Exposing young women and girls under the age of 20 to ionizing radiation can substantially raise the risk of their developing estrogen-negative breast cancer later in life, according to research published in the journal Stem CellsAugust 2013.
“Our results are in agreement with epidemiology studies showing that radiation-induced human breast cancers are more likely to be ER negative than are spontaneous breast cancers,” says Sylvain Costes, a biophysicist with the Lawrence Berkeley National Laboratory.
Epidemiological studies have shown that girls under 20 given radiotherapy treatment for disorders such as Hodgkin’s lymphoma run about the same risk of developing breast cancer in their 40s as women who were born with a BRCA gene mutation. Costes and colleagues concluded that self-renewal of stem cells was the most likely responsible mechanism.
The researchers are now looking for biomarkers that would identify young girls who are at the greatest breast cancer risk from radiation therapy. The results of their study show that the links between ionizing radiation and breast cancer extend beyond DNA damage and mutations.
“Essentially, exposure of the breast to ionizing radiation generates an overall biochemical signal that tells the system something bad happened,” Costes says. “If exposure takes place during puberty, this signal triggers a regenerative response leading to a larger pool of stem cells, thereby increasing the chance of developing ER-negative breast cancers later in life.”
—from a news release from Lawrence Berkeley National Laboratory.
• Read more about TNBC in my book, Surviving Triple-Negative Breast Cancer.