Abstract A082: ENACT: A randomized trial assessing the impact of the Oncotype DX Prostate Cancer Assay on treatment decision in a racially diverse population of men eligible for active surveillance

Abstract

Abstract The Oncotype DX Prostate Cancer Assay® (ODX), a 17-gene expression profile performed on biopsy tissue, has been validated for prediction of adverse pathology at surgery and 10-year risk of metastasis or death. The assay output provided to the patient and clinician is a predicted probability. While these studies confirm the ability of the assay to discriminate indolent from aggressive prostate cancer (PCa), the assay’s actual clinical utility, in terms of its impact on treatment choice and psychological factors, has not been determined. Moreover, the assay’s utility for African American (AA) men remains an important knowledge gap for programs aimed at reducing PCa disparities through judicious use of active surveillance (AS). ENACT (Engaging Newly Diagnosed Men About Cancer Treatment Options) is an ongoing randomized trial comparing standard National Comprehensive Cancer Network (NCCN) based treatment counseling plus ODX to NCCN-based counseling alone for a largely AA population of men eligible for AS. The primary aim is to quantify the effect of ODX on treatment, testing the hypothesis that the assay causes a net migration towards AS. Secondary aims measure effects on psychological metrics dealing with cancer-related anxiety, decision conflict, and decision regret. Completion of the trial is expected in Fall 2019. Patients are enrolled at the UI Hospital, Stroger-Cook County Hospital and the Jesse Brown VA Medical Center in Chicago. Eligibility criteria include: biopsy-proven PCa with NCCN risk level Very Low, Low or Low Intermediate, age ⇐ 76, and estimated life expectancy >10 years. Thus far, 201 patients have enrolled and 180 have completed all study visits. Randomization (stratified by race and NCCN risk) occurs at Visit 1, when patients receive their diagnosis and initial counseling, and treatment decision is finalized at Visit 2, 2-3 weeks later. At Visit 3, ≈4 weeks after the decision but before treatment, surveys capture information about decision conflict and changes from Visit 1 in perceived cancer-related risk/mood. At Visit 4, ≈4 months after treatment starts, final surveys capture data on regret and evaluation of the decision process. Additional surveys record treatment preference of the attending urologist before and after the final decision. The enrolled population thus far is 71% AA, 35% age <60, and 42% NCCN Very Low risk, 33% Low risk, and 25% Low Intermediate risk. Drop-out for the primary endpoint is <5%. The data analysis will explore potential effect modification by race, risk level, health literacy, marital status, and relative vs. absolute change in predicted risk. The unique design of the ENACT trial raises questions about the need to evaluate predictive biomarkers, which are decision support tools, based on their actual impact on decision quality, especially for patients affected by a racial disparity in outcomes. The advent of multiplex biomarkers that provide clinicians and patients with probabilities rather than binary results adds to the complexity and the urgency of this need. Citation Format: Adam B Murphy, Samuel Carbunaru, Michael Abern, Courtney MP Hollowell, Roohollah Sharifi, Peter H. Gann. ENACT: A randomized trial assessing the impact of the Oncotype DX Prostate Cancer Assay on treatment decision in a racially diverse population of men eligible for active surveillance [abstract]. In: Proceedings of the Twelfth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2019 Sep 20-23; San Francisco, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(6 Suppl_2):Abstract nr A082.