ROCHESTER, Minn. — Researchers in a Mayo Clinic-led study have shown how to detect a broad range of DNA mutations in noncancerous human tissues and across the genome. The analysis, drawing on more than 90 trillion DNA letters of sequencing data, could help scientists study when these changes arise — from early development through aging — and how they contribute to cancer and other diseases. 

Published in Cell, the study is the flagship paper in a package of roughly a dozen publications from the National Institutes of Health (NIH) Common Fund's Somatic Mosaicism across Human Tissues, or SMaHT, Network. The network includes more than 300 members from more than two dozen U.S. universities and hospitals. Researchers evaluated approaches for detecting somatic mutations ranging from single-letter DNA changes to large deletions, insertions and rearrangements. 

Alexej Abyzov, Ph.D., a Mayo Clinic professor of biomedical informatics who leads the Somatic Mutations in Development and Aging Laboratory, is the corresponding author of the Cell study. 

Reading the cellular mosaic

Unlike inherited genetic changes, somatic mutations arise after conception and accumulate over a lifetime. As cells divide, they can pass those changes to new cells, creating genetic differences within the same person, known as somatic mosaicism. Some somatic mutations can alter how cells behave and contribute to cancer, aging, and neurodevelopmental, cardiovascular and autoimmune diseases. 

These mutations can be difficult to detect when they are rare or occur in complex, repetitive regions of the genome. The SMaHT Network compared short- and long-read whole-genome sequencing, duplex sequencing, single-cell sequencing, and computational approaches. 

One of the clearest findings came from long-read sequencing, which reads longer stretches of DNA at a time. Much like reading a full sentence instead of a few scattered words, the added context made large genetic changes easier to find. Long-read sequencing detected about twice as many large DNA changes as short-read sequencing. It also found insertions that shorter reads often missed. 

Researchers improved detection in other hard-to-read parts of the genome too. In one benchmark, a more complete genome reference raised precision from 79% to 89%. Single-cell sequencing of 102 lung and colon cells revealed differences from cell to cell and helped trace their history back to early development. 

Companion study maps rare mutations across tissues

Dr. Abyzov also co-led a companion SMaHT paper published in The American Journal of Human Genetics. Deep whole-genome sequencing accurately detected rare, single-letter DNA changes present at levels below 1% in a tissue sample. 

Analyzing DNA from different organs also helped detect mutations that arose early in development and spread to multiple tissues. Combining lung and colon data uncovered 13 additional shared mutations, improving detection by 145% for these very rare mutations compared with analyzing either tissue alone. 

SMaHT aims to catalog somatic mutations across 10 to 15 tissue types from 150 donors while improving the tools used to detect them. NIH is planning a second stage focused on understanding how these mutations influence biological processes and disease. 

Dr. Abyzov says the research could eventually help identify people at higher cancer risk and track precancerous changes in tissues before developing symptoms.  

The studies were supported by the NIH Common Fund through the Office of Strategic Coordination in the NIH Office of the Director. The companion study received additional NIH support for work conducted at Mayo Clinic. For complete author lists, disclosures and funding information, review the Cell study and the companion The American Journal of Human Genetics study. 

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About Mayo Clinic   
Mayo Clinic is a nonprofit organization committed to innovation in clinical practice, education and research, and providing compassion, expertise and answers to everyone who needs healing. Visit the Mayo Clinic News Network for additional Mayo Clinic news.   

Media contact:    

• Julie Ferris-Tillman, Ph.D., Mayo Clinic Communications, newsbureau@mayo.edu 

The post Large-scale study advances detection of DNA mutations across the human genome  appeared first on Mayo Clinic News Network.

When part of the liver is removed to treat cancer or other conditions, the remaining tissue must regenerate to restore liver function.  

In this Mayo Clinic Minute, Dr. Patrick Starlinger, a hepatobiliary and pancreas surgeon at Mayo Clinic Comprehensive Cancer Center, discusses research to help the liver regenerate after surgery. 

Watch: The Mayo Clinic Minute

Journalists: Broadcast-quality video (1:07) is in the downloads at the end of this post. Please courtesy: "Mayo Clinic News Network." Read the script.

How does the liver regenerate after surgery?

"The liver can regenerate quite dramatically, probably the most potential to regenerate in the entire human body, and we leverage this in liver surgery," says Dr. Starlinger.  

Before surgery, the team measures liver volume and assesses liver function to determine how much can be safely removed to take out the tumor while leaving enough healthy liver to regenerate.  

But in some patients, that regeneration does not happen, which can lead to liver failure and limit which tumors can be removed.  

"Our area of research is so important to understand the mechanism of liver regeneration in humans, particularly because as we understand the mechanism, we can move forward with interventions to promote regeneration in these patients," says Dr. Starlinger.  

What role does blood clotting play in liver regeneration?

Mayo Clinic researchers have analyzed liver samples from patients with healthy livers and those with underlying liver conditions to better understand what drives regeneration.   

