Atypical Hyperplasia

Time to Read: About 2 minutes

This information will help you understand atypical hyperplasia and how it can affect your risk of getting breast cancer. It also explains what you can do to prevent breast cancer.

About Atypical Hyperplasia

Your breast is made of ducts and lobules. The lobules are small sacs that make breast milk. The ducts are small tubes that carry the breast milk to your nipples. Hyperplasia is a condition where there are more cells than usual in your breast ducts or lobules.  In atypical hyperplasia (ay-TIH-pih-kul LAH-byoo-ler HY-per-PLAY-zhuh) the extra cells look different from normal breast cells.

Types of Atypical Hyperplasia

There are 2 main types of atypical hyperplasia. They are atypical ductal hyperplasia (ADH) and atypical lobular hyperplasia (ALH).

Atypical ductal hyperplasia (ADH)

In ADH, new cells look like the cells that grow in your breast ducts. ADH isn’t cancer, but it may raise your risk of getting breast cancer in the future.

A needle biopsy (a procedure to take a small sample of tissue) can show if you have ADH. You may need surgery to be sure that you don’t also have breast cancer. If you don’t have cancer, talk with your healthcare provider about the screening guidelines you should follow. Talk about how you can lower your risk of getting breast cancer later on. You can also learn more about MSK’s breast cancer screening guidelines.

Atypical lobular hyperplasia (ALH)

In ALH, new cells look like the cells that grow in your breast lobules. ALH is linked to a higher risk of getting breast cancer.

A needle biopsy (a procedure to take a small sample of tissue) can show if you have ALH. If they find ALK, surgery isn’t always needed. You and your healthcare provider will decide if surgery is right for you.

Breast Cancer Screening

Because of the increased breast cancer risk, people with either type of atypical hyperplasia should get regular breast exams and breast imaging tests. You and your healthcare provider will decide what type of breast imaging is best for you, based on your personal history. MSK recommends you have a physical exam with a breast specialist every 6 to 12 months. You also should have breast imaging every year.

Lowering Your Breast Cancer Risk

Medications

Taking certain medications can help lower your risk of getting breast cancer. Studies show that the following medications may lower your risk of breast cancer by more than half. Talk with your healthcare provider about starting medication so you can discuss what’s best for you.

Tamoxifen and raloxifene

Tamoxifen (Nolvadex®, Soltamox®) and raloxifene (Evista®) are medications that lower your risk for breast cancer. They block the effects of estrogen, which can make some breast tumors grow. Estrogen is a natural hormone your body makes. These medications only lower your risk of getting a certain type of breast cancer. It’s called estrogen receptor-positive breast cancer, which is the most common type. They will not lower your risk of getting estrogen receptor-negative cancers.

You can only take raloxifene if you have gone through menopause (permanent end of your menstrual cycle). You can take tamoxifen before or after menopause.

Aromatase inhibitors

Aromatase inhibitors are medications that stop an enzyme called aromatase from changing other hormones into estrogen. One of these medications, exemestane (Aromasin®), has been shown to lower the risk of breast cancer in people with atypical hyperplasia. You should only take these medications if you have gone through menopause.

Prophylactic mastectomy

Some people may choose to have their breasts removed to prevent breast cancer. This is called a bilateral prophylactic (PRO-fih-LAK-tik) mastectomy. This surgery is sometimes used to lower the risk of breast cancer in people with ADH or ALH.

Lifestyle changes

There are also lifestyle changes you can make to lower your breast cancer risk if you have LCIS. You can talk with your healthcare provider about these lifestyle changes.

Last Updated

Friday, January 25, 2019

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