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Dr. Mike Smith (Host): Brachytherapy is a form of radiotherapy where a sealed radiation source is placed inside or next to the area requiring treatment. Welcome to the GW Medical Faculty Associates Podcast. I’m Dr. Mike Smith and today’s topic: What to Expect from Brachytherapy Treatment. My guest is Dr. Yuan Rao. Dr. Rao is Assistant Professor of Radiation Oncology at the George Washington University School of Medicine and Health Sciences. Dr. Rao, welcome to the show.

Yuan James Rao, MD (Guest): Hello, thank you for inviting me on to the show.

Host: So, why don’t we start with a nice simple question. Maybe you could explain to us exactly what is brachytherapy.

Dr. Rao: Well the term brachytherapy stands for close treatment. So, for normal types of radiation, as in external beam radiation; the radiation is generated by a machine that goes through the body to reach the tumor. However, this treats a lot of normal tissue that’s in the way. Brachytherapy as opposed to external radiation allows us to place the radiation sources very close to or sometimes even inside of the tumor which allows us to deliver curative treatments to the tumor while minimizing the radiation exposure to the surrounding tissue. And this has a possibility of achieving the same rate of curative success while significantly decreasing the toxicity of radiation.

Host: What type of cancers is brachytherapy used in?

Dr. Rao: So, the brachytherapy is most commonly used for cancers of the pelvis. For instance prostate cancer is a very common cancer that’s treated with brachytherapy. One thing that maybe used is something called seed implants where small radioactive seeds are placed inside of the prostate under ultrasound guidance. An upcoming type of brachytherapy for prostate cancer is something called high dose rate brachytherapy which will be available at George Washington University. This is where we will place some small catheters rather than seeds into the prostate and then the radiation source will go inside of those catheters and then outside of patient. So, that once the treatment is completed; there is nothing that’s radioactive left inside of the patient which could cause additional side effects.

Another type of brachytherapy application is for GYN or gynecological malignancies. For instance after a woman receives a hysterectomy for endometrial cancer, there is sometimes a need to deliver radiation and this radiation can be delivered either as a course of external radiation or as a course of brachytherapy. And obviously, if the radiation can be delivered as brachytherapy; it is much more convenient for the patient, usually delivered over the course of about six treatments rather than over the course of about five weeks and the toxicity is expected to be much less because we are treating much less normal tissue.

And then finally, there are some other types of tumors that can be treated with brachytherapy as well. One of these includes breast cancer. So, certain kinds of breast cancer where the tumor is limited to a small portion of the breast; can be treated with a focal treatment to the resection cavity rather than to the entire breast. And this may also decrease toxicity of breast cancer treatment.

Host: So, Dr. Rao, how do you decide – a couple questions for you now. So, how do you decide if traditional radiation is the way to go versus brachytherapy and then within that answer, I guess you could also get into how common is brachytherapy actually done?

Dr. Rao: Ah, that’s a very good question. So, I’ll use prostate cancer as a good example of this. So, for a prostate cancer, brachytherapy can be used for patients with what is called favorable or intermediate risk disease. This is prostate cancer that’s limited to the prostate and has not go outside of the capsule of the prostate or gone to the lymph nodes or other parts of the body. When the prostate cancer is limited in such a manner; the patient actually has a choice between receiving surgery, receiving external beam radiation therapy or receiving brachytherapy.

And in my opinion, the brachytherapy is actually a very good balance between convenience and toxicity. For instance, surgery may have the toxicities associated with an operation including blood loss and radiation – external radiation treatment is somewhat inconvenient in that patients sometimes have to come for eight or nine weeks of daily radiation treatment.

Brachytherapy is a modality in the middle where they still receive a curative treatment but that is much more convenient compared to external radiation and may have fewer toxicities compared to surgery. This is usually the situation in other types of cancer as well. When there are many good treatments, so brachytherapy is a good balance between the types of treatments that are available.

