Gene expression profiling in clinical practice The impact of Oncotype DX and EndoPredict on decision making with increasing oncological work experience
20 September 2018 (online)
Estimating distant recurrence risk is still challenging. OncotypeDX as well as EndoPredict are two competing, gene expression-based tests predicting the likelihood of recurrent diseases. We analyzed the difference in oncological decision making with and without the knowledge of gene expression tests as a measure of clinical work experience.
This retrospective, monocentric study included 192 patients with G2, HR+, Her2- breast cancer between 2011 and 2015. All 192 patients received an OncotypeDX or EndoPredict analysis. A tumor board (TB) with knowledge of these OncotypeDX or EndoPredict scores served as baseline (Control group). This baseline was compared to the treatment decision (chemotherapy Yes/No) by oncologists with different experience levels who were not provided OncotypeDX or EndoPredict scores.
Within the EndoPredict group no difference between overall TB decision (chemotherapy Yes) 48.1% vs. 15+ years 39.2%, 5 – 15 years 39.2% and less than 5 years 50.6% group could be shown. Within the OncotypeDX subgroup we found some difference between overall TB decision (chemotherapy Yes) 35.3% and 15+ years 42.5%, 5 – 15 years 50.4% and less than 5 years 55.6% group. Here it seems that inexperience led to a significant increase in chemotherapy recommendation. For the Ki67> 25% subgroup analysis we found tumor board decisions at 50% (chemotherapy Yes) vs. 15+ years 80%, 5 – 15 years 100% and less than 5 years 100%.
This pilot study yielded interesting results. Although numbers are small, rendering a subgroup analysis mostly descriptive in nature, it seems that the value of gene expression profiling increases with decreasing oncological experience.