Radiation Therapy for Prostate Cancer
UT Southwestern has one of the most advanced programs for the radiotherapy treatment of prostate cancer in the country. With a program that has emphasized a newer technique called stereotactic radiation body radiation therapy (SBRT), our physicians pioneered the five-treatment stereotactic regimen for early- and intermediate-risk prostate cancer that is now being adopted at many progressive centers worldwide.
Stereotactic body radiation therapy (SBRT)
UT Southwestern has been leading efforts to explore the safety and efficacy of SBRT for over a decade. Most recently, a study published by our researchers shows that SBRT offers a higher cure rate for cancer than more traditional approaches. That study – the first trial to publish five-year results from SBRT treatment for prostate cancer – found a 98.6 percent cure rate with SBRT among 91 patients.
SBRT uses advanced imaged guidance to very precisely deliver radiation from many different angles. While each beam is relatively weak on entry, the dose at the convergence point is enough to kill a tumor in just five treatments versus 45 or more treatments with standard therapy. To make the SBRT treatments safer, current clinical trials at UTSW are using a biodegradable rectal spacer gel to protect the rectum. UTSW is currently the only accredited site in Texas at which this spacer gel can be used.
Currently SBRT is being evaluated here for the treatment of high-risk prostate cancer patients as well.
Intensity modulated radiation therapy (IMRT)
For patients who are not candidates for stereotactic therapy, intensity modulated radiation therapy (IMRT) is a state-of-the-art technology that is used to treat difficult-to-reach tumors such as prostate cancer. IMRT is delivered using multiple beams of radiation that conform the dose in three dimensions to match the exact shape of the target. IMRT can also modulate the intensity of the dose, meaning that a higher dose can be given to the tumor target while lower doses can be used to spare normal tissue or sensitive structures.
Brachytherapy (Seed Implants)
Another available option is brachytherapy, in which radioactive seeds are implanted in the prostate to deliver radiation and treat cancer from within. The permanent seeds, which lose their radioactivity at a predetermined rate after several weeks, are implanted by needle under anesthesia in an outpatient procedure room. A dedicated brachytherapy specialist with advanced training in placing these implants performs these procedures. Brachytherapy is able to achieve a very conformal dose in most instances, meaning the radiation stays within the defined target with no entry radiation and very little spillover into surrounding normal tissue.
Finally, researchers here are actively exploring ways to improve the safety and reduce the side effects of prostate cancer treatment. Quality of life and the ability to maintain urinary and sexual function after treatment are of prime consideration when choosing a treatment in consultation with your physician. Our radiation oncologists work closely with the urologists, medical oncologists, and other cancer specialists at UT Southwestern to bring about the best possible outcome.