The proportion of men with high-risk localized prostate cancer undergoing radical prostatectomy (RP) increased dramatically from 2004 to 2013 such that by the end of the study period, RP and external beam radiation therapy (EBRT) were used with similar frequency in this patient population, new findings suggest.
In an analysis of data from 127,391 patients with high-risk localized prostate cancer (PCa) in the National Cancer Data Base (NCDB), a team led by Scott E. Eggener, MD, of the University of Chicago, found initial use of RP increased from 26% to 42%, whereas the initial use of EBRT decreased from 49% to 42%, according to a report published in Prostate Cancer and Prostatic Diseases (2017; published online ahead of print). Compared with men treated in 2004, those treated in 2013 were 51% more likely to undergo RP.
Of a total of 127,391 men in the study, 45,978 (36%) received RP. Increasing PSA at diagnosis was associated with decreasing use of RP. For example, 41% of men with a PSA level of 4.1 to 10 ng/mL underwent RP compared with 29% of men who had a PSA level of 20 ng/mL or higher. Patients with a biopsy Gleason score of 8–9, with or without any primary Gleason 5 patterns, had a significant 19% decreased likelihood of RP use compared with patients who had a Gleason score of 6 or less.
The patient population had a median follow-up of 4.4 years. The median overall survival for men was 8.3 years for men who received no treatment, 9.9 years for those treated with EBRT plus androgen deprivation therapy (ADT), and 5.7 years for those who received ADT alone. Median survival was not reached for men treated with RP. The 10-year overall survival was 41% for no treatment, 77% for RP, 49% for EBRT plus ADT, and 24% for ADT alone. Compared with RP, no treatment was associated with a 3-fold higher risk of death. EBRT with ADT and ADT alone were associated with a 1.6- and 3.4-fold increased risk of death, respectively.
A number of possible reasons could explain an increase in the use of RP for high-risk localized PCa, the authors noted. Findings from population-based studies have suggested an improved cancer-specific survival benefit with RP compared with radiation. “Although these studies were limited by their retrospective design and unmeasured confounding variables, they were likely influential on patients and physicians,” said Adam Weiner, MD, of Northwestern University in Chicago, the study’s primary author.
Among the studies suggesting better cancer-specific survival with RP compared with radiotherapy is a systematic review and meta-analysis of 19 studies by Christopher J.D. Wallis, MD, published in European Urology (2016;70:21-30). The researchers concluded that radiotherapy was associated with a 2-fold increased risk of death compared with RP in adjusted analyses.
Strengths of the study by Dr. Eggener’s team include the large and diverse patient population captured in the NCDB, which, unlike other datasets, such as the Surveillance, Epidemiology and End Results (SEER) database, provides valuable information on ADT use and the order in which treatments were received to accurately discern initial treatments. The NCDB, however, is a hospital-based cancer registry, not population-based. “The data from the NCDB should be interpreted as generalizable to hospitals similar to those included in its registry,” the authors noted.
Source: Weiner AB, Matulewicz RS, Schaeffer EM, et al. Contemporary management of men with high-risk localized prostate cancer in the United States. Prostate Cancer Prostatic Dis 2017; published online ahead of print.