Skip to Content

Published on May 09, 2017

SBRT: A Powerful Prostate Cancer Treatment Option

Kenon Qamar, MD

Kenon Qamar, MD

Dr. Qamar earned his medical degree from the University of Kansas School of Medicine in Kansas City. He completed his residencies in radiation oncology at the University of Kansas School of Medicine and the University of Louisville (KY) Hospital-James Graham Brown Cancer Center.

Patients with low-, intermediate- and select high-risk prostate cancer have a better option for radiation treatment in the Northland. The advanced technology of the Trilogy® linear accelerator at North Kansas City Hospital uses stereotactic body radiation therapy to pinpoint prostate cancer in a way that is safer, faster and more cost-effective than traditional radiation therapy.

Pinpoint Accuracy

Similar to stereotactic radiosurgery used to treat brain tumors, SBRT has been used for pancreatic, lung and other forms of cancer. “As the name implies, the treatment is targeted and precise,” said Kenon Qamar, MD, a radiation oncologist with The University of Kansas Cancer Center on the North Kansas City Hospital campus. “Stereotactic means there is a well-defined 3-D coordinate system that localizes the prostate, so the linear accelerator can deliver the radiation with pinpoint accuracy.”

Dr. Qamar and Mark A. Thompson, MD, a radiation oncologist with KUCC, offer advanced prostate cancer treatment options through NKCH’s partnership with KUCC.

Because the prostate naturally shifts within the body, it can be a challenge to precisely target with radiation. Now, Calypso® beacons implanted directly into the prostate communicate with the linear accelerator to show the position of a patient’s tumor 25 times per second. Radiation is delivered only when the prostate is in the pre-determined field. Any movement that changes the tumor position away from the beam causes the beam to shut off automatically, sparing exposure to critical structures, such as the bowel, bladder and femoral heads.

Broadly accepted for low- and intermediate risk patients, high-risk patients are also potential candidates for SBRT. “It can be used for these cancers as long as the cancer is localized, but it’s not intended for people who have metastatic disease,” said Dr. Qamar, who added that the SBRT’s ability to control cancer is at least equal to external beam radiation, brachytherapy and surgery.

A Calypso beacon is about the
size of an uncooked grain of rice.

A multi-institutional five-year study of low- and select intermediate-risk prostate cancer patients released in 2016, found a 98.6% cure rate with SBRT. The lead author on this study noted that the five-year cure rates from surgery or conventional radiation range between 80%-90%.

Less Treatment Time

Individuals who undergo SBRT typically experience a dramatically shorter course of care when compared with conventional external beam treatment. Instead of two months of five treatments per week, patients undergoing SBRT typically have five or fewer total treatments.

“Going through 45 treatments takes a toll on patients,” Dr. Qamar said. “They end up traveling extended distances and using all kinds of personal, financial and family resources. If the patient lives an extended distance from a facility, the patient may have to stay with a loved one and go on short-term disability.”

Quality of Life

The Trilogy linear accelerator delivers ultra-precise
radiation that targets the exact site of a tumor, even
if it moves when a patient breathes, minimizing
exposure to surrounding healthy tissue.

SBRT treatments are no longer in duration than those given with external beam radiation. “Most patients have minimal side effects, and less than 5% of patients have mild to moderate long-term side effects, which generally are related to bowel and bladder function,” Dr. Qamar said.

Compared to brachytherapy, which delivers high doses of radiation to tumors via radioactive seed implants, there is no anesthesia, operating room time, bleeding risk or urinary catheter. “It’s a simple outpatient procedure,” said Dr. Qamar, adding that the burden of the patient’s copayments and net cost of care is about one-third of that with external beam radiation.

Although SBRT doses are biologically more potent, they are fewer in number, minimizing the need for some patients with intermediate- and high-risk prostate cancer to take hormone-suppressing medications. “These medications have tremendous side effects,” Dr. Qamar said. “Men lose their libido and bone density, become anemic and fatigued, and are more susceptible to getting diabetes and having cardiac events. They may be able to avoid that with SBRT.”