DURHAM, NC—Despite its status as the most common cancer in American men, prostate cancer remains significantly understudied in terms of its epidemiology. Previous research has shown a higher risk for prostate cancer overall among Black men, but whether that difference persists in advanced prostate cancer has not been extensively researched.
As the largest healthcare system in the country and the provider of prostate cancer services to the most men in the United States, the VA has a significant interest in understanding the incidence of various forms of advance prostate cancer and which veterans are at greatest risk for each type. Consequently, researchers led by Shannon Stock, PhD, of the Durham, NC, VA HealthCare System (VAHCS) conducted a study to determine the incidence rates of non-metastatic hormone-sensitive prostate cancer (nmHSPC), de novo metastatic hormone-sensitive prostate cancer (mHSPC), non-metastatic castration-resistant prostate cancer (nmCRPC) and metastatic castration-resistant prostate cancer (mCRPC) in Black and White veterans.
Their retrospective study examined the health records of veterans who were active users of the VA’s health services between 2012 and 2019 and were diagnosed with prostate cancer. The team calculated standardized annual incidence rates for each type of advance prostate cancer and rate ratios for race using U.S. Census age and race-specific population estimates.
The incidence rates in 2019 for nmHSPC were 453.0 and 205.3 and 33.7 and 15.1 for mHSPC, for Black and White men, respectively. For castration-resistant prostate cancer, the incidence rate for the non-metastatic form were 23.4 for Black men and 8.5 for white men, while the metastatic type of CRPC had incidence rates of 49.1 among Black men and 19.4 among White men.
Incidence rates varied between years of the study, but the rate ratios remained consistent, with the rate ratio significantly higher for Black vs. White men for all types of advanced prostate cancer (all p < 0.0001). The rate ratio for nmHSPC and mHSPC was 2.2, while for nm CRPC it was 2.8 and for mCRPC it was 2.5.
Trends in incident rates (IRs) remained consistent over the study period by race as well. Only the incidence rate for metastatic hormone-sensitive prostate cancer trended upward throughout the study, with an annual percent change of 10.6%.
“Our findings provide novel and comprehensive data on IRs across prostate cancer clinical states by race and over time within the VAHCS,” the research team said. “Despite the VAHCS providing an environment of relatively equal access to care, Black men experience a disproportionate burden of PC with IRs over 2-fold higher for all clinical states relative to White men. This highlights that resolving access to care alone is unlikely to fully eliminate PC racial differences and that there are other multifactorial issues to address.”
The investigators also noted that the drop in nmHSPC from 2012 to 2016 and the rise in following years “are consistent with the timing of the 2012 US Preventive Services Task Force guidelines advising against [prostate-specific antigen] screening and the subsequent draft reversal in 2017.”
- Stock SR, Burns MT, Waller J, De Hoedt AM, Ghate S, Kim J, Polascik TJ, Shui IM, Freedland SJ. Epidemiology and racial differences of prostate cancer clinical states. J Clin Oncol 40, 2022 (suppl 16; abstr 5062)