Brachytherapy (Partial Breast Radiation) is a form of radiotherapy where a radiation source is placed inside or next to the area requiring treatment. Brachytherapy can be used along or in combination with other therapies such a surgery, radiotherapy, and/or chemotherapy. The treatment entails the exact placement of radiation sources directly at the site of the cancerous tumor. And important element of brachytherapy is that the irradiation is limited to only the areas surrounding the lumpectomy cavity, while sparing areas of healthy breast tissues and underlying structures such as the ribs and lungs. Treatments are delivered twice daily over a 5-day period.
There are different kinds of breast brachytherapy techniques, which vary based on the number and types of catheters used to deliver radiation.
- Interstitial Brachytherapy which involves the insertion of 15-20 catheters in the breast surrounding the lumpectomy cavity. Individual radiation sources are then placed in each catheter.
- Intracavitary Breast Brachytherapy also known as balloon brachytherapy, which uses a single catheter attached to a balloon to deliver radiation. Although the balloon will be kept in the breast for 5 days, the radiation seed only stays inside the balloon for a few minutes.
HOW DOES BRACHYTHERAPY WORK?
Brachytherapy involves placing a radiation source within or close to the cancer. Using brachytherapy, doctors can reduce the radiation exposure to nearby normal tissues that do not need—and may be harmed by—radiation. Brachytherapy is used to treat many types of cancers, such as prostate cancer and gynecologic cancers.
The beauty of breast brachytherapy lies in the laws of physics. Very close to the radioactive seeds, the radiation intensity is extremely high, but just a short distance away (millimeters) this radiation intensity falls off rapidly. This law of physics gives us a therapeutic advantage. If the seeds are precisely positioned in the tissues containing cancer cells, the normal tissues such as lung, heart, ribs, and skin, which are not at risk for having cancer cells can be avoided.
Brachytherapy is regarded as a safe and effective alternative to standard external beam treatment for many patients with breast cancer; overall patient survival with either approach is going to be similar. The primary reason a woman would select breast brachytherapy over standard external beam radiation is time—external beam radiation requires more than six weeks of daily treatment, but breast brachytherapy can be completed in one week.