Increased risk of breast cancer

If you've been diagnosed with atypical hyperplasia, you have an increased risk of developing breast cancer in the future.

Women with atypical hyperplasia have a lifetime risk of breast cancer that is about four times higher than that of women who don't have atypical hyperplasia. The risk of breast cancer is the same for women with atypical ductal hyperplasia and women with atypical lobular hyperplasia.

Recent research has revealed that the risk of breast cancer increases in the years after an atypical hyperplasia diagnosis:

• At 5 years after diagnosis, about 7 percent of women with atypical hyperplasia may develop breast cancer. Put another way, for every 100 women diagnosed with atypical hyperplasia, 7 can be expected to develop breast cancer five years after diagnosis. And 93 will not be diagnosed with breast cancer.
• At 10 years after diagnosis, about 13 percent of women with atypical hyperplasia may develop breast cancer. That means for every 100 women diagnosed with atypical hyperplasia, 13 can be expetected to develop breast cancer 10 years after diagnosis. And 87 will not develop breast cancer.
• At 25 years after diagnosis, about 30 percent of women with atypical hyperplasia may develop breast cancer. Put another way, for every 100 women diagnosed with atypical hyperplasia, 30 can be expected to develop breast cancer 25 years after diagnosis. And 70 will not develop breast cancer.

Being diagnosed with atypical hyperplasia at a younger age may increase the risk of breast cancer even more. For example, women diagnosed with atypical hyperplasia before age 45 seem to have a greater risk of developing breast cancer during their lifetimes.

Discuss your risk of breast cancer with your doctor. Understanding your risk can help you make decisions about breast cancer screening and risk-reducing medications.