"We were able to discover that the blood coagulation system is crucially important to allow these mechanisms of liver regeneration to actually occur," says Dr. Starlinger.     

More research is needed, but researchers hope these findings could eventually lead to treatments that promote liver regeneration and expand the limits of liver surgery.

The post Mayo Clinic Minute: Unlocking how the liver regenerates after surgery (VIDEO) appeared first on Mayo Clinic News Network.

Landmark ATOMIC trial brings immunotherapy to patients being treated with the goal of cure

ROCHESTER, Minn. — The Food and Drug Administration (FDA) has approved the immunotherapy drug atezolizumab in combination with chemotherapy for some patients with stage 3 colon cancer following surgery. The treatment is for patients whose tumors have deficient DNA mismatch repair, or dMMR.

The approval is based on results from the ATOMIC clinical trial led by Mayo Clinic. The study found that adding atezolizumab to standard chemotherapy reduced the risk of cancer recurrence or death by 50% compared with chemotherapy alone. FDA approval further establishes the addition of immunotherapy to chemotherapy as a standard treatment option in the curative setting and helps to make it more readily accessible to patients who may benefit.

"This approval represents a major advance for patients with a subset of stage 3 colon cancer," says Frank Sinicrope, M.D., a Mayo Clinic oncologist and leader of the ATOMIC study. "ATOMIC is the first study to show the benefit of immunotherapy after surgical resection in patients with locally advanced colon cancer with dMMR. The goal after surgery is to eliminate remaining microscopic cancer cells responsible for recurrence and thereby increase the number of patients who are cured of their disease."

The phase 3 ATOMIC trial enrolled 712 patients with stage 3 dMMR colon cancer that had been surgically removed and spread to regional lymph nodes. Patients were randomly assigned to receive standard chemotherapy alone or chemotherapy combined with atezolizumab, an immune checkpoint inhibitor, followed by additional atezolizumab.

At three years, 86.3% of patients who received immunotherapy plus chemotherapy were alive and free of disease, compared with 76.2% of patients who received chemotherapy alone. The findings were published this year in The New England Journal of Medicine.

Moving immunotherapy earlier in treatment

Immune checkpoint inhibitors have transformed the treatment for several advanced cancers. In colon cancer, they have been particularly effective against tumors with dMMR. These tumors have a defect in their ability to properly repair errors in their DNA during cell division, leading to the accumulation of multiple mutations that can make the cells more recognizable to the immune system.

Before the ATOMIC trial, immunotherapy was used primarily for advanced or metastatic dMMR colorectal cancer. ATOMIC examined whether activating the immune system after surgery that is intended to cure the patient could prevent cancer from returning.

"Instead of waiting until a patient's colon cancer has returned or spread, we can now use immunotherapy earlier when patients have undergone surgery and are able to prevent or markedly reduce the chance of recurrence," Dr. Sinicrope says.

Approximately 15% of colon cancers have dMMR. Testing a patient's tumor can identify dMMR and help determine the optimal treatment.

An important advance for younger patients

The approval also comes as colorectal cancer rates among younger adults continue to rise. More than one-quarter of patients enrolled in ATOMIC were younger than 50.

The trial included patients with Lynch syndrome, the most common inherited cause of colorectal cancer and the most common hereditary cancer syndrome. People with Lynch syndrome have an increased risk of developing several cancers, particularly colorectal cancer, and frequently develop cancer at younger ages. Colon cancers associated with Lynch syndrome generally have dMMR.

"For patients who develop colon cancer at a young age, preventing recurrence can translate into decades of life gained," Dr. Sinicrope says. "Being able to offer an effective treatment such as immunotherapy to improve the survival of these patients is especially meaningful for them and their families."

From scientific insight to a new treatment

ATOMIC grew from years of research into the biology of dMMR colon cancer. Dr. Sinicrope and colleagues previously observed that these tumors contain large numbers of inflammatory and immune cells, including those cells targeted by immune checkpoint inhibitors. Those findings provided the scientific rationale for testing whether immunotherapy could strengthen the body's immune response against cancer cells that can remain after surgery.

Dr. Sinicrope developed the study, which was conducted through the Alliance for Clinical Trials in Oncology, part of the National Cancer Institute-supported National Clinical Trials Network. Patients from the U.S. and Germany participated.

"The patients who participated in ATOMIC made this advance possible, and their contribution will change how we treat patients with dMMR colon cancer here and around the world," says Dr. Sinicrope.

The National Comprehensive Cancer Network previously updated its guidelines to include atezolizumab plus chemotherapy as a treatment option based on the ATOMIC findings. FDA approval establishes the regimen as an approved treatment for eligible patients in the U.S.

The National Cancer Institute of the National Institutes of Health and Genentech funded the ATOMIC study. See the study in The New England Journal of Medicine for a complete list of authors, disclosures and funding.

