Utilizing the Oncotype DX Recurrence Score in the Adjuvant Treatment Management of Node-Positive, Early-Stage Breast Cancer Patients
Michaela T Nguyen, Zhengming Chen, Timothy D'Alfonso, Alexander Stessin, Himanshu Nagar, Mary Hayes, Sandra J Shin. Weill Cornell Medical Center, New York, NY; New York Presbyterian, Weill Cornell Medical Center, New York, NY
Background: The 21 gene-RT-PCR assay Oncotype DX (Genomic Health) stratifies patients into low, intermediate, and high risk groups for developing systemic disease recurrence. While this assay has been used in the adjuvant treatment planning of node-negative, ER/PR positive, HER-2 negative, early-stage breast cancer patients, clinicians have begun to order this test in clinically similar breast cancer patients who are node-positive. Recent studies have shown that the utilization of this assay in the setting of node-negative early-stage breast cancer has led to a decrease in adjuvant chemotherapy use in these patients. However, whether this trend is also true when utilized in node-positive breast cancer patients is unknown and represents the aim of the current study.
Design: 543 breast cancer patients that had Oncotype DX testing performed as part of their routine clinical care between 2005-2012 at a single large academic medical center were retrospectively identified. Age, tumor size, tumor grade, nodal status, ER/PR status, Her2neu status, Ki-67 index, Oncotype DX recurrence score (ODxRS), and treatment plan were obtained by electronic medical record for each patient. Fisher's exact test was performed to determine the association between ODxRS and the utilization of adjuvant chemotherapy.
Results: 42 of 543 (8%) patients had node-positive, ER/PR positive, HER-2 negative, early-stage breast cancer. Nodal positivity was defined as metastasis > 2mm in size. 23 of 42 (55%) patients did not receive adjuvant chemotherapy. Of these 23 patients, 16 had a low ODxRS while the remaining 7 had an intermediate ODxRS. 19 patients received adjuvant chemotherapy and of these, 8 had a low ODxRS, 8 had an intermediate ODxRS and 3 had a high ODxRS. No significant association was identified between ODxRX and adjuvant chemotherapy utilization (p=0.067).
Conclusions: When Oncotype DX testing is performed, the resulting ODxRS does not appear to significantly influence the adjuvant treatment management of this subset of patients.
Wednesday, March 6, 2013 9:30 AM
Poster Session V # 35, Wednesday Morning