Researchers find circulating tumor cells in long-term cancer survivors

Researchers at UT Southwestern Medical Center at Dallas have shown that some long-term breast-cancer survivors may have innate mechanisms to keep breast cancer at bay.

Their findings, published in the December issue of Clinical Cancer Research and available online, show that one-third of the longtime disease-free patients in the study had circulating tumor cells (CTCs). The presence of CTCs is often associated with a higher risk of recurrence if they are found soon after a mastectomy. The UT Southwestern discovery that CTCs can be found in patients up to 20 years after mastectomy is notable because these patients have a very low risk of recurrence. After 20 years, the risk of recurrence rises to 20 percent of survivors, and scientists are still unsure why.

“Dormancy is a mysterious phenomenon that occurs in certain types of cancer,” said Dr. Jonathan Uhr, lead author of the study and professor in the Cancer Immunobiology Center and of microbiology and internal medicine. “The term refers to a recurrence of cancer long after the tumor has been removed.”

Based on his previous data gathered from mouse models of cancer dormancy, Dr. Uhr and colleagues used a stringent and sensitive set of tests to identify CTCs in women who had mastectomies and had been clinically cancer-free for at least seven years. The investigators collected blood from 36 study participants. Of those, 13 breast-cancer survivors had CTCs, but the number of CTCs was low and remained low. Because CTCs are short-lived, they must be constantly replenished, possibly from many tiny tumors somewhere in the body.

Dr. Uhr said that there appears to be a precise balance between tumor cell replication and cell death. Those who stay healthy may have developed a way of keeping the size of the tumor cell population in check, making breast cancer a chronic illness in these patients, he said.

The next step, Dr. Uhr said, is to investigate the mechanisms for how the body and the cancer cells peacefully coexist. Such studies could reveal new ways to control cancer. “It is also important to determine what changes are responsible for relapse,” he said. “If patients at risk for impending relapse can be identified, it may be possible to prevent recurrence with appropriate therapy.”

Other UT Southwestern contributors to this study included Drs. Debasish Tripathy, Eugene Frenkel and Barbara Haley, all professors of internal medicine; Dr. James Huth, chairman of surgical oncology; Dr. Marilyn Leitch, professor of surgical oncology; Dr. David Euhus, associate professor of surgical oncology; Drs. Songdong Meng and Jianqiang Wang, postdoctoral researchers in the Cancer Immunobiology Center; and Nancy Lane, research scientist in the Cancer Immunobiology Center.

Media Contact

Megha Satyanarayana EurekAlert!

More Information:

http://www.utsouthwestern.edu/

All latest news from the category: Health and Medicine

This subject area encompasses research and studies in the field of human medicine.

Among the wide-ranging list of topics covered here are anesthesiology, anatomy, surgery, human genetics, hygiene and environmental medicine, internal medicine, neurology, pharmacology, physiology, urology and dental medicine.

Back to home

Comments (0)

Write a comment

Newest articles

Lighting up the future

New multidisciplinary research from the University of St Andrews could lead to more efficient televisions, computer screens and lighting. Researchers at the Organic Semiconductor Centre in the School of Physics and…

Researchers crack sugarcane’s complex genetic code

Sweet success: Scientists created a highly accurate reference genome for one of the most important modern crops and found a rare example of how genes confer disease resistance in plants….

Evolution of the most powerful ocean current on Earth

The Antarctic Circumpolar Current plays an important part in global overturning circulation, the exchange of heat and CO2 between the ocean and atmosphere, and the stability of Antarctica’s ice sheets….

Partners & Sponsors