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About Mayo Clinic
Mayo Clinic is a nonprofit organization committed to innovation in clinical practice, education and research, and providing compassion, expertise and answers to everyone who needs healing. Visit the Mayo Clinic News Network for additional Mayo Clinic news.

Media contact:

• Julie Ferris-Tillman, Ph.D., Mayo Clinic Communications, newsbureau@mayo.edu

The post FDA approves immunotherapy regimen studied by Mayo Clinic for stage 3 colon cancer appeared first on Mayo Clinic News Network.

This aggressive brain cancer can extend beyond what's visible on a standard MRI, making it difficult to precisely target treatment. Just 5% to 7% of patients survive five years after diagnosis. 

Mayo Clinic researchers are studying advanced imaging techniques designed to bring more of the tumor into view and potentially give care teams a better-defined target. 

"We're trying to develop and improve treatments that will help extend the length of time patients live, as well as their quality of life and function while they're alive," says Dr. William Breen, a radiation oncologist at Mayo Clinic. "From a radiation perspective, we need to be able to accurately see the tumor to accurately target it and treat it as well as possible." 

Watch: The Mayo Clinic Minute

Journalists: Broadcast-quality video (1:04) is in the downloads at the end of this post. Please courtesy: "Mayo Clinic News Network." Read the script.

Seeing tumors more clearly 

A standard MRI with contrast shows doctors where glioblastoma appears to be, but tumor cells can extend into the surrounding brain beyond what is clearly visible. 

"In over half of patients, we find a tumor more than a centimeter beyond the standard MRI-defined tumor, and in 20% of patients, we find a tumor more than 2 centimeters beyond the standard MRI-identified tumor," Dr. Breen says. 

To see more, Mayo Clinic investigators are combining advanced MRI techniques with research PET scans. The scans provide different clues, such as areas where cells are especially dense, where blood flow is increased or where there may be more aggressive tumor activity. 

Together, they can give doctors a more detailed picture of the tumor and where it may extend. 

Treating tumors more precisely and effectively 

Because glioblastoma can extend beyond what doctors see on a traditional MRI, radiation treatment generally includes an extra margin around the visible tumor to help cover cancer cells that may be hidden. 

Advanced imaging could help doctors more accurately identify those areas and tailor radiation accordingly. For some patients, that could mean treating a smaller area of the brain and reducing radiation exposure to healthy tissue. 

"By using advanced imaging, we're able to treat a smaller area in many patients and reduce the amount of normal brain receiving radiation, which may make for a safer and better treatment," Dr. Breen says. 

Researchers also are studying whether they can direct more intensive treatment toward areas that advanced imaging identifies as particularly concerning. 

Greater precision may make it possible to give a higher dose of radiation at each treatment and finish therapy sooner. Dr. Breen says treatment has been shortened from three to six weeks to one to two weeks for some patients, meaning fewer trips to the hospital and more time at home. 

Bringing specialties together 

The research brings together experts across Mayo Clinic, including neurosurgeons, radiation oncologists, neuro-oncologists, neuroradiologists and nuclear medicine specialists. 

"I think our strength at Mayo Clinic for treating glioblastoma is the multidisciplinary team," Dr. Breen says. 

While glioblastoma remains challenging to treat, advances in imaging, surgery, radiation, chemotherapy and other therapies are helping researchers continue to improve care. 

"We know there's still much progress to be made," Dr. Breen says, "but we have seen progress over the years to improve both quality of life and quantity of life for our patients with glioblastomas."

The post Mayo Clinic Minute: Seeing glioblastoma more clearly could improve how it’s treated appeared first on Mayo Clinic News Network.

Mayo Clinic findings also link specific gut bacteria to cancer survival and identify a pretreatment signal associated with chemotherapy toxicity

ROCHESTER, Minn. — Mayo Clinic researchers have discovered distinct gut microbiome patterns in adults age 50 or younger with colorectal and breast cancers compared with those diagnosed later in life — one of several findings from an analysis of stool samples from 1,364 patients with cancer across cancer types, stages and treatments.

Among younger patients, those with colorectal cancer had higher lactate levels and more Veillonella parvula, a gut bacterium that feeds on lactate. Early-onset breast cancer showed changes across 64 bacterial species and lower levels of primary bile acids.

Published in Cell, the findings come from the Mayo Clinic Cancer Microbiome cohort, a real-world study that recruited cancer patients at Mayo Clinic in Arizona, Florida and Minnesota, representing 40 states. Stool samples were collected before patients began a new treatment regimen and linked to detailed clinical data on side effects and outcomes. The samples provided a window into the gut microbiome — the trillions of microbes living in the digestive tract.

Cancer-specific microbiome patterns emerge

Researchers first compared patients with cancer with 287 people without cancer to identify broad microbiome differences. Comparisons across cancer types then revealed more specific signals. After accounting for other health conditions, researchers pinpointed 341 bacterial species associated with five cancer groups.

