Methods | The study was approved by the VA New York Harbor institutional review board with a waiver of informed consent. Using VA’s Central Data Warehouse, we examined treatment patterns for veterans diagnosed with low-risk prostate cancer (prostate-specific antigen [PSA] <10 ng/mL, Gleason ≤6, and stage cT1/T2a) from January 2005 through November 2015. Our dependent variable was receipt of curative therapy within 1 year of diagnosis (including androgen deprivation monotherapy), determined by administrative codes. Linkage to Medicare was performed to identify tests or treatment performed outside the VA for men 65 years or older. Men with PSA less than 1 ng/mL during follow-up were also classified as likely having received curative treatment outside the VA. Untreated veterans were classified as receiving conservative management, subdivided into active surveillance (≥2 PSAs and 1 biopsy within 2 years after diagnosis) or watchful waiting. The final date of follow-up was November 16, 2017.
We explored the use of conservative management over time, stratified by age. The Cochran-Armitage test was used to examine trends over time, and logistic regression was used to identify the association between year of diagnosis and conservative management, adjusting for age, race, marital status, PSA, comorbidity, and region. Men without a PSA, biopsy, or treatment recorded within 2 years were excluded. An analysis was performed using SAS Enterprise Guide (SAS Institute), version 7.1, and tests were 2-sided at an α of .05.
Results | Among 125 083 veterans with low-risk prostate cancer, mean age was 64 years (SD, 7) and mean PSA was 5.4 ng/mL (SD, 2.1). Of the 65 142 (52%) who were treated, 65% were identified through VA claims, 25% by PSA less than 1 ng/mL, and 10% through Medicare claims. Of 59 941 veterans (48%) who received conservative management, 37 717 (30%) received watchful waiting and 22 224 (18%) received active surveillance. Utilization of conservative management increased among men younger than 65 years (27% in 2005 to 72% in 2015) and 65 years or older (35% in 2005 to 79% in 2015); both P for trend <.001 (Figure). The increase was primarily due to greater use of active surveillance (4% in 2005 to 39% in 2015 in men <65 y; 3% in 2005 to 41% in 2015 in men ≥65 y).
Figure. The proportion of US Veterans with Low-Risk Prostate Cancer Receiving Conservative Management (Active Surveillance or Watchful Waiting) from 2005-2015 (N = 125 083), by Agea
On multivariable analysis, more recent years were associated with greater odds of conservative management, as were increasing age, black race, unmarried status, higher PSA, increasing comorbidity, and geographic region (Table). Men older than 75 years, higher PSA, and greater comorbidity were more likely to receive watchful waiting than active surveillance.
Table. Multivariable Analysis of Factors Associated With Conservative Management (Active Surveillance or Watchful Waiting) vs Active Treatment and Active Surveillance vs Watchful Waiting Among Veterans With Low-Risk Prostate Cancera
Discussion | Utilization of conservative management has increased significantly among US veterans with low-risk prostate cancer, suggesting a substantial reduction in overtreatment during the past decade. These rates are higher than prior US studies in different healthcare settings. In the Surveillance, Epidemiology, and End Results (SEER)–Medicare–linked database from 2010-2011, only 32% of suitable patients received conservative management.3 In another registry of 45 US community-based urology practices, 40% of low-risk patients received conservative management from 2010-2013.2 Within a Michigan quality improvement collaborative (2012-2016), the proportion of low-risk patients managed by active surveillance varied significantly across practices (range, 30.2%-72.6%).6 By contrast, international rates of conservative management are considerably higher. For example, in Sweden, 74% of low-risk patients underwent active surveillance in 2014.4
Limitations of this study include possible nondetection and misclassification of treatment outside the VA that was not captured, difficulty distinguishing active surveillance vs watchful waiting using administrative codes, and inability to determine participation in shared decision making. Strengths include a large, racially diverse population of US veterans, providing comprehensive nationwide data on treatment trends.
Despite some regional variation suggesting additional room for improvement in the VA, these data suggest that an integrated health care system with equitable access for patients and without volume-based incentives for physicians may overcome many barriers to guideline-recommended conservative management.
Authors: Stacy Loeb, MD, MSc1; Nataliya Byrne, BA2; Danil V. Makarov, MD, MHS1; et al
1. Manhattan Veterans Affairs Medical Center, New York, New York
2. Department of Urology, New York University, New York
3. Department of Population Health, New York University, New York
Author Contributions: Ms. Walter had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.
JAMA. Published online May 15, 2018. doi:10.1001/jama.2018.5616
Concept and design: Loeb, Makarov, Lepor, Walter.
Acquisition, analysis, or interpretation of data: Loeb, Byrne, Makarov, Walter.
Drafting of the manuscript: Loeb.
Critical revision of the manuscript for important intellectual content: All authors.
Statistical analysis: Walter.
Obtained funding: Loeb, Makarov.
Administrative, technical, or material support: Byrne, Lepor.
Supervision: Loeb, Lepor.
References
1. Chen RC, Rumble RB, Loblaw DA, et al. Active surveillance for the management of localized prostate cancer (Cancer Care Ontario Guideline). J Clin Oncol. 2016;34(18):2182-2190.
2. Cooperberg MR, Carroll PR. Trends in management for patients with localized prostate cancer, 1990-2013. JAMA. 2015;314(1):80-82.
3. Moschini M, Fossati N, Sood A, et al. Contemporary management of prostate cancer patients suitable for active surveillance. Eur Urol Focus. 2016. doi:10.1016/j.euf.2016.06.001
4. Loeb S, Folkvaljon Y, Curnyn C, Robinson D, Bratt O, Stattin P. Uptake of active surveillance for very-low-risk prostate cancer in Sweden. JAMA Oncol. 2017;3(10):1393-1398.
5. Loeb S, Curnyn C, Fagerlin A, et al. Qualitative study on decision-making by prostate cancer physicians during active surveillance. BJU Int. 2017;120(1):32-39.
6. Auffenberg GB, Lane BR, Linsell S, Cher ML, Miller DC. Practice- vs physician-level variation in use of active surveillance for men with low-risk prostate cancer. JAMA Surg. 2017;152(10):978-980.
Conflict of Interest Disclosures: All authors have completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Dr. Loeb reported consulting for Lilly, MDx Health, GenomeDx, and General Electric and receiving personal fees from Astellas, Sanofi, Minomic, and Boehringer Ingelheim. Dr. Makarov reported consulting for the US Food and Drug Administration. Dr. Lepor reported previously holding shares in SonaCare Medical and receiving research support from and serving on the advisory board for Genomic Health. No other disclosures were reported.
Funding/Support: This study was supported by the Edward Blank and Sharon Cosloy Blank Family Foundation, the Gertrude, and Louis Feil Family; and by grants DOH01-C30697GG-3450000 from the New York State Department of Health, P30CA016087 from the Laura and Isaac Perlmutter Cancer Center at New York University Langone Medical Center, the Prostate Cancer Foundation, K07CA178258 from the National Institutes of Health (NIH) (Dr Loeb), and CDA11-257 and CDP 11-254 from the US Department of Veterans Affairs (Dr Makarov).
Role of the Funder/Sponsor: The funders had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.
Disclaimer: The content is solely the responsibility of the authors and does not represent the official views of the NIH.