Internal radiation is a type of cancer treatment technique where a radioactive implant is put inside the body in or near the tumor. It is also called brachytherapy or seed implantation, and delivers a high dose of radiation directly to the tumor, helping to spare nearby tissues.
With internal radiation therapy, the oncologist implants or inserts temporary or permanent radioactive materials at the site of your cancer.
This radioactive material, known as the seed will slowly release radiation over a few months, and within one year, their radiation completely decays. The seeds can remain safely in place permanently.
Internal radiation therapy uses a radiation source that’s usually sealed in a small holder called an implant and allows a higher dose of radiation in a smaller area that might be possible with external radiation treatment.
Different types of implants may be called the following names:
- balloons, or
No matter which type of implant you use, it is placed very close to or inside the tumor, in your body. This way the radiation harms as few healthy cells as possible.
How Are Implants Placed In The Body?
The implant procedure is usually done in a hospital operating room that is designed to keep the radiation inside the room.
You’ll get anesthesia, where drugs are used to put you into a deep sleep so that you don’t feel pain or where part of your body is numbed.
One or more implants are put into the body cavity or tissue with an applicator. The applicator is usually a metal tube or a plastic tube called a catheter.
Imaging tests like an x-ray, ultrasound, MRI, or CT scan are usually used during the procedure to find the exact place the implant needs to be placed.
Before being implanted, implants are kept in containers that hold the radiation inside so it can’t affect others. The health professionals handling the implants wear special gear that protects them from exposure once the implants are taken out of the container.
Types of Internal Radiation Therapy (Brachytherapy)
There are three types of Internal Radiation Therapy (Brachytherapy):
Low-Dose Rate (LDR) Implants:
In this type of Internal Radiation Therapy, the radiation source stays in place for 1 to 7 days. You are likely to be in the hospital during this treatment time. Once your treatment is finished, your doctor will remove the radiation source and the applicator.
High-Dose Rate (Hdr) Implants:
In this type of Internal Radiation Therapy, the radiation source is left in place for just 10 to 20 minutes at a time and then taken out. You may have treatment twice a day for a couple of days or once a week for 2 to 5 weeks.
During the course of treatment, your catheter or applicator may stay in place, or it may be put in place before each treatment, and your schedule depends on your type of cancer.
You may be in the hospital during this time, or you may choose to make daily trips to the hospital to have the radiation source put in place. As with Low-Dose Rate (LDR) implants, your doctor will remove the catheter or applicator once you have finished treatment.
In permanent implants, after the radiation source is put in place, the catheter is removed, and the implants remain in your body for the rest of your life. But the radiation gets weaker each day, and as time goes on, almost all the radiation will go away.
When the radiation is first put in place, you may need to limit your time around other people and observe some safety measures, like, not spending time with children or pregnant women.
How Long Do Internal Radiation Implants Stay In Place?
The length of time an implant is left in place depends on the type of Internal Radiation Therapy you are getting. While some implants are permanent, others are taken out after a few minutes or days.
The type of implant you get will depend on the kind of cancer, the location of cancer in your body, your general health, and other treatments you may have had.
As for permanent implants, the radioactive materials stop giving off radiation over time, and once the radiation is gone, the implant(s) is no longer active.
Because of its location, they usually stay in place and cause no harm, and there’s no need to take them out.