Among those groups, neuroendocrine tumors showed a broad loss of common, health-associated gut bacteria. Liver and intrahepatic bile duct cancers had higher levels of several bacteria, including Enterococcus faecalis, while esophageal cancer had higher levels of six species, including several Streptococcus bacteria. Distinct associations were also found in lymphoid leukemia and multiple myeloma and related plasma cell cancers.

Distinct patterns in early-onset cancers 

The findings come as colorectal and breast cancer rates rise among younger adults. Colorectal cancer incidence is increasing about 3% a year among adults ages 20 to 49, while breast cancer incidence is rising 1.4% a year among women younger than 50, according to the American Cancer Society.

The colorectal finding raises questions about a possible biological connection: Tumors can produce high levels of lactate, which Veillonella parvula uses to grow. Whether that relationship plays a role in early-onset disease is not yet known.

In breast cancer, one of the 64 species that differed in younger patients was Clostridium scindens, a bacterium involved in bile acid and steroid metabolism.

No comparable age-related microbiome differences were found in brain cancer, the third cancer examined in the early-onset analysis. The colorectal and breast cancer findings do not establish that these microbial or metabolic differences cause early-onset disease, but they identify associations that warrant further study.

Gut microbiome linked to survival and treatment side effects 

Researchers also identified specific gut bacteria associated with survival in colorectal, liver and intrahepatic bile duct, melanoma, ovarian and prostate cancers. In liver and intrahepatic bile duct cancer, Bifidobacterium longum was associated with longer survival and Blautia A massiliensis with shorter survival.

Researchers also studied whether the gut microbiome before treatment was associated with diarrhea during chemotherapy, a side effect that can make treatment harder to tolerate. Among patients receiving 5-fluorouracil, or 5-FU, a chemotherapy used to treat many types of cancer, those who later developed diarrhea had lower levels of bacterial genes capable of breaking down the drug. Much of that function came from Anaerostipes hadrus, a common gut bacterium.

The same signal was not linked to diarrhea in patients receiving carboplatin, another chemotherapy drug, suggesting the finding was specific to 5-FU.

"The microbiome is not the sole driver of cancer or treatment outcomes, but it is an underappreciated component that has not traditionally been considered in therapeutic approaches," says senior author Purna Kashyap, M.B.B.S., a gastroenterologist, director of the Mayo Clinic Microbiome Program and Bernard and Edith Waterman Director, Microbiomics Program, Mayo Clinic Center for Individualized Medicine. "This gives us a proof of concept that we can begin to understand why some patients experience a particular side effect and identify a target that could potentially be acted upon."

Next, researchers will investigate whether cancer-specific microbial signals play a causal role in disease and validate the microbiome's potential to predict treatment side effects in larger patient groups.

The research was supported in part by the National Institutes of Health and philanthropic gifts from the Valhalla Foundation, the Maxine & Jack Zarrow Family Foundation, and other benefactors to the Mayo Clinic Microbiome Program and Center for Individualized Medicine.

Jun Chen, Ph.D., professor of biostatistics and consultant in Mayo Clinic’s Division of Computational Biology, is also a co-corresponding author. For a complete list of authors, disclosures and funding, review the study. 

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About Mayo Clinic  
Mayo Clinic is a nonprofit organization committed to innovation in clinical practice, education and research, and providing compassion, expertise and answers to everyone who needs healing. Visit the Mayo Clinic News Network for additional Mayo Clinic news.  

Media contact:   

• Julie Ferris-Tillman, Ph.D., Mayo Clinic Communications, newsbureau@mayo.edu 

The post Distinct gut microbiome patterns found in 5 cancer groups and in early-onset cancers appeared first on Mayo Clinic News Network.

ROCHESTER, Minn. — Mayo Clinic researchers led a multicenter study that found dividing radiation into several treatments, known as fractionated stereotactic radiosurgery, reduced the risk of cancer returning after surgery for brain metastases and was associated with improved survival compared with delivering radiation in a single treatment.

The findings are being presented today at the 2026 American Society for Radiation Oncology (ASTRO) Annual Meeting in Boston.

Brain metastases, also called metastatic brain tumors, are cancerous tumors that spread to the brain from elsewhere in the body. Radiation therapy is a standard treatment after surgery, but researchers note that about 30% to 40% of patients experience cancer recurrence at the surgical site despite treatment with single fraction radiosurgery.

"The study findings give us the evidence necessary to transform clinical practice. We can now offer patients a treatment that controls their disease and is associated with improved survival," says Paul D. Brown, M.D., radiation oncologist at Mayo Clinic Comprehensive Cancer Center and co-principal investigator of the study.  

Why dividing radiation may improve outcomes

Stereotactic radiosurgery uses 3D imaging to precisely deliver high doses of radiation while limiting exposure to surrounding healthy tissue. It is typically delivered in a single treatment and is commonly used to treat brain metastases.

