Radiation is one of the therapies used to kill cancer cells by precisely targeting them with high energy X-rays. Radiation therapy for prostate cancer can mean several weeks of treatment for some patients. NHRMC offers Stereotactic Body Radiation Therapy (SBRT), which involves a much shorter course of treatment, as a treatment option for some prostate cancer patients, particularly those who are considered in the low or favorable intermediate risk groups for prostate cancer.
SBRT is a type of external beam radiation therapy, which delivers radiation from outside of the body. SBRT delivers a targeted very high dose of radiation to the tumor with high precision using a single or a small number of fractions or doses while minimizing damage to the surrounding healthy tissue.
1. SBRT treatment can be completed in five days
Technological advances and imaging guidance help the radiation oncologist safely deliver high doses of radiation to small, well defined targets in the body. This shortens the length of time needed for treatment, offering an advantage for patients with busy schedules or who may have to travel a lengthy distance for treatment. "Often what we used to do for prostate cancer was give really low doses of radiation every day, Monday through Friday for 9 weeks; so, it was a long, drawn out process," said Michael A. Papagikos, MD, a radiation oncologist with NHRMC Radiation Oncology. "We did that because we didn't want to give too much radiation to the bladder or the rectum. By giving the radiation really slowly you can make it really safe, but it didn't make it convenient. Now we can take that same goal that used to take nine weeks, and we can get it done over five days."
2. Some patients are better candidates for SBRT than others
“SBRT is an acceptable standard of care option for men with very low, low, or favorable intermediate risk prostate cancer," Dr. Papagikos said, adding that use of SBRT for more aggressive forms of prostate cancer is still being investigating.
"For most of the patients that I see with low or very low risk, we spend a lot of time talking about active surveillance," Dr. Papagikos said. Active surveillance for prostate cancer refers to not providing any treatment but monitoring the cancer closely. It's used for patients diagnosed with prostate cancer who may not ever need to be treated or who may need treatment later.
"We’ll consider using SBRT mostly on those with favorable intermediate risk prostate cancer who need treatment but who may not need a lot of treatment,” Papagikos said.
3. What are the side effects of SBRT?
"SBRT is generally tolerated really well,” Dr. Papagikos said. "Most people drive themselves back and forth from appointments and continue with regular activities and routines."
Some short-term side effects include fatigue and urinary frequency. "Most folks don't have any side effects after the first couple of treatments, and then towards the latter half of it—if they are going to develop some side effects—that’s when they'll start to notice it,” Dr. Papagikos said. "Side effects will probably persist for about a week or 10 days after the last treatment."
4. Knowing your options for treatment is important
Dr. Papagikos said patients should be given the opportunity to discuss with providers both surgery and radiation therapy as treatment options for prostate cancer. “They've done randomized controlled trials where they've compared surgery with nonsurgical management, and usually the most common nonsurgical management would be radiation therapy," he said. "We know that there's no difference in survival rates; so, there's no difference in terms of outcomes."
"Most of the guidelines, even the guidelines of the American Urological Association, suggest that if you're diagnosed with prostate cancer you should consult with a urologist who does prostatectomies and you should also meet with a radiation oncologist to see what the radiation therapy options are," said Dr. Papagikos. "There are some subtle differences, that may nudge a particular person into being a better surgical candidate or a better radiation candidate, but I would say most men are candidates for both and should be given the opportunity to discuss both."
5. Why qualifying prostate cancer patients may consider SBRT
• Shortened length of time needed for treatment
• Cancer control rates of SBRT are equivalent to those of brachytherapy, conventional external beam radiotherapy, or surgery for men with low-risk prostate cancer. It's being investigated for men with high-risk prostate cancer.
• Though SBRT delivers radiation over a much shorter time period than conventional external beam radiation therapy, the acute short-term side effects appear to be the same.
• SBRT can be delivered safely and effectively for patients who are not ideal brachytherapy candidates or who do not want to deal with the special precautions required for patients who undergo brachytherapy for prostate cancer, a radiation therapy procedure in which radiation seeds are implanted into the prostate.
• SBRT is a good option for men who have an elevated risk of anesthesia.
Learn more about SBRT by visiting the External Beam Radiation Therapy website.