If you’ve recently been screened for breast cancer, you may have seen the term atypical ductal hyperplasia (ADH) in your results.

Hyperplasia occurs when the number of cells in an organ or a tissue increases. Hyperplasia isn’t cancer, but it may sometimes evolve into cancer.

The ducts in your breast are lined with two layers of cells. In ductal hyperplasia, a person has more than two layers of cells in the breasts.

With usual ductal hyperplasia, these extra cells look normal when viewed under a microscope.

When the extra cells look a little unusual, it’s called ADH. ADH is found in around 5 to 20 percent of all breast biopsies.

There are two types of atypical hyperplasia: ADH and atypical lobular hyperplasia (ALH).

In ADH, extra cells appear on the breast ducts. In ALH, extra cells appear on the milk glands. These glands are also known as lobules.

According to the American Cancer Society (ACS), ADH and ALH occur at similar rates. People with ADH and people with ALH also develop breast cancer at similar rates.

E-cadherin is a type of protein. In some cases, a pathologist will need to perform an E-cadherin test to determine whether you have ADH or ALH.

The presence of E-cadherin is typically associated with ADH, not ALH.

Ductal carcinoma in situ (DCIS) is another term that’s often used during breast cancer screening. It means that there are cancer cells in your ducts, but they haven’t spread to any surrounding tissue.

DCIS is sometimes referred to as stage 0 breast cancer, or precancer, because it’s the earliest form of breast cancer. You can also think of DCIS as a step above ADH in terms of cancer risk.

DCIS requires treatment because there’s no way of knowing if it’ll turn into invasive breast cancer. Treatment usually involves removing the cancerous cells, either through a lumpectomy or mastectomy.

Afterward, you’ll receive radiation, hormonal therapy, or both to help prevent the cancer cells from returning.

A diagnosis of ADH doesn’t mean that you have breast cancer. However, these unusual cells are more likely to turn into cancer. This means that you have a higher risk of developing breast cancer.

According to the ACS, women with ADH or ALH are around four to five times more likely to develop breast cancer than women without breast abnormalities. However, the ACS also notes that most women with atypical hyperplasia don’t develop breast cancer.

Having ADH means you need to see your doctor regularly for breast cancer screenings.

If you’ve been diagnosed with ADH, you have a few options for what to do next.

More frequent screenings

In most cases, your doctor will likely suggest just keeping an eye on the affected breast and coming in for regular screenings to ensure nothing’s changed.

Because there’s no way of knowing if or when someone with ADH will develop cancer, it’s important to make sure you schedule more frequent screenings.

Lifestyle changes

Adopting certain lifestyle changes can also help reduce your risk of developing breast cancer. These include:

If you’re at a higher risk of developing breast cancer, your doctor might suggest medication. A higher risk can be due to previously having cancer or undergoing radiation therapy around your chest at a young age.


The most common types of medication used to lower breast cancer risk are:

These medications can cause serious side effects. Your doctor will only recommend them if you have a substantially higher risk of developing breast cancer.

Receiving an ADH diagnosis doesn’t mean you have breast cancer, but it does increase your risk of developing it. Make sure you follow up with your doctor for regular screenings and tell them about any new symptoms you have.

If you follow up with regular screenings, any signs of breast cancer will likely be caught before they start causing symptoms. Because breast cancer can affect each woman differently, it’s important to keep an eye out for certain warning signs.

These include:

If you notice any of these warning signs, tell your doctor as soon as possible.