"We see high recurrence rates in patients with brain metastases because the challenge is eliminating microscopic cancer cells left behind after surgery without exposing too much healthy brain tissue to high doses of radiation," says Dr. Brown.

Dividing radiation into multiple treatments allows clinicians to deliver a higher total dose. It also gives healthy tissue time to recover between treatments, while tumor cells do not have the same ability to repair.  

Previous retrospective studies have suggested that fractionated stereotactic radiosurgery is effective, but the approach had not been validated in a randomized clinical trial.

How researchers studied fractionated radiosurgery

The study enrolled 242 patients with one to four brain metastases. Each patient had at least one metastasis larger than 2 centimeters that had been surgically removed.

Patients were randomly assigned to receive either a single treatment of stereotactic radiosurgery or fractionated stereotactic radiosurgery delivered in three or five treatments. Radiation doses were based on the size of the treatment area. Brain metastases that had not been surgically removed were treated according to the same assigned schedule.

Researchers followed patients for a median of four years.

One year after treatment, 87% of patients who received fractionated stereotactic radiosurgery had no recurrence at the surgical site, compared with 81% of patients who received a single treatment. Fractionated radiosurgery also better controlled brain metastases that had not been surgically removed, although this result was not statistically significant.

Median overall survival was 29 months for patients who received fractionated stereotactic radiosurgery, compared with 20 months for patients who received a single treatment. Fractionated treatment was associated with a 31% lower risk of death.

"The survival benefit was an unexpected finding, and while the exact mechanism remains unclear, we suspect that advances in systemic therapies over the past decade may be interacting with better control of disease within the brain, and overall, better outcomes for patients," says Dr. Brown.

Researchers found no difference in side effects or complications between the two treatment approaches.

"This is a practice-changing clinical trial in our field, demonstrating that fractionated radiosurgery not only reduces recurrence after surgery for large brain metastases but may also improve overall survival," says Robert Mutter, M.D., chair of research in the Department of Radiation Oncology and co-leader of the Novel Therapeutics and Therapeutic Modalities Research Program at Mayo Clinic Comprehensive Cancer Center. 

For more information, funding and authors, read the ASTRO abstract.

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About Mayo Clinic
Mayo Clinic is a nonprofit organization committed to innovation in clinical practice, education and research, and providing compassion, expertise and answers to everyone who needs healing. Visit the Mayo Clinic News Network for additional Mayo Clinic news.

About Mayo Clinic Comprehensive Cancer Center
Designated as a comprehensive cancer center by the National Cancer Institute, Mayo Clinic Comprehensive Cancer Center is defining the cancer center of the future, focused on delivering the world's most exceptional patient-centered cancer care for everyone. At Mayo Clinic Comprehensive Cancer Center, a culture of innovation and collaboration is driving research breakthroughs in cancer detection, prevention and treatment to change lives.

Media contact:

• Julie Ferris-Tilman, Ph.D., Mayo Clinic Communications, newsbureau@mayo.edu

The post Study finds fractionated radiosurgery reduces recurrence after surgery for brain metastases, may improve survival appeared first on Mayo Clinic News Network.

ROCHESTER, Minn. — Mayo Clinic researchers will present findings on emerging technologies, precision treatments and new radiation therapy techniques at the 2026 American Society for Radiation Oncology (ASTRO) Annual Meeting, Sept. 26–30 in Boston.

Mayo Clinic experts will participate in nearly 65 poster, education, quick-pitch, scientific, oral, plenary and presidential sessions and present 45 abstracts. Their presentations will cover topics ranging from artificial intelligence (AI) and advanced technologies in radiation therapy to clinical outcomes of precision treatments and novel techniques.

Meeting highlights include:

Presidential Symposium: Data to Dialogue: Communicating Radiotherapy's Value to Advance Care - Session II: Challenges and Opportunities in Scientific Knowledge Creation and Dissemination
Presentation time: Sunday, Sept. 27, 9:49–9:53 a.m. EDT
Description: This session will explore how today's science and healthcare information will be disseminated tomorrow, and look at the roles of journals, websites, online platforms and AI-powered content.
Panelist: John D. Halamka, M.D., Dwight and Dian Diercks president, Mayo Clinic Platform

Scientific Session: Clinical Trials Session
Presentation time: Sunday, Sept. 27, 2:10–2:20 p.m. EDT
Presentation title: Stereotactic Body Radiation Therapy (SBRT) and Comprehensive Metastasis-Directed Therapy for Ewing Sarcoma Patients Enrolled on AEWS1221: A Report from the Children's Oncology Group (COG)
Description: The study examines the feasibility and safety of SBRT and comprehensive metastasis-directed therapy for patients with metastatic Ewing sarcoma. Researchers report the highest event-free survival to date in cooperative-group trials of metastatic Ewing sarcoma.
Presenter: Nadia Laack, M.D., radiation oncologist, Mayo Clinic Comprehensive Cancer Center in Rochester

