Doctors use risk assessment tools to calculate breast cancer risk. Two of the most well-known are the Gail model and the Breast Cancer Surveillance Consortium (BCSC) Risk Calculator.
The Gail model assesses breast cancer risk based on a series of personal health questions that women and their doctors answer together. The questions ask about risk factors such as age, child-bearing history, family history of breast cancer, and breast biopsy results. Some more recent versions of the Gail model ask about alcohol use, menopausal status, and body mass index. The result is a Gail score, which estimates the risk of developing invasive breast cancer in the next 5 years.
The BCSC Risk Calculator is designed to be used by doctors to assess the risk of breast cancer in women:
- who have never been diagnosed with breast cancer or DCIS
- between the ages of 35 and 74
- who have never had breast augmentation
- who have never had a mastectomy
The BCSC Risk Calculator is the only risk assessment tool that includes breast density information when calculating risk.
Researchers have updated the BCSC Risk Calculator to include benign breast disease information to make the tool more accurate.
The study was published online on Aug. 17, 2015 by the Journal of Clinical Oncology. Read the abstract of “Breast Density and Benign Breast Disease: Risk Assessment to Identify Women at High Risk of Breast Cancer.”
Benign breast disease isn’t cancer and isn’t life threatening. Cysts and fatty tumors are examples of benign breast disease. Still, certain types of benign breast disease are known to increase a woman’s risk of breast cancer in the future:
- Excessive growth of normal-looking cells: Doctors call this "proliferative lesions without atypia." In these conditions, cells in the ducts (the pipes that drain the milk out to the nipple) or lobules (the parts of the breast that make milk) are growing faster than normal, but the cells look normal. Doctors call these conditions:
- ductal hyperplasia (without atypia)
- complex fibroadenoma
- sclerosing adenosis
- papilloma or papillomatosis
- radial scar
Being diagnosed with one of these conditions can double your breast cancer risk.
- Excessive growth of abnormal-looking cells: Doctors call this "proliferative lesions with atypia." In these conditions, cells in the ducts or lobules are growing faster than normal and look abnormal. The specific conditions are:
- atypical ductal hyperplasia
- atypical lobular hyperplasia
Being diagnosed with one of these conditions can make your risk of breast cancer 4 to 5 times higher than normal. If you have one or both of these conditions along with a strong family history, your risk can be higher.
- Lobular carcinoma in situ (LCIS): LCIS is abnormal cell growth in the breast lobules. While the word "carcinoma" is in its name, LCIS isn't a true breast cancer. If you've been diagnosed with LCIS, your risk of breast cancer is 7 to 11 times higher than average. LCIS and a strong family history makes your risk even higher.
In the study, the researchers looked at data from 1.1 million women of various races and ethnicities who were ages 35 to 74 and were having regular mammograms. The women had no history of breast cancer; 17% of the women had had a previous breast biopsy.
Half the women were followed for more than 7 years and half the women were followed for less than 7 years.
During follow-up, 17,908 women were diagnosed with invasive breast cancer:
- 16.74% of the women who were NOT diagnosed with breast cancer had been previously diagnosed with benign breast disease
- 25.5% of the women who were diagnosed with breast cancer had been previously diagnosed with benign breast disease
Using the original BCSC model to assess the women’s risk, they found that 9.3% of the women had a 5-year risk of breast cancer of 3% or higher. But when the researchers used the updated model that included benign breast disease history, they found that 27.8% of the women had a 5-year risk of breast cancer of 3% or higher.
"This revised model enables us to more accurately identify those women whose risk may merit use of chemoprevention," said Jeffrey Tice, M.D., of the University of California, San Francisco Division of General Internal Medicine at the Department of Medicine and corresponding author of the paper. "For these women, the benefits of medications that prevent breast cancer generally outweigh the harms. 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."
Chemoprevention means using hormonal therapy medicine, such as tamoxifen, to block the effect of estrogen on breast tissue or reduce the amount of estrogen in the body. Estrogen can make hormone-receptor-positive breast cancers develop and grow.
If you have a history of benign breast disease, it makes sense to talk to your doctor about this study. It also makes sense to sit down with your doctor and use the BCSC calculator to determine your 5-year risk score.
If you have a higher-than-average risk of breast cancer because of benign breast disease history or another risk factor, you and your doctor will develop a screening plan tailored to your unique situation. General recommended screening guidelines include:
- a monthly breast self-exam
- a yearly breast exam by your doctor
- a digital mammogram every year starting at age 40
Your personal screening plan also may include:
Talk to your doctor about developing a specialized program for early detection that meets your individual needs and gives you peace of mind.
It also makes good sense to do all that you can to keep your risk of breast cancer as low as it can be. Some lifestyle choices you may want to consider are:
- maintaining a healthy weight
- exercising every day
- limiting or avoiding alcohol
- eating a healthy diet that’s low in processed foods, sugar, and trans fats
- not smoking
To learn more about breast cancer risk and other options to keep your risk as low as it can be, visit the Breastcancer.org Lower Your Risk section.