ASPO Abstracts
Comparative Effectiveness Analysis of Oncotype Dx Utilization on Chemotherapy Toxicity Morbidity in the North Carolina Medicaid Population
Category: Survivorship & Health Outcomes/Comparative Effectiveness Research
Conference Year: 2019
Abstract Body:
Purpose: The objective of this study is to quantify the impact of the 21-gene assay test,Oncotype Dx (ODX), on acute chemotherapy related adverse events (AE) in a Medicaid insuredpopulation of women with node-negative Estrogen-Receptor Positive (ER+)/ Human EpidermalGrowth Factor Negative(HER2-) breast cancer. Background: Gene expression profiling,including the 21-gene assay test ODX, was developed to predict which patients with earlystage ER+, HER2-, node-negative breast cancer are at highest risk of recurrence and benefit the most from using chemotherapy. The result of changes in chemotherapy useresulting from ODX testing on incidence of AE in a Medicaid population remainsunexplored.Methods: A decision tree analysis was conducted to estimate the number of AEassociated with ODX testing compared to usual care in two simulated cohorts of 5,000Medicaid insured women ages 18-65 with Stages I-II node negative, ER+, and HER2- breastcancer in the state of NC. The time horizon was breast cancer diagnosis to completion ofprimary treatment and the outcome of interest was severe AE defined as incidence ofneutropenia or anemia requiring red blood cell transfusion. Probability of receivingchemotherapy in the intervention arm was determined by ODX score distribution and in theusual care arm it was determined by stage and age of diagnosis. Chemotherapy data,toxicity, and recurrence score distributions inputs were derived from published literatureusing the Carolina Breast Cancer Study and North Carolina Medicaid Claims data.Sensitivity analyses were conducted to test variations in ecurrence score distributionsand chemotherapy receipt. Results: In the simulation where all women receive ODX testing,27.7% (n=1,388) of women received chemotherapy and 19.2% (n=962) had an AE. In the usualcare model 41.7% (n=2,086) of women received chemotherapy and 33.5% (n=1,676) experiencedan AE. Sensitivity analyses revealed that further reduction of chemotherapy use in thelow- and intermediate ODX risk groups for whom chemotherapy is not indicated, wouldincrease the benefit of testing implementation. Conclusion: Increased use of ODX for womenwith breast cancer in the NC Medicaid population could result in the reduction ofchemotherapy associated adverse events.
Keywords: Breast CancerMedicaidComparativeEffectivenessSurvivorshipOutcomes