Trends in treatments for prostate cancer in the United States, 2010-2015

Although annual mortality trends for prostate cancer were stabilized in recent years, understanding the exact treatment changes is necessary for optimal management. Utilization of not-otherwise specified (NOS) treatments for prostate cancer was unclear. Thus, this study aimed to analyze trends in treatment for prostate cancer in the U.S. from 2010 to 2015 and examine whether the treatment for the prostate cancer in the U.S. is compliant with clinical practice guidelines. Using joinpoint regression models, we examined trends in the rate and proportion of age-standardized utilization (ASUR and ASUP) of treatments for prostate cancer diagnosed during 2010-2015 in the U.S. based on the data from the Surveillance, Epidemiology, and End Results (SEER, 2018 data-release, with linkage to active surveillance/watchful waiting [AS/WW]) cancer registry program. Among 316,690 men with prostate cancer diagnosed during 2010-2015, ASUR and ASUP for radical prostatectomy, radiotherapy, AS/WW and NOS treatment were 32.7, 34.4, 10.0 and 40.1 per 100,000, and 27.9%, 29.3%, 8.5% and 34.2%, respectively. Trends in the overall ASUR for prostate cancer treatments differed by cancer risk group, patients' age, race/ethnicity, Gleason score, insurance status, and the average education level, average poverty-level and foreign-born person percentage of the patient's residence-county, but not by rural-urban continuum or region. ASUP of radical prostatectomy decreased from 9.8% in 2010 to 4.8% in 2015 (annual percent change [APC] = -12.0%, 95% CI, -15.9 to -7.9%), and the decrease was observed in all different risk groups. ASUP of AS/WW increased from 16.4% in 2010 to 30.2% in 2013 (APC = 22.7%, 95% CI, 4.6 to 44.0%) and then remained stable through 2013 to 2015 (APC = 1.9%, 95% CI, -24.1 to 36.9%). The increasing tendency of AS/WW only occurred in the low-risk and intermediate-risk groups. The ASUP of NOS treatment has increased from 32.3% in 2010 to 36.8% in 2015 (P<0.01). In conclusion, ASUR and ASUP for prostate cancer treatments, including NOS treatment, had changed during 2010-2015. Their trends appeared to differ by cancer risk-group, age, race/ethnicity, Gleason score and socioeconomic factors. Future studies are warranted to understand the impacts of upward trends in ASUP of NOS treatments and AS/WW on patient survival and prostate cancer mortality.