← Breastcancer.org

Certain Risk Factors Affect Different Types of Breast Cancer in Different Ways

Sign in to receive recommendations (Learn more)

A study found that certain risk factors for breast cancer:

  • getting older
  • being overweight
  • drinking alcohol
  • using hormone replacement therapy (HRT)

affect the risk of specific types of breast cancer in different ways.

The researchers analyzed the records of more than 2,500 women in two studies:

  • LACE (Life After Cancer Epidemiology)
  • The Pathways Study
The researchers looked at how the risk factors affected four types of breast cancer:
  • hormone-receptor-positive (either estrogen- and/or progesterone-positive), HER2-negative breast cancer, called luminal A breast cancer
  • hormone-receptor-positive (either estrogen- and/or progesterone-positive), HER2-positive breast cancer, called luminal B breast cancer
  • hormone-receptor-negative (either estrogen- and/or progesterone-negative), HER2-negative breast cancer, called triple-negative breast cancer
  • hormone-receptor-negative (either estrogen- and/or progesterone-negative), HER2-positive breast cancer, called HER2 over-expressing breast cancer

Hormone-receptor-positive, HER2-negative breast cancer (luminal A) is the most common type of breast cancer and tends to have a better prognosis than the other three types studied. Women diagnosed with hormone-receptor-positive, HER2-negative breast cancer are more likely to drink alcohol, use HRT, and be older compared to women diagnosed with the other types.

Hormone-receptor-positive, HER2-positive breast cancer (luminal B) tends to have a worse prognosis than hormone-receptor-positive, HER2-negative breast cancer but a better prognosis than the other two types. Women diagnosed with hormone-receptor-positive, HER2-positive breast cancer are likely to be younger, but less likely to drink alcohol or use HRT compared to women diagnosed with the other types.

Hormone-receptor-negative, HER2-negative breast cancer (triple-negative) tends to have a worse prognosis than the other types studied. Women diagnosed with triple-negative breast cancer are more likely to be younger, overweight, and African American compared to women diagnosed with the other types.

Hormone-receptor-negative, HER2-positive breast cancer (HER2 over-expressing) tends to have a worse prognosis than breast cancer that is hormone-receptor-positive. Women diagnosed with hormone-receptor-negative, HER2-positive breast cancer are likely to be younger and Hispanic or Asian, and less likely to use HRT compared to women diagnosed with the other types.

Understanding the ways specific risk factors can affect the risk of different types of breast cancer may help create programs targeted at specific groups of women at highest risk. For example, the results of this study suggest that a good way to lower the risk of triple-negative breast cancer would be to focus on young, overweight African American women because those three factors are linked to a higher risk of triple-negative breast cancer.

Visit the Breastcancer.org Lower Your Risk section to learn more about breast cancer risk and steps you can take to make sure your risk is as low as it can be.

Evergreen-donate
Back to Top