#3113 Background: The 21-gene Recurrence Score (RS) assay has been validated to quantify the risk of distant recurrence in tamoxifen treated patients (pts) in node negative, estrogen receptor positive breast cancer (BC) and predict magnitude of chemotherapy benefit. We previously showed that the RS impacted medical oncologists (MOs) and pts adjuvant treatment decision making, decreased situational anxiety and decisional conflict, and improved pt satisfaction regarding adjuvant treatment decisions. Herein, we present the 12 month post-RS data for MOs and pts.
 Material and Methods: MOs stated their treatment recommendation and confidence in it pre- and post-RS assay, and completed a 12 month questionnaire. Pts completed 4 questionnaires pre- and immediately post-RS, and 12 months later: 1) Patient Treatment Decision Making Questionnaire; 2) Decisional Conflict Scale (DCS); 3) State-Trait Anxiety Inventory; and 4) Functional Assessment of Cancer Therapy-Breast. Frequency distributions, means and standard deviations summarized data. Paired samples t-tests and repeated measures ANOVA assessed quality of life, decisional conflict and anxiety.
 Results: Accrual goal was met with 89 evaluable pts. 16/17 (94%) MOs and 67 pts (75%) completed the 12 month assessment. There were no breast cancer recurrences recorded at 12 months. The majority of MOs reported increase confidence in their treatment recommendation (n=15, 93.8%), felt the RS provided additional information (n=15, 93.8%), and influenced treatment recommendation (n=14, 87.6%). Results from the DCS immediately post-RS indicate reduced conflict over treatment (p <.0001), greater pt satisfaction, and increased confidence with choice of adjuvant therapy (p <.0001). Pts reported they were glad they took the test 12 months later (n=62, 92.5%), found results easy to understand (n=60, 89.6%), and the test influenced treatment decision (n=54, 80.6%). Sixty four (95.5%) were satisfied with their adjuvant decision. State anxiety decreased over the year (mean 38.9 to 34.0, p. = 007), the most significant decline occurred pre- to immediately post-RS. Quality of life remained constant.
 Conclusions: The RS assay has an immediate and enduring impact on MOs and pts adjuvant decision making. MOs and pts report continued confidence and satisfaction with the assay. Pts had a decrease in decisional conflict right after the test, situational anxiety declined over the next 12 months and quality of life remained stable.
 Investigator initiated trial supported by an unrestricted clinical trials grant from Genomic Health Inc. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 3113.