Education Session: Artificial Intelligence, Robotics and Emerging Technologies in Gynecologic Radiation Oncology: From Automation to Precision Delivery
Presentation time: Sunday, Sept. 27, 3:02–3:17 p.m. EDT
Presentation title: AI-Driven Automation in Pelvic Radiation Therapy: From Contouring to Plan Optimization
Description: The presentation explores prediction-guided care, including the use of artificial intelligence to identify each patient's risk of side effects and help physicians make more personalized treatment decisions.
Presenter: Andres Portocarrero Bonifaz, Ph.D., radiation oncology medical physicist, Mayo Clinic in Florida

Quick Pitch: Neurocognition and Novel Therapies in Glioma
Presentation time: Monday, Sept. 28, 8:25–8:30 a.m. EDT
Presentation title: Patterns of Failure After 18F-DOPA PET and MRI–Guided Hypofractionated Proton Therapy in Older Adults with Glioblastoma
Description: Researchers will present patterns of radiographic failure at the first progression of glioblastoma in older adults treated with hypofractionated proton therapy guided by 18F-DOPA PET and MRI.
Presenter: Diego Santos Toesca, M.D., radiation oncologist, Mayo Clinic in Arizona

Education Session: Spatially Fractionated Radiation Therapy (SFRT): Biological Mechanisms and Clinical Translation
Presentation time: Monday, Sept. 28, 8:32–8:47 a.m. EDT
Presentation title: Delivering Minibeam Radiotherapy: Clinical Workflow and Translational Insights
Description: The presentation will share results from Mayo Clinic's first-in-human clinical translation of minibeam radiotherapy. Read the news release.
Presenter: Michael Grams, Ph.D.,  radiation oncology medical physicist, Mayo Clinic Comprehensive Cancer Center in Rochester

Oral Session: Patient Reported Outcomes/QoL/Survivorship
Presentation time: Monday, Sept. 28, 8:32–8:47 a.m. EDT
Presentation title: Comparative Prognostic Value of Disease Specific Patient Reported Outcomes in Prostate Cancer
Description: The study compares how well patient-reported outcome measures predict overall survival, with the goal of informing evidence-based selection of these measures in prostate cancer.
Presenter: Minji Lee, Ph.D., scientist in radiation oncology, Mayo Clinic in Rochester

Scientific Session: Some crHEME with Your Coffee? A Winning Blend of Radiation and Systemic Therapy in Hematologic Malignancies
Presentation time: Monday, Sept. 28, 11:15–11:25 a.m. EDT
Presentation title: Safety of Maintenance Pembrolizumab (Pembro) and Concurrent Radiotherapy (RT) in Pediatric Participants with Classic Hodgkin Lymphoma (cHL) and Slow Early Response (SER) to Front-Line Chemotherapy (Chemo): Post Hoc Analysis of the KEYNOTE-667 Study
Description: Researchers evaluated the safety of concurrent immunotherapy and radiation therapy in pediatric patients with Hodgkin lymphoma who were treated as part of a chemo-immunotherapy study.
Presenter: Brad Hoppe, M.D., radiation oncologist, Mayo Clinic Comprehensive Cancer Center in Florida

Plenary Session
Presentation time: Monday, Sept. 28, 2:04–2:13 p.m. EDT
Presentation title: Alliance A071801 Phase III Trial Postoperative Single Fraction Stereotactic Radiosurgery (SRS) vs. Fractionated SRS (fSRS) for Resected Brain Metastasis
Description: Researchers report findings from a randomized trial comparing fSRS with single-fraction SRS for resected brain metastases.
Principal investigator: Paul D. Brown, M.D., radiation oncologist, Mayo Clinic Comprehensive Cancer Center in Rochester

Scientific Session: Optimizing Therapy, Toxicity, and Supportive Care in Head and Neck Cancers
Presentation time: Tuesday, Sept. 29, 12:57–1:06 p.m. EDT
Presentation title: First Report from the Headlight Trials: Postoperative Hypofractionated Proton Therapy for Head and Neck Cancers Unrelated to HPV
Description: Researchers will report results from clinical trials evaluating a shorter course of proton therapy for head and neck cancer.
Presenter: Scott Lester, M.D., radiation oncologist, Mayo Clinic Comprehensive Cancer Center in Rochester

Scientific Session: The Automated Clinic: AI-Powered Contouring, Monitoring, and Data Extraction
Presentation time: Tuesday, Sept. 29, 2:25–3:35 p.m. EDT
Presentation title: Personalizing PSA Follow-Up after Prostate Radiation Therapy: Developing a Patient-Specific AI-Powered Predictive Model for Clinically Meaningful Recurrence
Description: Researchers developed a machine-learning model that uses patient-specific clinical data and prostate-specific antigen kinetics to predict prostate cancer recurrence after definitive radiation therapy.
Presenter: Mariana Borras-Osorio, M.D., research fellow in radiation oncology, Mayo Clinic in Rochester

Learn more about ASTRO 2026.

