Slow to change.
Top Line: The data for active surveillance in Black men with low-risk prostate cancer is less than robust.
The Study: A large retrospective look at outcomes among nearly 5300 men receiving active surveillance for low risk prostate cancer within the VA health system. First off, on multivariate analysis, PSA velocity (average absolute rise per year) was associated with grade group progression and metastases more consistently than the absolute PSA value itself. Over a quarter of men were Black, and they experienced progression to higher grade group prostate cancer at a much lower “optimal” threshold of PSA velocity (0.44 ng/mL/year) than White men (1.18 ng/mL/year). Quick stats lesson: the optimal threshold was determined using maximally selected rank statistics—multiple stratifications of a continuous variable (in this case, PSA) into dichotomous groups, landing on a breakpoint that will keep the groups furthest apart in regard to the outcome (here, progression). Even with these drastically different thresholds, it still portended a high risk of progression for Black men. For example, the incidence of grade group 2 disease at 7 years was 61% for Black men with a PSA velocity >0.44 (versus 40% below threshold) and 55% for white men with a PSA velocity >1.18 (versus 33% below threshold). Progression to grade group 3 for Black men above (versus below) the threshold was 29% (versus 13%) and for White men was 35% (versus 13%). TBD: how incorporating race into medical algorithms would be received.
TBL: “These data warrant consideration of substituting PSA velocity for serial prostate biopsies in [active surveillance for low risk prostate cancer]...with grade progression occurring at lower PSA velocity values for African American patients.” | Nelson, JAMA Netw Open 2021