Presentation Authors: Allison May*, Joshua Trierweiler, Anirudh Guduru, Johar Syed, Facundo Davaro, Sameer Siddiqui, Zachary Hamilton, Saint Louis, MO
Introduction: Standard of care treatment based on national guidelines for men with clinically localized high risk prostate cancer includes radical prostatectomy (RP) or external beam radiation therapy (EBRT) with androgen deprivation therapy (ADT). However, despite guideline recommendations, many patients undergo ADT alone or EBRT without ADT. We evaluated current trends in treatment of high risk prostate cancer and risk factors associated with non-standard of care treatment.
Methods: Men with high risk localized prostate cancer were retrospectively identified (cT3, PSA >20, Gleason 8-10, cN0M0) using the National Cancer Database (NCDB) between 2005-2015. Trends in treatment modalities were analyzed over this period. Multivariable logistic regression was performed to evaluate impact of clinical, racial, and socioeconomic factors on treatment method. Kaplan-Meier (KM) analysis was performed for overall survival (OS).
Results: A total of 149,343 patients with localized high risk prostate cancer were identified. 30,686 patients received non-standard of care treatment, categorized as EBRT without ADT or ADT alone. The percentage of men receiving non-standard of care treatment significantly decreased from 22.9% in 2005 to 18.7% in 2015 (P < 0.001). The percent of men receiving ADT alone significantly decreased over this interval (13.2% in 2005, 11.5% in 2015, P < 0.001), as did the percent of men receiving EBRT without ADT (9.8% in 2005, 7.2% in 2015, P < 0.001). On multivariable logistic regression, risk factors for receiving any non-standard of care treatment included increasing age (HR 1.06), black race (HR 1.41), uninsured status (HR 1.53), low income (HR 1.13), low volume centers (HR 1.13) and Charlson score of â‰¥2 (HR 1.17-1.26; all P < 0.001). On KM analysis, the 5 year OS for patients receiving ADT alone was 55.6%, compared to patients receiving definitive treatment with RP (92.7%) or EBRT+ADT (80.7%) (log-rank, P < 0.001).
Conclusions: Use of non-standard of care therapy, including EBRT without ADT or ADT alone, in the setting of localized high risk prostate cancer is decreasing but still accounts for approximately 20% of treatment. Disparities exist, as black race, lower income status, and low volume facilities are independent risk factors associated with receiving non-standard of care.