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About Mayo Clinic
Mayo Clinic is a nonprofit organization committed to innovation in clinical practice, education and research, and providing compassion, expertise and answers to everyone who needs healing. Visit the Mayo Clinic News Network for additional Mayo Clinic news.

About Mayo Clinic Comprehensive Cancer Center
Designated as a comprehensive cancer center by the National Cancer Institute, Mayo Clinic Comprehensive Cancer Center is defining the cancer center of the future, focused on delivering the world's most exceptional patient-centered cancer care for everyone. At Mayo Clinic Comprehensive Cancer Center, a culture of innovation and collaboration is driving research breakthroughs in cancer detection, prevention and treatment to change lives.

Media contact:

• Julie Ferris-Tillman, Ph.D., Mayo Clinic Communications, newsbureau@mayo.edu

The post Mayo Clinic experts present radiation oncology research at ASTRO 2026 appeared first on Mayo Clinic News Network.

Watch: the Mayo Clinic Minute

Journalists: Broadcast-quality video (1:09) is in the downloads at the end of this post. Please courtesy: "Mayo Clinic News Network." Read the script.

Unlike many cancers that form solid tumors, leukemia is a cancer of the blood-forming cells in the bone marrow.

Dr. Arana Yi says, "Leukemia affects the production of the blood cells and can circulate through all the body from the beginning." 

Leukemia isn't a single disease. There are several types that can behave differently. According to Dr. Arana Yi, "It is a group of cancers with different subtypes. Some develop very quickly, while others progress slowly." 

Leukemia can affect people of all ages. Symptoms can include persistent fatigue, unusual bruising or bleeding, frequent infections, fever, night sweats, unexplained weight loss and shortness of breath. 

"If those are persistent, it is important to review and be evaluated by a doctor for a possibility of a blood count checkup," Dr. Arana Yi mentions. 

Research is helping doctors identify genetic changes that may be driving a patient's leukemia. That information can help guide treatment. 

Dr. Arana Yi says, "This allows us to use targeted medicines, immune-based therapies, sometimes with less traditional chemotherapy or chemo-free regimen." 

Recognizing possible symptoms and seeking medical evaluation can help doctors diagnose leukemia and determine appropriate treatment. 

"Recognizing symptoms since the beginning, and early evaluation with the doctors is key to diagnose the acute leukemia as soon as possible," Dr. Arana Yi concludes. 

The post Mayo Clinic Minute: Leukemia isn’t like other cancers (VIDEO) appeared first on Mayo Clinic News Network.

ROCHESTER, Minn. — A large prospective study published today in Nature Medicine found that a blood test designed to detect multiple cancers identified cancer signals across 17 broad cancer types, such as ovarian, lung, breast and colorectal cancers, and many which do not have recommended screening tests.

Mayo Clinic was among the institutions participating in the prospective, interventional study, which enrolled 35,878 adults age 50 and older. Karthik Giridhar, M.D., a Mayo Clinic medical oncologist, was a study investigator and senior author.

The multicancer early detection (MCED) test analyzes small fragments of DNA that cells release into the bloodstream. Researchers use patterns in these fragments to detect signals associated with cancer. When a cancer signal is detected, the test also predicts the likely location of the cancer to help physicians determine appropriate follow-up testing.

Among 32,007 participants included in the study's performance analysis, 287 had a positive MCED test result. Cancer was diagnosed in 173 of those participants. The test had a positive predictive value of 60.3% and specificity of 99.64%. Among participants with a true-positive result, the test correctly predicted one of the two most likely cancer signal origins in 91.3% of cases.

"One of the challenges in cancer screening is that most cancers do not have an established screening test," says Dr. Giridhar. "This study helps us better understand how a multicancer blood test might complement existing screening approaches by identifying cancer signals that otherwise may not be detected through routine screening."

Researchers found that 72.8% of cancers detected by the MCED test were cancer types without U.S. Preventive Services Task Force grade A or B screening recommendations. Among the 151 participants with at least one newly diagnosed primary cancer detected by the test, 53% had stage 1 or 2 disease and 70.9% had stage 1, 2 or 3 disease.

Giridhar also notes that these tests are not yet a substitute for established cancer screenings. Instead, they may supplement existing screening approaches and help expand understanding of cancer detection.

PATHFINDER 2 was a single-arm study, and its endpoints were descriptive, with no comparator group or formal hypothesis testing. The authors say randomized trials and further follow-up are needed to determine the clinical utility of MCED testing in routine clinical practice. The study also used an earlier version of the test that has since been replaced by a commercially available version.

The study was designed and funded by GRAIL Inc., which also participated in data analysis and interpretation and preparation of the manuscript. Dr. Giridhar reports consulting and advisory relationships with GRAIL and other organizations and travel expenses from GRAIL. A complete list of author disclosures is included in the published study.

