One of the biggest risk factors for breast cancer is a family history of this disease. While it is true that this disease often runs in families, a team of researchers have recently re-examined the role of family background in the onset of breast cancer.

Under the Microscope

This study, published in the The New England Journal of Medicine, offers a more thorough look at this subject. For their study, the authors cast a very wide net; in total, the health histories of nearly 65,000 women were analyzed. Out of this total, approximately half had been previously diagnosed with breast cancer; the remaining half had no history of this disease.

Each participant underwent testing for a dozen genes linked to breast cancer. Using this approach, the research team was able to gain a better understanding of how frequently these genes mutated. Because of this, they were also able to better estimate breast cancer risk among women who possessed such mutations.

Number Crunching

The lead author of the study was Fergus Couch, a pathologist at the prestigious Mayo Clinic. In a press release detailing the report, Couch provided some context regarding his team’s findings. “The risk of developing breast cancer is generally lower for women without a family history of the disease” stated Couch. “When we looked at all women, we found that 30% of breast cancer mutations occurred in women who are not high-risk.”

According to the study authors, the study’s findings were generally consistent for white, black and Hispanic women. Prior to enrolling in the study, the participants had tried without success to get accurate estimates of their breast cancer risk.

The American Cancer Society estimates that over 280,000 women in the US will be diagnosed with breast cancer in 2021 alone. The same organization further estimates that over 43,000 women will succumb to this disease over the same time span.