information. It gave her the power to trust her tomorrow.

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Kristi and Diane are Exact Sciences patient ambassadors

This story reflects one individual’s experience. Not every person will have the same treatment, experience, outcome, or result.

This test was developed, and its performance characteristics determined by Genomic Health, Inc. The Oncodetect test was clinically validated in colorectal cancer patients with stage II-IV disease. Performance characteristics may not apply in tumor types not included in this test’s clinical validation. The test has not been cleared or approved by the US Food and Drug Administration. The test has been validated as a Laboratory Developed Test per institutional and applicable CLIA regulation (CLIA# 03D2048606) and College of American Pathology (CAP# 8869063) as qualified to perform high complexity clinical laboratory testing.

References:

1. Obidiro O, Battogtokh G, Akala EO. Triple Negative Breast Cancer Treatment Options and Limitations: Future Outlook. Pharmaceutics. 2023 Jun 23;15(7):1796. doi: 10.3390/pharmaceutics15071796. PMID: 37513983; PMCID: PMC10384267.

2. Diergaarde B, Young G, Hall DW, Mazloom A, Costa G, Subramaniam S, Palomares M, Garces J, Baehner FL, Schoen RE; and other members of the Exact Sciences MRD Group. Circulating tumor DNA as a marker of recurrence risk in Stage III colorectal cancer: The α‐CORRECT study. Journal of Surgical Oncology.

3. Syeda MF, Santos RA, Sousa LM, et al. Immune monitoring of neoadjuvant chemo-immunotherapy for triple-negative breast cancer. Front Immunol. 2025;16:1654748. Published 2025 Oct 15. doi:10.3389/fimmu.2025.1654748