Standard treatment options for DCIS include:
- Lumpectomy followed by radiation therapy: This is the most common treatment for DCIS. Lumpectomy is sometimes called breast-conserving treatment because most of the breast is saved.
- Mastectomy: Mastectomy, or removal of the breast, is recommended in some cases.
- Lumpectomy alone
- Hormonal therapy after surgery: These treatments, which block or lower the amount of estrogen in the body, are typically used if the DCIS tests positive for hormone receptors.
Chemotherapy, a form of treatment that sends anti-cancer medications throughout the body, is generally not needed for DCIS. DCIS is non-invasive and remains within the breast duct, so there is no need to treat cancer cells that might have traveled to other areas of the body.
Each individual situation is different. You and your doctor will decide what treatment is best for your situation. If the DCIS is large, high-grade, and comedo type, for example, it is likely to be more aggressive, and your doctor may recommend more extensive treatment. The same holds true if you are under age 40, since younger age may increase the risk of recurrence.
Lumpectomy followed by radiation therapy
Most people with DCIS have a lumpectomy followed by radiation therapy. This is usually a very good option if the DCIS only appears in one area of the breast and can be completely removed with clear margins of healthy tissue. A clear margin is a rim of healthy tissue around the tumor that is completely free of cancer cells. How wide do these margins need to be? Doctors are still debating the answer, but a width of 2 to 3 mm is common.
Lumpectomy, and in some cases a second procedure called re-excision lumpectomy, is used to completely remove the cancer.
- Lumpectomy removes the entire area of DCIS as well as a margin of normal, healthy breast tissue around it. The whole area that contained cancer cells is removed, even when there's no lump present.
- Re-excision lumpectomy is a second surgery that may be necessary after lumpectomy to remove extra tissue in order to ensure that there is a clear margin of healthy tissue around the tumor. If your doctor finds that the margins of healthy tissue taken were too narrow, or there is even some cancer present in the margins, a re-excision may be recommended.
If the DCIS has been removed with lumpectomy, radiation is usually given to reduce the risk of cancer returning. Your doctor may discuss a couple of radiation options with you:
- External radiation is given to the entire breast by a machine called a linear accelerator. Radiation treatment is usually given as daily treatments 5 days per week over 5 to 7 weeks. Treating the whole breast with radiation after lumpectomy remains the standard of care. In cases of DCIS, radiation therapy can reduce the risk of the cancer coming back by about 60%. For example, after lumpectomy alone, the risk of the cancer returning is about 30%, although it may be lower or higher, depending on the situation. Radiation can reduce that risk to 10% or less for a return of invasive cancer and to about 15% for a return of DCIS.
- Internal partial-breast irradiation is a form of treatment in which radioactive materials such as seeds or pellets are temporarily placed in the breast. There’s a lot of interest in partial breast radiation for DCIS, because treatment is shorter and side effects occur in a smaller part of the breast. However, its effectiveness is still being studied.
External partial-breast irradiation is a method of therapy that zeroes in on the area around where the cancer was. This area is at highest risk of recurrence. Partial-breast radiation takes only 5 to 10 days for treatment, versus 5 to 7 weeks for whole breast radiation. Researchers are studying partial-breast radiation for use after lumpectomy to see how the benefits compare to the current standard of radiation to the whole breast.
Women may be able to take part in a clinical trial studying external partial-breast radiation if they have only one area of DCIS that's completely removed with clear margins. The trial is called NSABP B-39 and is available in many cancer centers. Ask your doctor for more information about this trial if you feel you might qualify. You can also visit our Clinical Trials section to learn more about how trials work.
Mastectomy removes the entire breast. Although many cases of DCIS are treated with lumpectomy, your doctor might recommend mastectomy if the DCIS covers a large area or appears in multiple areas of the breast. In most DCIS cases requiring mastectomy, simple or total mastectomy (removal of breast tissue but no lymph nodes) is performed. Radiation is usually not necessary after mastectomy for DCIS.
