The Genomic Prostate Score (GPS), performed on biopsy tissue, predicts adverse outcome in prostate cancer (PCa) and has shown promise for improving patient selection for active surveillance (AS). However, its impact on treatment choice in high-risk populations of African Americans is largely unknown and, in general, the effect of the GPS on this difficult decision has not been evaluated in randomized trials.
Two hundred men with National Comprehensive Cancer Network very low to low-intermediate PCa from three Chicago hospitals (70% Black, 16% college graduates) were randomly assigned at diagnosis to standard counseling with or without a 12-gene GPS assay. The primary end point was treatment choice at a second postdiagnosis visit. The proportion of patients choosing AS was compared, and multivariable modeling was used to estimate the effects of various factors on AS acceptance.
AS acceptance was high overall, although marginally lower in the intervention group (77% v 88%; P = .067), and lower still when men with inadequate specimens were excluded (P = .029). Men with lower health literacy who received a GPS were seven-fold less likely to choose AS compared with controls, whereas no difference was seen in men with higher health literacy (Pinteraction = .022). Among men with low-intermediate risk, 69% had GPS values consistent with unfavorable intermediate or high-risk cancer. AS choice was also independently associated with a family history of PCa and having health insurance.
In contrast to other studies, the net effect of the GPS was to move patients away from AS, primarily among men with low health literacy. These findings have implications for our understanding of how prognostic molecular assays that generate probabilities of poor outcome can affect treatment decisions in diverse clinical populations.
Journal of clinical oncology : official journal of the American Society of Clinical Oncology. 2021 Apr 09 [Epub ahead of print]
Adam B Murphy, Michael R Abern, Li Liu, Heidy Wang, Courtney M P Hollowell, Roohollah Sharifi, Patricia Vidal, Andre Kajdacsy-Balla, Marin Sekosan, Karen Ferrer, Shoujin Wu, Marlene Gallegos, Patrice King-Lee, Lisa K Sharp, Carol E Ferrans, Peter H Gann
Department of Urology, Northwestern University, Chicago, IL., Department of Urology, University of Illinois at Chicago, Chicago, IL., Division of Epidemiology and Biostatistics, University of Illinois at Chicago, Chicago, IL., Division of Urology, Cook County Health and Hospital System, Chicago, IL., Department of Urology, Jesse Brown VA Medical Center, Chicago, IL., Department of Pathology, University of Illinois at Chicago, Chicago, IL., Department of Pathology, Cook County Health and Hospital System, Chicago, IL., Pathology and Laboratory Services, Jesse Brown VA Medical Center, Chicago, IL., Institute for Health Research and Policy, University of Illinois at Chicago, Chicago, IL., Department of Biobehavioral Nursing Science, University of Illinois at Chicago, Chicago, IL.