We used the Surveillance Epidemiology and End Results Medica
We used the Surveillance, Epidemiology, and End Results-Medicare database to identify men
diagnosed with low-risk PCa during 2010-2013. We assessed the use of prostate MRI and manage-
ment using claims in 118-92-3 surrounding PCa diagnosis. The relation of clinical and demographic
factors to receipt of MRI was evaluated with multivariable logistic regression analysis. Following
propensity score matching, we fit conditional logistic regression models to examine the association
between prostate MRI and initial management, ie, observation or definitive treatment. RESULTS Of 8144 patients with low-risk PCa, 495 (6.1%) received MRI. Use of MRI increased from 3.4% in
multivariable analysis, measures of socioeconomic status were significantly associated with the use of
prostate MRI. Following propensity score matching, receipt of prostate MRI surrounding the diagno-
sis of PCa was associated with a significantly higher likelihood of observation (odds ratio = 1.90,
95% confidence interval: 1.56-2.32). This effect persisted in sensitivity analyses attempting to
exclude treatment-planning MRIs. CONCLUSION Receipt of prostate MRI surrounding PCa diagnosis was associated with a nearly 2-fold greater
Despite national declines in screening, prostate cancer (PCa) remains the most commonly diag-nosed noncutaneous cancer among men in the
United States.1 For those with low-risk features, immedi-ate treatment has not been shown to improve cancer-spe-cific survival, and frequently impacts health-related quality of life including urinary, bowel, and sexual func-tion.2-5 Active surveillance (AS), a period of close disease observation, has emerged as a strategy to defer or avoid definitive treatment for low-risk patients, and is now
Financial Disclosure: The authors declare that they have no relevant financial interests. From the Department of Urology, Yale School of Medicine, New Haven, CT; the Yale Cancer Outcomes, Public Policy, and Effectiveness Research Center, New Haven, CT; the Department of Chronic Disease Epidemiology, Yale School of Public Health, New Haven, CT; the Department of Therapeutic Radiology, Yale School of Medicine, New Haven, CT; the Department of Radiology and Biomedical Imaging, Yale School of Medi-cine, New Haven, CT; and the Department of Internal Medicine, Yale School of Medi-
cine, New Haven, CT
regarded as the standard of care by major cancer guide-line-issuing bodies.6 Despite increases in the utilization of AS, recent estimates available through 2013 indicate that the majority of patients with low-risk PCa continue to receive definitive treatment.7,8 Although longitudinal studies support the safety of AS, uncertainty about the possibility of underestimating an indvidual’s risk of har-boring aggressive disease remains a strong motivator to treat. As a result, efforts to improve the initial characteri-zation of the disease have been advocated as a means to enhance confidence with observational management.9
In the past few years there has been a dramatic expan-sion in the support for MRI in the evaluation of men with known or suspected PCa.10 Recent studies have under-scored the ability of contemporary prostate MRI to offer high resolution anatomical assessment of the prostate including improved prediction of high-grade or high-stage disease.11 Moreover, MRI facilitates the performance of targeted MRI-guided in-bore, cognitive, or MR-ultra-sound fusion biopsies, which improve detection yields for occult higher-grade cancer that would be missed on
Published by Elsevier Inc.
systematic transrectal ultrasound guided biopsy alone. On the basis of encouraging single and multi-institutional controlled studies, prostate MRI is increasingly recom-mended as an important staging tool that can identify
occult aggressive disease and facilitate enrollment in AS.12
Despite growing enthusiasm, there is a lack of popula-tion-level evidence that addresses national utilization trends, or practical impact of prostate MRI on disease management. Therefore, we assessed the use of prostate MRI in a population-based, nationally representative cohort of Medicare beneficiaires with low-risk PCa, evalu-ated patient and healthcare level factors predictive of MRI use, and examined the association between prostate MRI and initial management with observation or defini-tive therapy. We tested the hypotheses that early MRI use was variable across socio-demographic and provider-level factors, and that use of MRI was associated with greater likelihood of observation as initial management.
MATERIALS AND METHODS
We used Surveillance, Epidemiology, and End-Results (SEER) records linked with individual level Medicare claims to identify men with PCa. The SEER-Medicare linkage provides a high level of detail regarding healthcare delivery among older Ameri-cans including clinical and demographic characteristics, treat-ments received, and subsequent outcome.13 The most recent linkage released in April 2017 includes patients diagnosed through 2013. Patients included in this study were diagnosed with nonmetastatic, lymphnode negative, first primary, low-risk PCa at the age of ≥ 66 years in 2010-2013 according to the D’Amico classification: PSA<10 ng/mL, Gleason score ≤ 3 + 3, and clinical stage ≤ T2a.14 Patients were excluded on the basis of absence of Medicare Parts A and/or B, health maintenance organization membership in the 12 month period preceding diagnosis until December 31, 2014, or death, unknown date of diagnosis, incidental detection of PCa on death certificate or at autopsy, missing tumor grade, stage or PSA level. To assure patients received MRI or treatment, we further excluded patients who died within 1 year after diagnosis.