How DCIS Is Treated

You and your doctor will need to decide whether you should have breast-conserving treatment (where most of the breast is saved) or breast-removing treatment.

The most common treatment for DCIS is breast-conserving treatment, or lumpectomy followed by radiation. The other options—lumpectomy without radiation, or mastectomy—might be either not enough or too much treatment. Each individual situation is different.

Breast-conserving treatment

Most women who have DCIS are able to keep their breast. If the DCIS only appears in one area of the breast, and can be completely removed with clear margins, then breast-conserving treatment is possible. It is usually a very good alternative to mastectomy.

After the DCIS has been removed, radiation is usually given to reduce the risk of cancer coming back in the breast. Read a study about how the two treatments help reduce recurrence. Find out more about radiation after surgery for DCIS.

Surgery:

These surgical procedures may be used to remove the cancer:

• Lumpectomy, also called breast-conserving surgery, removes the entire area of DCIS as well as a rim of normal breast tissue around it. The whole area that contained cancer cells is removed, even when there's no lump present.
• Re-excision removes extra tissue after lumpectomy in order to get clear margins. If there was a very close or positive margin after lumpectomy, your doctor will likely recommend a re-excision.

In certain cases, before surgery, a localizing diagnostic test may be needed. When DCIS can only be seen by a radiology test and cannot be felt, the area of abnormality needs to be "localized." This means that the exact location of the DCIS has to be found before the surgeon can remove it. The localizing needle is placed into the area of concern, and is guided to that area using a radiology technique. That technique is usually mammography or ultrasound. But if the DCIS is only seen by MRI, it might have to be localized under MRI guidance.

Radiation:

After lumpectomy or re-excision, your doctor might discuss several radiation options with you: whole breast radiation, partial breast radiation, or no radiation after lumpectomy.

• Whole breast radiation is given to the entire breast by a machine called a linear accelerator. The area of the breast treated—called the treatment field—is designed to pinpoint the radiation dose. The doctor will avoid or reduce the dose to any surrounding tissues that don't need treatment. Radiation therapy to the whole breast is given five days a week, for about five weeks. Then for another week or two, you will get a radiation boost just to the area where the DCIS had been. Treating the whole breast with radiation after lumpectomy remains the standard of care. It can reduce the risk of the cancer coming back by about half to two thirds. For example, after lumpectomy alone, the risk of the cancer returning is about 30% (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.
• Partial breast radiation is a new form of treatment being offered within a clinical trial. Women can take part in the trial if they have only one area of DCIS that's completely removed with clear margins. This radiation can be delivered in several ways:
  • Using a special device called a MammoSite—a tube with a balloon on the end. The balloon is placed inside the area of the breast where the DCIS had been. Twice a day, for ten treatments, each lasting about five to ten minutes, a radioactive pellet is put inside the balloon to deliver radiation to that part of the breast. At the end of the five-day treatment course, the balloon is removed. This is done as an outpatient procedure (no overnight hospital stay is required).
  • Placing multiple hollow plastic tubes in the area of the breast where the DCIS had been. An appropriate dose of radioactivity is temporarily placed within the tubes. This can be done during a hospital stay or on an outpatient basis, depending on the type of radiation used.
  • Directing multiple small external radiation beams to the area where the DCIS used to be. This is an outpatient procedure.
  • Providing a single dose of "intra-operative" radiation immediately after surgery before you leave the operating room. When this treatment is used, you are still asleep, on the operating table. This is a relatively new type of treatment, so it is not standard care in many hospitals. Also, the results of the final pathology report are not available with this approach.

The options for partial breast radiation vary significantly depending on where you live and get your care. Although 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, it's still considered unproven. No published studies are available yet.

You can participate in a clinical trial in which half the women receive partial breast radiation and the other half get whole breast radiation. The trial is called NSABP B-39 and will soon be available in most cancer centers.

• Having no radiation after lumpectomymay 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 (one 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 extra-close follow-up and observation will be particularly important. This involves visiting your doctor regularly for breast examination and diagnostic 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 useful to seek a second opinion.

Breast-removing treatment

Mastectomy removes the entire breast. Your doctor might recommend mastectomy if the DCIS covers a large area or appears in multiple areas of the breast. Or if you have a significant family history of breast cancer or a proven breast cancer gene abnormality, you might choose mastectomy to guard against your higher risk of developing future breast cancers.