Can Oncotype DX testing be omitted in invasive breast cancer patients with clinicopathologic factors predicting very high pretest probability of a concordant result?

OBJECTIVE: To determine if clinicopathologic (CP) factors could identify patients at "very low" and/or "very high" pretest probability of a high Oncotype DX (ODX) score. METHODS: A retrospective analysis of all patients that had ODX testing 2008-2018 at a single institution. RESULTS: Of 215 patients, all 16 (7.4%) with "all high" risk CP factors had high ODX scores, and all 45 (20.9%) over age 50 with "all low" risk CP factors had ODX recommendations for no chemotherapy. CONCLUSIONS: Oncotype DX results did not change chemotherapy recommendations in those with "very low" or "very high" pretest probability of high ODX scores.