Clinical utility of gene-expression profiling in women with early breast cancer: an overview of systematic reviews

Purpose: This overview systematically evaluates the clinical utility of using Oncotype DX and Mamma Print gene-expression profiling tests to direct treatment decisions in women with breast cancer. The findings are intended to inform an updated recommendation from the Evaluation of Genomic Applications in Practice and Prevention Working Group. Methods: Evidence reported in systematic reviews evaluating the clinical utility of Oncotype DX and Mamma Print, as well as the ability to predict treatment outcomes, change in treatment decisions, and cost-effectiveness, was qualitatively synthesized. Results: Five systematic reviews found no direct evidence of clinical utility for either test. Indirect evidence showed Oncotype DX was able to predict treatment effects of adjuvant chemotherapy, whereas no evidence of predictive value was found for Mamma Print. Both tests influenced a change in treatment recommendations in 21 to 74% of participants. The cost-effectiveness of Oncotype DX varied with the alternative compared. For Mamma Print, lack of evidence of the predictive value led to uncertainty in the cost-effectiveness. Conclusion: No studies were identified that provided direct evidence that using gene-expression profiling tests to direct treatment decisions improved outcomes in women with breast cancer. Three ongoing studies may provide direct evidence for determining the clinical utility of gene-expression profiling testing.