New Treatments for Prostate Cancer
There have been many advancements in radiation treatment over the years. External beam radiotherapy, intensity modulated radiotherapy (IMRT) and 3D-conformal radiation therapy all accelerate subatomic particles called electrons to generate waves of high-energy photon radiation. Proton beam therapy uses subatomic particles called protons. Neutron beam therapy uses subatomic particles called neutrons.
Proton Beam Therapy
In March 2013, SCCA Proton Therapy, A ProCure Center opened at Northwest Hospital, making proton therapy available to cancer patients in the Pacific Northwest for the first time. SCCA medical oncologists and radiation oncologists are excited to have the opportunity to utilize proton therapy in treating prostate cancer. Research studies have demonstrated the efficacy of proton therapy, its relative safety even when higher doses are utilized—along with a low incidence of incontinence and bowel dysfunction for men undergoing this treatment. The results of studies done thus far suggest excellent outcomes in patients treated with proton beam therapy. The results are approximately like those seen in patients treated with high doses of IMRT. The potential improvements in side effects remain a topic of some debate, as some studies suggest a higher rate of rectal toxicity than with IMRT. Learn more about proton therapy for prostate cancer.
GPS for the Body
In 2008, SCCA brought in new technology that improves external beam radiation treatment. This is the Calypso System, now referred to as GPS for the Body, manufactured by Calypso Medical. SCCA radiation oncologists were critical in developing this system. It provides clinicians with an innovative solution for target localization and continuous monitoring of the prostate in real time during delivery of radiation therapy to make sure that radiation therapy treats just your cancer and not your surrounding organs.
The U.S. Food and Drug Administration recently approved use of the prostate cancer treatment Provenge, made by Dendreon Corporation of Seattle. The company said the treatment will be available at 50 clinical sites around the country, including Seattle Cancer Care Alliance. SCCA was the location for several of the clinical studies to test Provenge prior to regulatory approval. These were led by Dr. Celestia S. Higano, MD, a medical oncologist who specializes in prostate cancer and a professor of medical oncology at the University of Washington. Read more about Provenge and its availability at SCCA.
Therapy for High-Risk Cancer
One in five men are diagnosed with “high- risk” localized prostate cancer. In this group, which accounts for the majority of the 27,000 prostate cancer deaths seen in the United States each year, cure is achieved less than 50 percent of the time. These cancers have a propensity to spread even when, by all clinical appearances, the disease is localized. SCCA is at the forefront of developing new treatment strategies focused on this subset of men with high-risk prostate cancer. According to Bruce Montgomery, MD, a new generation of systemic therapies is showing clinical promise when combined with surgery or radiation for high-risk tumors. These approaches involve treating both the cancer in the prostate and any cancer that might have spread early in the development of the disease. See Treating High-Risk Prostate Cancer for more information.
Approximately half of men diagnosed with prostate cancer and treated with surgery or radiation have cancer that is at very low risk for causing serious problems for them in the future. Although it seems counterintuitive that men who have cancer may not need therapy, it is clear that most men with low-grade cancer, particularly those men over age 70, will have evidence of prostate cancer that never causes problems over their lifetime. This suggests that many prostate tumors grow very slowly and never progress to clinical cancer, even over decades. The extensive use of prostate-specific antigen (PSA) screening over the past 20 years has also increased the number of men diagnosed with cancer, even though many would never have needed treatment.
The open issue of how to best measure PSA or other markers to diagnose cancer is a different question from who needs treatment after a diagnosis of prostate cancer. For a large number of men therapy can be safely delayed, perhaps indefinitely. This approach is termed “active surveillance,” which is different from the old concept of “watchful waiting,” which may have involved too much waiting and not enough treatment when it was needed.
In active surveillance, men are monitored with serial PSA measurements and repeated prostate biopsies to carefully check for any changes that may suggest the need for treatment.
SCCA is leading a multi-institutional study of how best to determine who needs therapy and how to detect clinically significant and insignificant cancer. This study is sponsored by the Canary Foundation.
Some promising new treatments are only available in clinical trials. Ask your doctor if there is a clinical study that might be right for you.