Mammosite

A new alternative for some women who have breast conserving surgery is partial-breast irradiation. It works by delivering radiation from inside the lumpectomy cavity (the space left after the tumor is removed) directly to the tissue surrounding the cavity where the cancer is most likely to recur.

The MammoSite® RTS treatment is a 2-stage process: balloon placement and radiation delivery. After the surgeon performs the lumpectomy, an uninflated MammoSite® RTS balloon connected to a catheter, is placed inside the cavity where the tumor was. A portion of the catheter remains outside of your breast. Once in place, the balloon is inflated with a sterile salt water solution to fit snugly into your lumpectomy cavity. The balloon remains inflated for the entire time you are receiving radiation therapy (usually 5 days). After the MammoSite® RTS is in place, that area of the breast is cleaned and bandaged and you may go home.

MammoSite® RTS treatment is given under the direction of a radiation oncologist who will determine the amount of radiation needed. It is delivered on an outpatient basis twice a day for 5 days. During radiation therapy, the portion of the catheter that remains outside your breast will be connected to a computer-controlled machine. A tiny radioactive seed will travel from the machine, through the catheter and into the inflated balloon inside your breast. The seed will remain in the balloon and deliver radiation for about 10 minutes. The seed is then withdrawn back into the machine. The machine is disconnected from the Mammosite® RTS catheter and your treatment session is complete. No radiation will remain in your breast between treatments or after your final treatment. Usually on the same day as your final radiation treatment, the MammoSite® RTS balloon will be deflated and easily removed.