Mayo research using DNA to catch cancer, other medical conditions earlier

By Adam Harringa

What would happen if a certain percentage of serious medical conditions, including cancer diagnoses, were found significantly earlier by studying the entire genome of patients' DNA? How would their quality of life improve, and how many fewer cancer deaths would there be each year?

That's what a group of Mayo Clinic scientists and clinicians aim to find out in the next phase of their genomic research.

"If this strategy is proven cost-effective, then it will likely inform coverage decisions positively by both commercial insurers and government payers, which would be key to large-scale adoption of such a strategy," says Bijan Borah, Ph.D., a health economist and econometrician in the Mayo Clinic Robert D. and Patricia E. Kern Center for the Science of Health Care Delivery.

The research is part of an ongoing project aimed at studying the genetic risk factors that impact medical care of patients at Mayo Clinic and beyond. The latest project, led by the Mayo Clinic Center for Individualized Medicine (CIM), is also supported by Dr. Borah and his team in the Kern Center for the Science of Health Care Delivery, which will examine costs associated with this approach. The overall goal of the genomic project is to accelerate discoveries in individualized medicine to tailor prevention, diagnosis and treatment to a patient's unique genetic makeup.

The large, collaborative team is using the project to examine a racially and ethnically diverse group of 100,000 participants across all Mayo Clinic campuses to ultimately find those who have one of four health conditions: hereditary breast or ovarian cancer, an inherited form of high cholesterol called familial hypercholesterolemia, and Lynch syndrome genes (a genetic disorder that increases the risk of colon and rectal cancer). The researchers will examine the short-term costs, and the long-term cost-effectiveness and life expectancy for those who are found positive for one of the traits. Then, they will use their findings to estimate the long-term cost-effectiveness for the U.S. population. The genetic testing is done through Helix Labs, a population genomics company.

The researchers chose the four conditions based on a Centers for Disease Control and Prevention (CDC) list of 11 Tier 1 genes to focus on people with one or more of those 11 gene mutations, which includes an estimated 2 million people in the U.S.at an increased risk for cancer and other conditions, the CDC reports.

Entire genomic sequencing, or whole exome sequencing, has come a long way in the last two decades. The first genomic sequencing took place in 2003 and cost somewhere between $500 million and $1 billion, the researchers note. However, in the last decade, the emergence of "next-generation sequencing" has dropped the price below $1,000, according to the National Institutes of Health (NIH).

For several years, Mayo Clinic has used genomic sequencing to identify patients who may be at a higher risk for serious conditions, such as cancer, and raised awareness of disparities for some racial groups in genomic data. For more than two years, researchers have been using this data to improve patient care, hoping this can someday be applied to the population level. The research has already led several patients to take preventive measures and another to an early diagnosis of colon cancer, two of many such examples.

"Evidence on the relative cost-effectiveness of whole exome sequencing will soon be required to inform the translation of these technologies into clinical practice," says Niloy Jewel Samadder, M.D., a Mayo Clinic Cancer Center gastroenterologist and clinical genomics specialist. "However, there is a paucity of cost-effectiveness data and especially using measures of clinical utility since most genomic sequencing studies to date have focused on diagnostic success."

About a year ago, Dr. Samadder and his CIM colleagues tapped Dr. Borah and others in the Kern Center for the Science of Health Care Delivery to help with the next step toward translating this research into the medical practice. Dr. Borah calls the work the two Mayo Clinic research centers are completing a symbiotic collaboration.

"There was an ability to synergize the expertise of both centers, building knowledge and career development with people trained in both disciplines," adds Dr. Samadder.

Dr. Borah and his team will examine health care utilization one year after gene sequencing, including office visits, lab tests, screening procedures and preventive treatments. They also will study the change in health care costs long-term using the Mayo Clinic Cost Data Warehouse, factoring for Medicare reimbursement and adjusting for inflation. Finally, long-term cost-effectiveness will be calculated using a model-based simulation.

"We hypothesize that while the proposed intervention may not be cost-effective in the short run, it will be cost-effective in the long run in which a lifetime perspective is assumed, through improved quality of life and extended life," Dr. Borah says.

If their hypothesis is correct, the project will inform decision-making at Mayo Clinic on the wide adoption of genomic research to detect certain diseases earlier, Dr. Samadder adds.

Dr. Samadder’s germline genetic sequencing studies are collaboratively supported by the Center for Individualized Medicine and the Mayo Clinic Cancer Center. His most recent work extends this research into more diverse populations and is supported by the NCI Cancer Center Support Grant to Mayo Clinic, as well as Mayo Clinic Cancer Center philanthropic funds.

Mayo Clinic is working toward a future where genomics will routinely be incorporated into the care of all patients, so physicians can find diseases earlier and treat them more precisely.

Disclosure: Mayo Clinic has a financial interest in Helix.

This article was originally published on the Mayo Clinic Center for Individualized Medicine blog.

Learn more

Learn more about genetic testing and genome sequencing and the importance of cancer clinical trials.