Researchers from the University of California have refined a national risk model which assesses a woman’s risk of developing breast cancer. These modifications now make it more accurate and reliable. Based on the preliminary data from one million people, there was a 300 percent increase of women with a risk of three percent or higher.
As of 2015 more than 2.8 million American women are reported with a history of breast cancer – including those currently undergoing treatment. Although rates of breast cancer are on the decline, it is estimated that 231,840 new cases of invasive breast cancer will emerge this year. Significant risk factors for breast cancer include gender and age, and roughly 85 percent of cases come from women with no family history of breast cancer.
The current risk model includes density categories including benign results. An early version of the Breast Cancer Surveillance Consortium (BCSC) risk model did not include non-malignant proliferative conditions diagnosed via biopsy. “These include atypical ductal hyperplasia, which raises risk 3.5 to five times higher than those without the condition, and lobular carcinoma in situ, which raises risk to seven to 11 times higher, according to the American Cancer Society.”
Data was examined from 1.1 million racially diverse women, between the ages of 35 and 74, undergoing mammography with no history of breast cancer. After a 6.9 year follow-up nearly 18,000 were diagnosed with invasive breast cancer. This type of breast cancer spreads to healthy tissue outside of the milk ducts.
When women were identified with proliferative findings, researchers uncovered those with a risk of three percent or more increased to 9.3 percent in the first version of BCSC and 27.8 percent in the revised model.
Corresponding author, Jeffrey Tice, said, “This revised model enables us to more accurately identify those women whose risk may merit use of chemoprevention. For these women, the benefits of medications that prevent breast cancer generally outweigh the harms.”
Chemoprevention works to block hormones which fuel tumors as seen in some forms of breast cancer. It can reduce the risk of breast cancer by nearly one-third.
Tice added, “This new information will enable women to work with their physicians to implement an optimal screening and risk reduction plan to reduce their chances of breast cancer.”
The findings were published in the Journal of Clinical Oncology.