The comparison study assessed 465 patients with hormone receptor-positive breast cancer from a previous Eastern Cooperative Oncology Group (ECOG) study, computing both the Adjuvant Online risk estimate and Oncotype DX Recurrence Score result for each patient. The study found that the Recurrence Score result was a highly significant predictor of recurrence in both node-negative disease (p=0.0007) and node-positive disease (p=0.0004). In addition, a low Recurrence Score result predicted a low likelihood of recurrence regardless of nodal status.
Oncotype DX is said to measure the expression of 21 genes of an individual tumor to generate a Recurrence Score result that quantifies the likelihood of recurrence and the magnitude of chemotherapy benefit for a large portion of early-stage breast cancer patients.
Steven Shak, chief medical officer of Genomic Health, said: “These results, combined with updated ASCO treatment guidelines now recommending Oncotype DX, clearly demonstrate that Oncotype DX provides critical information for breast cancer treatment planning that is not apparent by examination of clinical variables alone.”