TUESDAY, Sept. 28 (HealthDay News) -- In an effort to improve
the prognosis of patients battling triple-negative breast cancer,
scientists have identified a unique biomarker that may eventually
allow some to receive a more targeted treatment.
Although relatively uncommon, triple negative breast cancer is
notoriously difficult to treat because receptor targeted therapies
don't work. The disease's name refers to breast cancers that test
negative for estrogen receptors, progesterone receptors, and human
epidermal growth factor receptor 2(HER2), all of which fuel most
breast cancer growth.
"Triple-negative breast cancers currently lack therapeutic targets and are managed with conventional chemotherapy," study author Dr. Agnieszka K. Witkiewicz, an associate professor of pathology at Thomas Jefferson University Hospital in Philadelphia, explained in a news release.
In search of new treatment targets, the study's research team
analyzed expression levels of a particular protein called IGF-1R
(insulin-like growth factor) among 97 patients diagnosed with
triple-negative breast cancer. Seventy-three of the patients were
white, and 24 were black.
Witkiewicz and her colleagues found that when it came to IGF-1R,
more is better. High expression of the protein was tied to a lower
risk for lymph node metastasis (spread of the cancer) and had a
borderline association with smaller tumor size. High expression
levels were also linked to longer survival rates among patients
younger than 55.
Among the study patients, about one in four demonstrated IGF-1R
Noting that IGF-IR has already proven to be a successful target
in sarcoma treatment, Witkiewicz said it might ultimately prove to
be a good target for triple-negative breast cancer as well.
"For now, we know that it is there and we know it is a marker of better prognosis," said Witkiewicz. "The next step is to learn if triple-negative breast cancer patients benefit from targeting IGF-1R."
Witkiewicz and her colleagues are slated to present their
findings Tuesday at the American Association for Cancer Research
International Conference on Molecular Diagnostics in Cancer
Therapeutic Development in Denver.
For more on triple-negative breast cancer, visit the
Triple Negative Breast Cancer Foundation.