However, there are certain types of malignancies where the brachytherapy is critical. For instance, in cervix cancer and other GYN malignancies, brachytherapy is a critical part of the curative treatment of those cancers and is actually associated with improved survival and improved local control for these types of tumors.

Host: So, you’ve mentioned a couple of times now that obviously, the brachytherapy is more convenient, but there’s also less toxicity and that’s good news to hear. But if somebody is going to undergo brachytherapy; what are some of the side effects that they might experience?

Dr. Rao: That’s a good question. So, for prostate cancer brachytherapy; the primary side effect is associated with swelling from placement of the catheters or the seeds. It is a minor surgical procedure so the patient will be asleep or have some sedation and under ultrasound guidance, these markers, seeds or catheters will be placed inside of the prostate. When the patient wakes up, there will some discomfort and some urgency sensation and we do make sure that the patient is able to urinate appropriately before we send them home. But usually for a few days or weeks afterwards; there may be a burning sensation and urgency with urination or even occasional blood with urination.

This is normal and can be usually managed with some medication. For GYN brachytherapy, there is some exposure also to the bladder and to the rectum from these brachytherapy implants and some urinary irritation and diarrhea can be associated with these treatments.

Host: I want to talk a little bit more about the newer, more innovative brachytherapy that you mentioned before. I think you called it the high dose brachytherapy that George Washington Hospital will be able to offer soon. Tell us a little bit about that and who is that for?

Dr. Rao: Yes. So, this type of brachytherapy is known as high dose rate brachytherapy. This is as opposed to the older types of brachytherapy which use lower energy and lower dose rate sources such as iodine or palladium. The high dose rate brachytherapy uses a new type of radiation source called iridium 192. The device that this source comes in is called the Flexatron and it is multi-purpose device that can be used for treating prostate cancers, GYN cancers, breast cancers and many other different kinds of malignancies.

The benefit of using this high dose rate source is that the treatment is done faster. So, as an example, in the old days when we placed prostate seeds; the prostate seeds would have a half life of 60 days so the patient would be continuously soaking up radiation over the course of months until the seed ends up decaying. With the high dose rate brachytherapy; the source is only inside the patient for several minutes. And then the source is taken out of the patient and the treatment is done.

So, the length of exposure of the patient is much lower. This allows us to give a more convenient treatment because of the shorter length of exposure and we also expect the toxicity to be less because we are giving a lower total dose of radiation. So, certainly, we believe that this will be beneficial.

Host: Yeah, I think and Dr. Rao what you said there at the end is important because I think some listeners may here high dose radiation, right and that might scare them a little bit. But because of the decrease of exposure time and overall, it’s actually a lesser amount of radiation you expect that side effects could actually be more minimized. That’s fascinating that that’s coming to George Washington University Hospital. You know just to kind of summarize Dr. Rao right now, why don’t you just tell us a little bit. What do you really want people to know about brachytherapy?

Dr. Rao: I think that brachytherapy is an excellent type of radiation treatment and that any patient who has a GYN cancer or a prostate cancer should ask their radiation oncologist if brachytherapy is an option for them. In many cases, it’s an alternative to external beam radiation treatment so that the treatment is much more convenient and there is decreased toxicity because of the volume is decreased and finally, we expect that brachytherapy should have at least as good of a cure rate as other types of radiation treatment and even surgery.

Now, one more thing is that there is emerging evidence that for prostate cancer certain types of prostate cancer, the use of brachytherapy either alone or in addition to a short course of external beam radiation may actually provide even better results compared to external radiation alone.

Now the jury is still out on this and we are still collecting more data, but it’s an exciting development.

Host: That’s wonderful. Dr. Rao, I want to thank you for the work that you’re doing and also thank you for coming on the show today. You’re listening to GW Medical Faculty Associates Podcast. For more information, go to www.gw.doc.com, that’s www.gwdocs.com. I’m Dr. Mike Smith. Thanks for listening.