Risk Of Breast Cancer Recurrence May Be Lower In Moms Who Breastfeed; Tumors Are Less Aggressive, Too
Breastfeeding has been shown to improve a baby’s immune system, lower the risk of developing asthma or allergies, and solidify the relationship between baby and mother. New research shows mom has been reaping the benefits of breastfeeding too, by possibly lowering her breast cancer risk as well as her prognosis if she's diagnosed.
“We’re not looking at the association of breastfeeding on risk of breast cancer but on the [question]: If you breastfed early on and developed breast cancer, what is your prognosis?” said the study’s lead author Marilyn Kwan, a research scientist with Kaiser Permanente’s Division of Research in Oakland, Calif., according to the San Francisco Chronicle.
Kwan and her research team studied more than 1,600 women who had breast cancer, and found those who breastfed had an overall 30 percent lower risk of recurring breast cancer. If a woman breastfed, she also had a 28 percent reduced risk of dying from her breast cancer. The study, published in the Journal of the National Cancer Institute, reaffirms previous findings that found breastfeeding lowers the risk of developing breast cancer in the first place.
"If a woman breastfeeds, she reduces her risk of developing breast cancer by about five percent to 10 percent, although other factors come into play," such as the number of children she gave birth to, Kwan said. "We think this is one of the first [studies] to examine the role of breastfeeding and breast cancer outcomes — prognosis and survival.”
The researchers still have to investigate deeper in order to find the exact cause and effect between breastfeeding and breast cancer. But researchers have found links between breastfeeding and luminal A subtypes of breast cancer — the most common subtypes — including tumors known as estrogen receptor-positive (ER-positive). The American Academy of Pediatrics (AAP) recommends breastfeeding for about six months, during which time mothers not only lower breast cancer risk but also the risk of developing ovarian cancer.
“The message has been getting out about the value to babies of breastfeeding. It really needs to get out about the value to the mom,” Dr. Susan Kutner, a breast surgeon at Kaiser’s San Jose hospital and chairwoman of Kaiser’s Northern California’s Breast Care Task Force, told the Chronicle. She did not participate in the study. “There’s so much we still don’t know. But when breast cells are able to do what they’re supposed to do, they’re fulfilling their function.”
Source: Kwan M. Journal of the National Cancer Institute. 2015.