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About Mayo Clinic
Mayo Clinic is a nonprofit organization committed to innovation in clinical practice, education and research, and providing compassion, expertise and answers to everyone who needs healing. Visit the Mayo Clinic News Network for additional Mayo Clinic news.

Media contact:

• Julie Ferris-Tillman, Ph.D., Mayo Clinic Communications, newsbureau@mayo.edu

The post Multicancer blood test detects 17 cancer types in large prospective study appeared first on Mayo Clinic News Network.

ROCHESTER, Minn. — Mayo Clinic researchers have identified a strategy that could help chimeric antigen receptor-T cell therapy, or CAR-T cell therapy, overcome a major barrier to treating solid tumors: Cancer cells can change in ways that allow them to hide from immune cells designed to attack them.

In a preclinical study published in Molecular Cancer, researchers found that drugs used to treat advanced thyroid cancer can restore a marker on aggressive thyroid cancer cells, making the cancer visible again to specially engineered CAR-T cells. Combining the drugs with CAR-T cell therapy resulted in better tumor control and survival in preclinical models than either approach alone.

Rather than further modifying CAR-T cells to recognize cancers that have lost their targets, researchers sought to change the tumor so the target reappears.

"We often think about engineering the immune cell to overcome resistance," says co-senior author Saad Kenderian, M.B., Ch.B., a hematologist and oncologist at Mayo Clinic in Minnesota. "This work shows another possibility."

Making an aggressive cancer visible again

CAR-T cell therapy engineers T cells — immune cells that help protect the body from disease — to recognize a specific target, or antigen, on cancer cells. The approach has transformed treatment for some blood cancers but has been less successful against solid tumors.

One reason is that solid tumors can lose or reduce the antigens CAR-T cells are designed to recognize, making it more difficult for the engineered cells to identify and destroy the cancer.

The Mayo Clinic team focused on the thyroid-stimulating hormone receptor (TSHR), a protein found primarily on thyroid cells. CAR-T cells targeting this receptor showed strong antitumor activity against thyroid cancers with high TSHR levels. Their effectiveness was more limited against anaplastic thyroid cancer, the most aggressive form of the disease with low or no TSHR expression.

Turning the target back on

Researchers investigated whether they could restore TSHR through a process known as redifferentiation, in which aggressive cancer cells regain some of the biological features they had lost.

They used drugs that inhibit the mitogen activated protein kinase (MAPK) signaling pathway, including trametinib and dabrafenib, which are approved to treat advanced thyroid cancer.

In patient-derived models of anaplastic thyroid cancer, MAPK inhibition increased TSHR expression on tumor cells. When researchers combined the drugs with TSHR-targeted CAR-T cells, the combination produced stronger tumor control and survival than either treatment alone.

"One of the key discoveries from our work is that antigen density matters. We showed that restoring TSHR expression with combination therapy can sensitize aggressive thyroid tumors to CAR-T cell attack, effectively turning a suboptimal target into a more vulnerable one. This approach may provide a new framework for enhancing CAR-T therapies across solid tumors where target expression is limited," says co-first author Claudia Manriquez Roman, Ph.D., process development engineer at Mayo Clinic in Minnesota.

Researchers also found that the MAPK inhibitors did not appear to interfere with the CAR-T cells' ability to multiply or attack cancer cells. Instead, the drugs created a temporary window in which  the CAR-T cells could target cancer cells that had previously escaped detection.

TSHR expression declined after MAPK inhibitor treatment stopped, but two weeks of concurrent treatment was sufficient to improve CAR-T cell activity in the preclinical models.

"What’s exciting about this approach is that we're taking advantage of the cancer cell's own biology to restore TSHR expression by blocking MAPK signaling with molecular targeted drugs," says co-senior author John Copland III, Ph.D., cancer biologist and translational researcher at Mayo Clinic in Florida. Dr. Copland noted that approximately 2,500 Americans die per year from metastatic thyroid cancer disease. 

A potential strategy beyond thyroid cancer

Although the study focused on thyroid cancer, the concept could have implications for other solid tumors where treatments use immune therapy that targets similar surface markers.

Researchers are completing studies needed to support phase 1 clinical trial testing of TSHR-targeted CAR-T cells. The therapy could be studied alone in patients whose tumors continue to express TSHR or in combination with MAPK inhibitors in patients whose tumors have lost TSHR expression.

The researchers hope the approach ultimately could lead to another treatment option for patients with cancers that no longer respond to available therapies.  

For a complete list of authors, disclosures and funding, read the study.

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Media contact:

• Julie Ferris-Tillman, Ph.D., Mayo Clinic Communications, newsbureau@mayo.edu

The post Study shows reprogramming thyroid tumors may improve CAR-T cell therapy appeared first on Mayo Clinic News Network.