Impact of prostate cancer national guidelines on brachytherapy monotherapy practice patterns.

Original Article Impact of National Guidelines on Brachytherapy Monotherapy Practice Patterns for Prostate Cancer Yolanda D. Tseng, MD 1 ; Alan T. Paciorek, BS 2 ; Neil E. Martin, MD, MPH 3 ; Anthony V. D’Amico, MD, PhD 3 ; Matthew R. Cooperberg, MD, MPH 2 ; and Paul L. Nguyen, MD 3 BACKGROUND: In 1999 and 2000, 2 national guidelines recommended brachytherapy monotherapy (BT) primarily for treatment of low-risk prostate cancer but not high-risk prostate cancer. This study examined rates of BT use before and after publication of these guidelines, as compared with 4 other treatment options. METHODS: From 1990 to 2011, 8128 men with localized prostate cancer ( T3cN0M0) were treated definitively within the Cancer of the Prostate Strategic Urologic Research Endeavor (CaPSURE) registry with 1 of 5 primary treatments: BT, external beam radiotherapy (EBRT), EBRT with androgen deprivation therapy, EBRT1BT, or radical prostatectomy. Men were categorized into low-, intermediate-, and high-risk groups based on the guidelines’ risk-group definitions. Within each risk group, logistic regression was used to estimate odds ratios (OR) comparing BT with other treatment options between the 1990-1998 and 1999-2011 periods, adjusting for age, disease characteristics, and clinic type. RESULTS: In total, 1117 men received BT alone for low- (n 5 658), intermediate- (n 5 244), or high-risk disease (n 5 215). BT comprised 6.1% of all treatments in 1990-1998 versus 16.6% in 1999-2011 (P <.01). The odds of BT use remained increased after adjusting for potential confounders (OR 5 3.06; P <.001) and was seen among low- (OR 5 4.52; P <.001), intermediate- (OR 5 2.67; P <.001), and even high-risk groups (OR 5 2.11; P <.001). CONCLUSIONS: National guidelines did not appear to influence practice patterns, as BT monotherapy use increased relative to other treatments from the 1990-1998 to 1999-2011 periods in unfavorable risk groups including men with high- C 2013 American Cancer Society. risk prostate cancer. Cancer 2014;120:824–32. V KEYWORDS: brachytherapy, prostate cancer, guidelines, public health policy, radiotherapy. INTRODUCTION Although permanent prostate brachytherapy (BT) monotherapy is an established treatment option for low-risk prostate cancer, 1-4 its appropriateness for men with intermediate- or high-risk disease is less well defined. Historically, these patients were not considered suitable candidates given that the higher predicted risk 5 of extraprostatic disease may not adequately be treated with BT alone. These concerns were in part confirmed by a large, observational cohort study published in 1998. Among the 1872 men treated with either BT monotherapy or radical prostatectomy (RP), biochemical outcomes were similar among men with low-risk disease, but inferior among men who received BT monotherapy for intermediate- or high-risk disease. 6 In 1999, the American Brachytherapy Society (ABS) published its recommendations that BT monotherapy was an appropri- ate treatment for low-risk patients, but required supplementation with external beam radiotherapy (EBRT; ie, EBRT1BT) if used as definitive treatment for high-risk disease. 7 They recommended that intermediate-risk patients be evaluated on a case-by-case basis. In the 2000 National Comprehensive Cancer Network (NCCN) practice guidelines, BT monotherapy was recommended only for low-risk disease. 8 Several retrospective studies have since suggested that biochemical and even prostate-specific survival outcomes are not significantly different among men who received BT monotherapy for intermediate-risk disease, as compared with RP 9 or EBRT. 10,11 Given conflicting retrospective studies 12 and lack of prospective, randomized data to guide physicians on the relative benefit of BT monotherapy, we evaluated within a large US-based registry the impact of the 1999 7 and 2000 8 national guidelines on BT monotherapy utilization for definitive treatment of localized prostate cancer. Corresponding author: Yolanda D. Tseng, MD, Harvard Radiation Oncology Program, 75 Francis Street, ASB L2, Boston, MA 02115; Fax: (617) 632-4247; ydtseng@partners.org Harvard Radiation Oncology Program, Boston, Massachusetts; 2 Department of Urology, University of California, San Francisco, California; 3 Department of Radia- tion Oncology, Brigham and Women’s Hospital and Dana-Farber Cancer Institute, Boston, Massachusetts DOI: 10.1002/cncr.28492, Received: September 10, 2013; Revised: October 22, 2013; Accepted: October 24, 2013, Published online December 2, 2013 in Wiley Online Library (wileyonlinelibrary.com) Cancer March 15, 2014