A prospective study of the impact of the 21-gene recurrence score assay on treatment decisions in N-, ER+ early stage breast cancer patients
11008 Background: The Oncotype DX™ Recurrence Score (RS) assay predicts distant recurrence risk and benefit of chemotherapy (CT) in N-, ER+ breast cancer patients (pts). In February 2006, Clalit Health Services in Israel (CHS) was the first public health insurer to reimburse the assay outside the USA. Methods: CHS requires a pre-authorization form with data on biological parameters and specification of treatment (Rx) recommendation (1) before knowledge of RS and (2) the Rx planned according to each of 3 possible RS risk levels. For the first 200 reimbursed assays, we compared: (1) the Rx offered without RS knowledge, (2) the Rx the patient actually received after RS, and (3) the planned Rx stated on the form to be given according to the RS. Results: 200 pts. Median age: 57 yrs (34–81). RS: Low risk (RS<18), 37.5%; Intermediate (int) risk (RS 18–30), 44.5%; High risk (RS≥31), 18%. In 20 pts, Rx recommendations before RS were not specified. Before the RS, CT was offered in 106/180 (59%) and hormonal therapy (HT) in 74/180 (41%). In 71/180 pts (39%) the actual Rx changed from the recommendation before RS - CT to HT in 62 pts (low risk: 37, int risk: 21, high risk: 4) and HT to CT in 9 pts (int risk: 4, high risk: 5). Suggested therapy by RS was not specified in 19 pts. In 30/181 (17%) actual Rx differed from planned - CT to HT in 20 pts (int risk: 17, high risk: 3) and HT to CT in 10 pts (low risk: 4, int risk: 6). Conclusions: RS changed the treatment decision in a significant proportion of pts (39%), mostly from CT to HT. In 58% of pts originally offered CT, knowledge of RS changed the Rx to HT. 12% of pts originally offered HT were treated with CT. Rx decisions in intermediate RS are sometimes not obvious. In 26% of intermediate RS, final Rx differed from original plan; in these cases, patients’ preferences might have had a major impact on decision making. No significant financial relationships to disclose.