How was the gene panel for the Oncotype DX assay developed and validated?
The identification of the gene panel for the Oncotype DX assay started with an extensive analysis of the human genome. Following the identification of a large set of genes associated with breast cancer, three studies explored the expression of 250 genes in patient tumor samples that were obtained at the time of initial diagnosis. The results of these studies were analyzed and used to develop a 21-gene assay that incorporated the genes which consistently correlated with distant recurrence-free survival. This assay was then validated, using prospectively-defined endpoints, in an independent clinical study of over 650 patient tumor samples from the tamoxifen-alone arm of the landmark NSABP Study B-14.