Some situations in which doctors might recommend mastectomy for DCIS:
- There is a large area of DCIS.
- There is more than one area of DCIS in the breast (called multifocal disease).
- A biopsy shows DCIS cells near or at the margin of healthy tissue, in which case taking more tissue to achieve acceptable margins would result in poor cosmetic outcome.
- If you have a strong family history of breast cancer, or you have tested positive for a gene mutation that increases breast cancer risk, you might choose mastectomy to guard against your higher risk of developing future breast cancers.
Not being a candidate for radiation therapy: Most of the time, people treated with lumpectomy for DCIS also receive radiation therapy. If you’ve had previous radiation to the chest or breast, if you have a condition that makes you more sensitive to radiation, or if you are in your first trimester of pregnancy when diagnosed, you might not be eligible to receive radiation therapy.
If you are thinking about mastectomy for DCIS, you may also want to consider breast reconstruction options as you’re planning your surgery.
Checking the lymph nodes for any signs of cancer spread is not a standard part of treatment for DCIS, although it does happen in some cases. Early research shows that in some DCIS cases, there may be a benefit in having sentinel node biopsy (removing only the first 1 to 3 nodes closest to the cancer). Some factors that may lead to sentinel or underarm lymph node biopsy:
- The breast has widespread areas of DCIS.
- There is a significant amount of high-grade DCIS in the breast.
- microinvasion (small amounts of cancer have spread beyond the milk duct)
- Diagnosis of DCIS happened at a young age (under 40).
Having no radiation after lumpectomy may be an option for you if your risk of recurrence is very low after lumpectomy alone. In this situation, adding radiation may offer only minimal benefit. This may be true if:
- You have a very small area of low-grade DCIS (just a few millimeters) that was completely removed with wide negative margins of resection (1 centimeter or more).
- You are over 70 with other active medical problems that are more serious than DCIS. Radiation to be sure the DCIS is completely gone may be a relatively low priority.
If you decide on lumpectomy only, then close follow-up and observation will be particularly important. This involves visiting your doctor regularly for breast examination and imaging studies such as mammograms, ultrasound, or MRIs.
The decision not to have radiation treatment must be considered very carefully with your medical team. It can also be helpful to seek a second opinion.
People with DCIS have a slightly higher risk of developing another breast cancer in the future than people who have not had DCIS. Adding hormonal therapy to surgery and radiation for DCIS can reduce this risk if the tumor tests positive for hormone receptors.
Not all hospitals automatically test DCIS for hormone receptors, so make sure to ask your doctor to have the DCIS tested this way.
- Tamoxifen (brand name: Nolvadex) can be used for early-stage cancers that are hormone-receptor-positive, instead of or following radiation treatment after lumpectomy. Tamoxifen "pretends" to be estrogen and attaches to the receptors on the breast cancer cells, taking the place of real estrogen. As a result, the cells don't receive the signal to grow. People with hormone-receptor-positive cancer who take tamoxifen can lower their risk of having an invasive cancer or a non-invasive cancer come back.
- Aromatase inhibitors such as Arimidex (chemical name: anastrozole), Femara (chemical name: letrozole), and Aromasin (chemical name: exemestane) are being studied in clinical trials to find out if they are effective in reducing the risk of recurrence in people with DCIS. These medications reduce the amount of estrogen produced in a woman's body after she goes through menopause. The main sources of the hormone for those women are the adrenal glands and fat tissue, not the ovaries.
Before surgery: Finding the exact location of DCIS
Before surgery, you may need to have a diagnostic test to "localize" the tumor. When DCIS can only be seen by a mammogram or ultrasound and cannot be felt, the exact location of the tumor has to be pinpointed before the surgeon can remove it. A localizing needle is placed near the area of concern and then guided to the cancer with the aid of mammogram or ultrasound. If the DCIS is only seen by MRI (magnetic resonance imaging), it may need to be localized with the help of an MRI machine.