Partial Breast Irradiation
(MammoSite)

MammoSite treatment is a part of partial breast irradiation. It is a minimally invasive method of delivering internal radiation therapy following a lumpectomy for breast cancer.

• It places the radiation inside the lumpectomy cavity (the space left when a tumor is removed). The radiation is targeted to the area where cancer is most likely to recur.
• Radiation is delivered from the within the cavity, limiting the amount of radiation to healthy surrounding tissue, thereby reducing the potential for side effects to occur.
• The therapy is given on an outpatient basis and can be completed over 5 to 10 days.

A single, small balloon catheter is placed inside the tumor resective cavity (the space left after the surgeon has removed the tumor).  Once in place, the balloon is inflated with saline (sterile salt water) and a contrast agent, inserted through the applicator. (The contrast agent helps your doctor see the MammoSite balloon more clearly).  The balloon is filled to fit the edges of the cavity. The balloon will remain inflated for the entire time you are receiving radiation therapy. A tiny radioactive seed connected to a machine called an afterloader is inserted into the balloon and delivers the radiation therapy.

After insertion, the area of the breast is cleaned, bandaged and you may return home. Radiation therapy can now begin under the direction of your physician.

No source of radiation remains in your body between treatments or after the final treatment is completed. The tiny radioactive seed is only inserted during your treatment and is removed upon completion of your treatment daily.

Once the final session is completed, the balloon is deflated and is easily removed. In most cases, you will not even require numbing for the removal.

Following treatment, some patients have experienced minor breast-related side effects such as redness, bruising and breast pain. All of these are common side effects of breast surgery and/or radiation therapy. They usually last for only a short time. Some patients also experienced drainage from the insertion site.

While the final analysis is not yet complete - MammoSite is currently being evaluated in clinical trials - patient feedback has been positive. When asked, patients surveyed said they would choose MammoSite treatment again and would recommend that friends or family members explore it as a possible treatment option.

We are pleased to offer this state-of-the-art therapeutic approach to women who qualify, through our radiation oncology department at Washington Adventist Hospital.

Additional Information

For further information on the MammoSite treatment, our radiation oncology program and our entire spectrum of cancer care services, please contact our Cancer Care Navigator at 301-891-5559.