Why use implants for radiation therapy?
Radiation is a very powerful tool in our fight against cancer. It kills cancerous cells, causing tumors to shrink away and die. It can also be dangerous to normal, healthy cells, which is why doctors try to minimize your body’s overall contact with radiation. Implants are a great way to do exactly that.
When you get brachytherapy, a radioactive implant is placed in or immediately next to a cancerous tumor. The implant slowly releases radiation, killing off the cancerous cells. Because the implant is so close to your cancer (or sometimes inside it), this treatment minimizes the amount of radiation needed and protects you from unnecessary harm.
Internal radiation therapy can be combined with external radiation therapy
(which involves shooting a beam of radiation through your body) and chemotherapy
(i.e. injections or pills of powerful, cancer-killing medicines).
Temporary vs. permanent implants
Depending on the type of cancer you have, your overall health, and several other factors, your doctor may opt for either a temporary or permanent implant. A permanent implant, as you might imagine, is left in your body and never removed. Over a period of weeks or months, the implant’s radioactive energy is fully spent and it becomes inert. In short, the implant is designed so it’s perfectly safe to live with.
A temporary implant is different. It’s typically inserted for a short period of time, then removed. This process may be repeated a number of times, depending on the type of treatment you’re getting. You may stay in the hospital during this treatment course, or make daily visits as an outpatient.
High-dose or low-dose radiation?
Another major choice you’ll navigate with your team is between low dose-rate (LDR) and high dose-rate (HDR) brachytherapy.
Low dose-rate therapy takes the ‘slow-and-steady’ approach: Over the course of one or several days, a radioactive implant gives off a small amount of radiation. The implant can then be removed (if it’s a temporary implant) or left in your body as a safely non-radioactive permanent implant.
For most people, LDR is largely painless. The procedure is done under anesthesia (either general or local) and you probably won’t be able to feel the implants after they’re placed. The hospital stay itself may be inconvenient, but you’ll be able to see visitors as long as they observe certain precautions.
HDR, on the other hand, uses temporary implants to deliver short, powerful bursts of radiation. A session lasts just 10-20 minutes, after which the implant is removed to let your body recover. This process is repeated once or twice a day for several days or weeks. Like LDR, the treatment is essentially painless.
The big advantage of HDR is that it’s usually an outpatient procedure (no overnight hospital stays necessary), making it more cost-effective and convenient. You may even be able to drive yourself to and from appointments, depending on the kind of anesthesia you get. Even so, it can be an emotionally and physically challenging experience; be sure to ask your healthcare team about support resources they can offer.
What are these implants like & how are they inserted?
Implants for brachytherapy are sometimes called seeds, ribbons, pellets, capsules, tubes, or wires. They’re generally the same shape as a rice grain, and slightly smaller. They’re made of a radioactive material (like iridium-192 or palladium-103) surrounded by a metal casing. Your healthcare team will use imaging technology (like X-ray or CT scans) to place your implant in exactly the right position—i.e. down to the millimeter—for maximum benefit.
Depending on where your cancer is located, the implants may be placed in a natural body cavity like the uterus or rectum using a special applicator (“intracavitary” treatment). They may also be placed directly in your body tissues (“interstitial” treatment) next to the tumor or even inside it. This technique often uses a catheter, which may remain in your body for several days, so temporary implants can easily be placed and removed.
The good news is that getting an implant is typically painless. Your healthcare team will give you a local anesthetic to block any pain, or a general anesthetic so you’re unconscious during the procedure. In some cases, you may need to lie down in the same position for an extended period of time while the implant does its work. Let your doctor know if this is uncomfortable, and they may be able to prescribe a helpful medication.
After the implant is placed, you shouldn’t be able to feel it at all. (Remember, they’re truly tiny!) You may, however, feel some side effects due to the radiation. These largely depend on the area that’s being treated. For instance, a prostate implant may cause urinary and sexual issues, while an implant in your head / neck area might cause mouth sores and difficulty swallowing. Fatigue is a very common side effect, and may grow over the course of your treatment.
Caring for yourself during & after implant surgery
The most important thing you can do during and after your treatment is to work closely with your healthcare team. Let them know if you have any unusual feelings or symptoms. Even an issue that seems small can spiral into more serious issues, so don’t hesitate to bring up details!
Your team will also give you special instructions to protect your loved ones from radiation while you’re carrying an implant. For instance, if you’re staying in the hospital with a temporary implant, there may be restrictions around who can visit you and how they can interact with you. Or, if you have a permanent implant, you may have to exercise temporary caution around children, pregnant women, and anyone sharing your bed.
Rest assured, these are typically easy guidelines that won’t disrupt your life for very long. Again, listen to your medical team, read any literature they send you home with, and never hesitate to ask questions. Check out our full article about radiation and risks to others
for more information.