A new study suggests active surveillance may be an initial approach for men with favorable intermediate-risk prostate cancer but further research results are needed, according to a study published online by JAMA Oncology (2015; doi:10.1001/jamaoncol.2014.284).
According to the National Comprehensive Cancer Network (NCCN) guidelines, active surveillance is considered for patients with low-risk prostate cancer and a life expectancy of at least 10 years. Active surveillance means monitoring the course of prostate cancer with the expectation to start treatment if the cancer progresses.
No direct comparison has been made between favorable intermediate-risk and low-risk prostate cancer with regard to prostate cancer-specific mortality or all-cause mortality following high-dose radiotherapy such as brachytherapy. The authors noted such comparisons are clinically relevant because of the active surveillance guidelines for men with low-risk prostate cancer, according to the study background.
Ann C. Raldow, MD, of Brigham and Women’s Hospital in Boston, Massachusetts, and coauthors studied 5,580 men (midpoint age, 68 years) with localized prostate cancer treated between 1997 and 2013. They estimated and compared the risk of prostate cancer-specific mortality and all-cause mortality following brachytherapy among men with low and favorable intermediate-risk prostate cancer.
After a median of nearly 8 years of follow-up, 605 men died (10.84% of the total group) and, among those, 34 men died of prostate cancer (5.62% of total deaths). The authors found that men with favorable intermediate-risk prostate cancer did not have a significantly increased risk of prostate cancer-specific mortality and all-cause mortality compared with men with low-risk prostate cancer.
Eight-year estimates for prostate cancer-specific mortality were low at 0.48% for men with favorable intermediate-risk prostate cancer and 0.33% for men with low-risk prostate cancer. The estimates for all-cause mortality were 10.45% for men with favorable intermediate-risk prostate cancer and 8.68% for men with low-risk prostate cancer, according to the results.
“Despite potential study limitations, we found that men with low-risk prostate cancer and favorable intermediate-risk prostate cancer have similar and very low estimates of prostate cancer-specific mortality and all-cause mortality during the first decade following brachytherapy. While awaiting the results of ProtecT, the randomized trial of active surveillance vs. treatment, our results provide evidence to support active surveillance as an initial approach for men with favorable intermediate-risk prostate cancer,” the study concluded.
An accompanying editorial (doi:10.1001/jamaoncol.2014.103) by Fred Saad, MD, of the University of Montreal, Canada, stated, “One of the most important findings is that favorable intermediate-risk cancers can be very well controlled with brachytherapy. This is very worthwhile information.”
“Although I am a urologist who has been practicing active surveillance for most of my low-risk patients for many years, I suggest that we continue to be very cautious, and extremely selective, in offering active surveillance to patients with any features of intermediate-risk prostate cancer,” Saad concluded.