AUA 2018: Disparities in the Diagnosis and Management of Metastatic Prostate Cancer in Young Men 

San Francisco, CA (UroToday.com) Decreased screening for prostate cancer may lead to delayed presentation [1], resulting in more men presenting with metastatic prostate cancer. There has been remarkable improvement in treatment in the metastatic hormone naïve setting. This is particularly true with regards to the recent STAMPEDE and LATITUDE trial demonstrating remarkable outcomes for patients treated with abiraterone and prednisone compared to placebo [2-3], and studies demonstrating improved survival among those treated with docetaxel for high-volume disease [4-6]. 



While the usual male with metastatic prostate cancer is likely an elderly gentleman of Caucasian race, little is known regarding younger men who are diagnosed with metastatic prostate cancer, in whom disease trajectory and outcome may be distinct from older men. As such,  at the AUA 2018 prostate cancer epidemiology session, Dr. Lu and colleagues aimed to identify sociodemographic factors associated with the diagnosis of metastatic prostate cancer in young men using a population-level analysis.  

For this study, the authors used the National Cancer Database to identify 186,578 men with prostate cancer diagnosed between 2004 and 2014. Patients were stratified by age ≤ 55 and clinicodemographic factors were examined to determine associations with the diagnosis of metastatic (M1 or N1) prostate cancer. Descriptive statistics were used to compare characteristics across age strata, including the primary outcomes of initial treatment and utilization of palliative care services. Multivariable logistic regression models were constructed to assess factors associated with metastatic vs. localized disease at presentation and treatment received.  
Among the 186,578 men <55 years of age diagnosed with prostate cancer, 9,888 had metastatic disease at presentation. Metastatic versus localized disease at diagnosis was associated with lack of insurance (OR 4.58, 95%CI 4.23-4.96), greater distance from facility (OR 2.04, 95%CI 1.18-3.51), higher degree of comorbidity (OR 1.66, 95%CI 1.44-1.91), treatment in an academic setting (OR 1.20, 95%CI 1.15-1.26), lower local education level (OR 1.20, 95%CI 1.09-1.31), and lower income (OR 1.15 95%CI 1.05-1.26). African-American race was associated with metastatic disease in men >55 years, but not those younger than 55. Receipt of referral to palliative care in young men was associated with lack of insurance (OR 2.21, 95%CI 1.79-2.74]) or government insurance (Medicare or Medicaid; OR 1.84, 95%CI 1.55-2.20) compared to privately insured patients, and treatment in community setting (OR 1.34, 95%CI 1.16-1.55). Receipt of palliative care in older men had similar characteristics, but with additional factors of higher comorbidity index (OR 1.43, 95%CI 1.31-1.56), lower income (OR 1.37, 95%CI 1.23-1.51), and lower education level (OR 1.27, 95%CI 1.15-1.42). Caucasian race (OR 1.49, 95%CI 1.23-1.81) and shorter distance to facility (OR 0.04, 95%CI 0.002-0.74) were significantly associated with receipt of multi-agent chemotherapy for young men.  

 The strength of the current study is the population-level approach, allowing a sufficient sample size and event rate to assess predictors of metastatic disease and those receiving palliative care consultations. A limitation of the study is that the National Cancer Database does not have disease specific survival outcomes precluding survival analyses for this cohort. The authors concluded that among younger men with prostate cancer, sociodemographic factors (including African American race) were significantly associated with the diagnosis of metastatic prostate cancer, as well as initial treatment or receipt of palliative care.  

Presented By: Amanda Lu, Yale School of Medicine, New Haven, CT 
Co-Authors: Kamyar Ghabili Amirkhiz, Kevin Nguyen, Walter Hsiang, Michael Leapman, New Haven, CT 

References: 
1. Jemal A, Fedewa SA, Ma J, et al. Prostate cancer incidence and PSA testing patterns in relation to USPSTF screening recommendations. JAMA 2015;315(19):2054-2061. 
2. James ND, de Bono JS, Spears MR, et al. Abiraterone for Prostate Cancer Not Previously Treated with Hormone Therapy. N Engl J Med. 2017;377(4):338-351. 
3. Fizazi K, Tran N, Fein L, et al. Abiraterone plus Prednisone in Metastatic, Castration-Sensitive Prostate Cancer. N Engl J Med. 2017;377(4):352-360. 
4. James ND, Sydes MR, Clarke NW, et al. Addition of docetaxel, zoledronic acid, or both to first-line long-term hormone therapy in prostate cancer (STAMPEDE): survival results from an adaptive, multiarm, multistage, platform randomised controlled trial. Lancet. 2016;387(10024):1163-1177. 
5. Sweeney CJ, Chen YH, Carducci M, et al. Chemohormonal Therapy in Metastatic Hormone-Sensitive Prostate Cancer. N Engl J Med. 2015;373(8):737-746. 
6. Gravis G, Boher JM, Joly F, et al. Androgen Deprivation Therapy (ADT) Plus Docetaxel Versus ADT Alone in Metastatic Non castrate Prostate Cancer: Impact of Metastatic Burden and Long-term Survival Analysis of the Randomized Phase 3 GETUG-AFU15 Trial. Eur Urol. 2016;70(2):256-262. 

Written by: Zachary Klaassen, MD, Urologic Oncology Fellow, University of Toronto, Princess Margaret Cancer Centre Twitter: @zklaassen_md at the 2018 AUA Annual Meeting - May 18 - 21, 2018 – San Francisco, CA USA