New blood tests expand cancer screening options
Cancer screening has long been a cornerstone of preventive medicine and is linked to better outcomes.
“The earlier we find cancer, the more likely we are to cure it,” says medical oncologist Kelsey Klute, MD. “We have better treatments for early-stage cancer than late stage.”
Most cancer screening focuses on one type of cancer at a time. For example:
- Breast cancer: Mammogram, MRI.
- Colon cancer: Colonoscopy, stool test.
- Prostate cancer: PSA blood test.
- Lung cancer: CT scan.
- Cervical cancer: Pap smear, HPV test.
These approaches are effective. Dr. Klute points to colorectal cancer screening as a prime example.
“We do colon cancer screening to find early colon cancer,” she says. “But the biggest impact is that you can remove a precancerous polyp and prevent cancer from happening.”
Multicancer detection tests
While traditional screening works well, it only detects one type of cancer. Cancer centers are now exploring new technology that can screen for multiple cancers at once.
“As Nebraska’s only NCI-designated cancer center, we follow strict screening guidelines,” said Joann Sweasy, PhD, director of the Fred & Pamela Buffett Cancer Center.
“We’re also excited about new technology that could find cancers that don’t have recommended screening today.”
Enter multicancer early detection tests like the Galleri® test developed by GRAIL.
“This is a very different test in that it’s designed to detect many types of cancer,” Dr. Klute explains. “Fifty-plus different types of cancer can be detected from one blood test.”
The test works by identifying cell-free DNA that cancer cells release into the blood. It can even suggest where in the body the cancer might be.
But Dr. Klute warns that these new tests don’t replace current screening methods. The low levels of cell-free DNA released by slow-growing cancers – such as prostate and certain breast cancers – reduce their detectability by the Galleri test. The Galleri test has higher sensitivity for aggressive cancers, such as liver and pancreatic, that release a higher amount of cell-free DNA and often don’t have recommended screening options.
A work in progress
The current multicancer detection tests have limitations. Approximately 1% of people age 50 and older will get positive results, and about six out of 10 with a positive result will be diagnosed with cancer after diagnostic testing.
“That false-positive rate is something to consider,” Dr. Klute says. With Galleri, only about one in 250 people without cancer are expected to receive a false positive. The test costs $749 out of pocket, and most insurance plans do not cover it yet. However, coverage and payment options are available. Dr. Klute sees potential value for high-risk patients who understand its limitations and want additional screening beyond standard protocols.
One of the most powerful tools remains readily available to everyone: family history.
“Knowing your family history of cancer can help you and your health care team make smart decisions about cancer screening,” Dr. Klute says.
Our experts at the Fred & Pamela Buffett Cancer Center can help you decide which screening options are best for you.
Call 402.559.5600 to get started.