Brachytherapy or Internal Radiation
Internal radiation, called brachytherapy by doctors, can be an option for certain women after lumpectomy. The size and location of the cancer may limit who is a good candidate for brachytherapy.
According to guidelines released by the American Brachytherapy Society, appropriate candidates for brachytherapy are women age 45 and older diagnosed with DCIS or early-stage invasive breast cancer removed by lumpectomy that:
is hormone-receptor-positive or hormone-receptor-negative
is 3 cm or smaller in size
is node-negative (no cancer was found in the lymph nodes)
is not in the lymphovascular system
has negative or clear margins, meaning no cancer cells were found in the rim of healthy tissue removed with the cancer
Brachytherapy is a way to deliver accelerated partial-breast radiation. Accelerated partial-breast radiation gives a larger dose of radiation over a shorter period of time to only the part of the breast where the cancer was, rather than the entire breast.
Brachytherapy methods typically use small pieces of radioactive material, called seeds, which are placed in the area around where the cancer was. The seeds emit radiation into the surrounding tissue. The area that's very close to the site of the original cancer is the area that is at highest risk of recurrence.
Brachytherapy is most commonly delivered using multiple small tubes or catheters (called multi-catheter brachytherapy) or using a balloon-catheter or other device (called balloon-catheter or applicator brachytherapy).
In multi-catheter brachytherapy, tiny tubes (catheters) are sewn under the skin in the area where the cancer was. The ends of the tubes stick out through little holes in the skin. Tiny stitches or a grid hold the tubes in place.
Based on a treatment plan designed for you, a machine will place a radioactive seed into the tubes to deliver the radiation. Special precautions are taken to keep you and those around you safe from the radiation. Once the treatment is done, the stitches and tubes are removed along with the seed. Multi-catheter brachytherapy treatment is usually given as an outpatient procedure over 5 days, with two treatments each day.
Planning for multi-catheter brachytherapy involves meeting with your radiation oncologist and possibly having X-rays or other imaging done to plan exactly where the radiation will be delivered.
After the planning is complete, a member of your radiation team will place small tubes, called catheters, under the skin in the area where the cancer was and will sew the tubes into place or they will be in a grid. The ends of the catheters will stick out through small holes in the skin. Small stitches hold the catheters in place.
Treatments are usually performed as outpatient procedures using high dose radiation twice daily for 5 days. Each treatment will last about an hour, and you will be able to leave the hospital after each one. During the treatment, a machine will move a small piece of radioactive material, called a radioactive seed, into the catheters. The seed will be left in for up to 10 minutes. After each treatment is finished, the seed is removed. You do not remain radioactive after the seed is removed. Once all treatments are complete, the catheters and stitches are removed.
If low-dose radiation is used, the treatment can be delivered over many hours or a few days. You have to stay in the hospital throughout the treatment because there will be radioactivity inside you. The radioactive seeds slowly deliver the radiation to the tissues surrounding the catheters. Special precautions are taken to keep you and those around you safe from the radiation. Once the treatment is complete, the radioactive seeds, stitches, and catheters are removed. Then you can go home.
Balloon catheter or applicator brachytherapy
In balloon catheter or applicator brachytherapy, a special tube with a balloon or a different kind of device on the end is used. With careful planning, the balloon or applicator is placed into the area where the cancer was. The tube comes out through a little hole in the skin. The balloon or applicator can be inserted in an operating room or in a surgeon's office and stays in place for about a week and a half.
During each treatment, a machine places a radioactive seed into the balloon or applicator for about 5 to 10 minutes — just long enough to deliver the prescribed dose of radiation. A total of 10 treatments are usually given over 5 days. That means two treatments per day, about 6 hours apart. When the final treatment is done, the balloon is removed through the small hole in the skin.
In balloon catheter or applicator brachytherapy, the applicator has a balloon or other device on one end. The applicator is placed in the area of the breast where the lumpectomy was done and can be placed either during the lumpectomy surgery or during a short procedure in a surgeon’s office soon after the lumpectomy. The other end of the applicator comes out through a little hole in the skin.
Balloon catheter or applicator brachytherapy is usually given twice a day for 5 days. During each treatment, a machine places a radioactive seed into the balloon or applicator for up to 10 minutes. The seed is then removed and you are free to leave the treatment center. You do not remain radioactive after the seeds are removed. When the final treatment is done, the balloon is removed through the hole in the skin.
Brachytherapy can also be used for giving a boost dose at the end of an external whole breast radiation treatment regimen. A boost dose is a supplemental dose of radiation given towards the end of your treatment to target the area around where the tumor was. The boost dose is given in the same manner as regular brachytherapy, using either small tubes, a balloon catheter, or an applicator. However, radiation boosts are usually given with external beam radiation rather than brachytherapy nowadays.
Benefits and drawbacks of brachytherapy
Brachytherapy was developed to reduce the risk of breast cancer recurrence while shortening the amount of time it takes to get radiation treatment. Brachytherapy may also limit the dose of radiation (and associated side effects) to the surrounding normal tissue including the heart and lungs.
Compared to external radiation, brachytherapy has several benefits:
The treatment time can be shorter — 5 days vs. 5 days to 4 weeks with external radiation.
Radiation is given only to the area where the cancer is most likely to come back. Less of your body receives radiation, so there may be fewer side effects.
Results from studies done so far show a very low risk of recurrence after internal radiation.
But there are some unknowns involved with brachytherapy that should be discussed with your doctor as you make your treatment decisions:
Brachytherapy is only used after lumpectomy. It is not used after mastectomy.
Long-term outcomes data with balloon or applicator brachytherapy are limited.
— Last updated on December 16, 2021, 9:58 PM