Ductal carcinoma in situ (DCIS)

Overview

Ductal carcinoma in situ is a very early form of breast cancer. In ductal carcinoma in situ, the cancer cells are confined inside a milk duct in the breast. The cancer cells haven't spread into the breast tissue. Ductal carcinoma in situ is often shortened to DCIS. It's sometimes called noninvasive, preinvasive or stage 0 breast cancer.

DCIS is usually found during a mammogram done as part of breast cancer screening or to investigate a breast lump. DCIS has a low risk of spreading and becoming life-threatening. However, it does require an evaluation and a consideration of treatment options.

Treatment for DCIS often involves surgery. Other treatments may combine surgery with radiation therapy or hormone therapy.

Symptoms

Ductal carcinoma in situ doesn't typically cause symptoms. This early form of breast cancer also is called DCIS.

DCIS can sometimes cause symptoms such as:

• A breast lump.
• Bloody nipple discharge.

DCIS is usually found on a mammogram. It appears as tiny flecks of calcium in the breast tissue. These are calcium deposits, often referred to as calcifications.

When to see a doctor

Make an appointment with your doctor or other healthcare professional if you notice a change in your breasts. Changes to look for may include a lump, an area of puckered or otherwise unusual skin, a thickened region under the skin, and nipple discharge.

Ask your healthcare professional when you should consider breast cancer screening and how often it should be repeated. Most healthcare professionals recommend considering routine breast cancer screening beginning in your 40s.

Causes

It's not clear what causes ductal carcinoma in situ, also called DCIS.

This early form of breast cancer happens when cells inside a breast duct develop changes in their DNA. A cell's DNA holds the instructions that tell the cell what to do. In healthy cells, the DNA gives instructions to grow and multiply at a set rate. The instructions tell the cells to die at a set time. In cancer cells, the DNA changes give different instructions. The changes tell the cancer cells to make many more cells quickly. Cancer cells can keep living when healthy cells would die. This causes too many cells.

In DCIS, the cancer cells don't yet have the ability to break out of the breast duct and spread into the breast tissue.

Healthcare professionals don't know exactly what causes the changes in the cells that leads to DCIS. Factors that may play a part include lifestyle, environment and DNA changes that run in families.

Risk factors

Several factors may increase the risk of ductal carcinoma in situ, also called DCIS. DCIS is an early form of breast cancer. Risk factors for breast cancer may include:

• A family history of breast cancer. If a parent, sibling or child had breast cancer, your risk of breast cancer is increased. The risk is higher if your family has a history of getting breast cancer at a young age. The risk also is higher if you have multiple family members with breast cancer. Still, most people diagnosed with breast cancer don't have a family history of the disease.
• A personal history of breast cancer. If you've had cancer in one breast, you have an increased risk of getting cancer in the other breast.
• A personal history of breast conditions. Certain breast conditions are a sign of a higher risk of breast cancer. These conditions include lobular carcinoma in situ, also called LCIS, and atypical hyperplasia of the breast. If you've had a breast biopsy that found one of these conditions, you have an increased risk of breast cancer.
• Beginning your period at a younger age. Beginning your period before age 12 increases the risk of breast cancer.
• Beginning menopause at an older age. Beginning menopause after age 55 increases the risk of breast cancer.
• Being female. Women are much more likely than men are to get breast cancer. Everyone is born with some breast tissue, so anyone can get breast cancer.
• Dense breast tissue. Breast tissue is made up of fatty tissue and dense tissue. Dense tissue is made of milk glands, milk ducts and fibrous tissue. If you have dense breasts, you have more dense tissue than fatty tissue in your breasts. Having dense breasts can make it harder to detect breast cancer on a mammogram. If a mammogram showed that you have dense breasts, your risk of breast cancer is increased. Talk with your healthcare team about other tests you might have in addition to mammograms to look for breast cancer.
• Drinking alcohol. Drinking alcohol increases the risk of breast cancer.
• Having your first child at an older age. Giving birth to your first child after age 30 may increase the risk of breast cancer.
• Having never been pregnant. Having been pregnant one or more times lowers the risk of breast cancer. Never having been pregnant increases the risk.
• Increasing age. The risk of breast cancer goes up as you get older.
• Inherited DNA changes that increase cancer risk. Certain DNA changes that increase the risk of breast cancer can be passed from parents to children. The most well-known changes are called BRCA1 and BRCA2. These changes can greatly increase your risk of breast cancer and other cancers, but not everyone with these DNA changes gets cancer.
• Menopausal hormone therapy. Taking certain hormone therapy medicines to control the symptoms of menopause may increase the risk of breast cancer. The risk is linked to hormone therapy medicines that combine estrogen and progesterone. The risk goes down when you stop taking these medicines.
• Obesity. People with obesity have an increased risk of breast cancer.
• Radiation exposure. If you received radiation treatments to your chest as a child or young adult, your risk of breast cancer is higher.

Prevention

Making changes in your daily life may help lower your risk of ductal carcinoma in situ. This early form of breast cancer also is called DCIS. To lower your risk of breast cancer, try to:

Ask about breast cancer screening

Talk with your doctor or other healthcare professional about when to begin breast cancer screening. Ask about the benefits and risks of screening. Together, you can decide what breast cancer screening tests are right for you.

Become familiar with your breasts through breast self-exam for breast awareness

You may choose to become familiar with your breasts by occasionally inspecting them during a breast self-exam for breast awareness. If you find a new change, lumps or other unusual signs in your breasts, tell a healthcare professional right away.

Breast awareness can't prevent breast cancer. But it may help you to better understand the look and feel of your breasts. This might make it more likely that you'll notice if something changes.

Living with ductal carcinoma in situ (DCIS)?

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