mamm interior photo diag MammoSites targeted radiation for breast CADenver’s ABC 7 News reports about MammoSite’s targeted radiation treatment for breast cancer.
The company describes its proprietary, FDA-approved 5-day treatment:

The MammoSite balloon catheter can be placed at the time of lumpectomy or up to 10 weeks post-surgery. Catheter placement is performed either during the surgical procedure under general anesthesia or in an outpatient procedure room under local anesthesia.
The MammoSite catheter is inserted into the surgical cavity through a separate pathway created by a trocar, or via the lumpectomy scar. The balloon end of the catheter is inflated with saline and contrast agent to allow the surrounding tissue to conform to the balloon, the exit site is dressed, and the patient is sent home.
Once the patient has sufficiently recovered from surgery (typically the next day), she is referred to her radiation oncologist for CT of the balloon in the breast and treatment planning.
Radiation therapy is provided on an outpatient basis. During therapy, an Ir192 seed (attached to a high-dose rate [HDR] remote afterloader) is inserted into the inflated balloon for a short duration (typically less than 10 minutes). When used as primary radiation therapy, 2 treatments are administered per day, for 5 days, to deliver the prescribed radiation dose (typically 34 Gy). When used as a boost with external beam radiation, a typical prescription requires treatment for 1-2 days.
After radiation therapy is concluded, the balloon is deflated and the MammoSite catheter is easily removed.

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