RECOMMENDATIONS In addition to estrogen and progesterone receptors and human epidermal growth factor receptor 2 , the panel found sufficient evidence of clinical utility for the biomarker assays Oncotype DX , EndoPredict , PAM50 , Breast Cancer Index , and urokinase plasminogen activator and plasminogen activator inhibitor type 1 in specific subgroups of breast cancer .
No biomarker except for estrogen receptor , progesterone receptor , and human epidermal growth factor receptor 2 was found to guide choices of specific treatment regimens .
PURPOSE To provide recommendations on appropriate use of breast tumor biomarker assay results to guide decisions on adjuvant systemic therapy for women with early-stage invasive breast cancer .
Gene expression and benefit of chemotherapy in women with node-negative, estrogen receptor-positive breast cancer.
PURPOSE The 21-gene recurrence score ( RS ) assay quantifies the likelihood of distant recurrence in women with estrogen receptor-positive , lymph node-negative breast cancer treated with adjuvant tamoxifen .  The relationship between the RS and chemotherapy benefit is not known . METHODS The RS was measured in tumors from the tamoxifen-treated and tamoxifen plus chemotherapy-treated patients in the National Surgical Adjuvant Breast and Bowel Project ( NSABP ) B20 trial . Cox proportional hazards models were utilized to test for interaction between chemotherapy treatment and the RS . RESULTS A total of 651 patients were assessable ( 227 r and omly assigned to tamoxifen and 424 r and omly assigned to tamoxifen plus chemotherapy ) . The test for interaction between chemotherapy treatment and RS was statistically significant ( P = .038 ) . Patients with high-RS ( > or = 31 ) tumors ( ie , high risk of recurrence ) had a large benefit from  chemotherapy  ( relative risk , 0.26 ; 95 % CI , 0.13 to 0.53 ; absolute decrease in 10-year distant recurrence rate : mean , 27.6 % ; SE , 8.0 % ) . Patients with low-RS ( < 18 ) tumors derived minimal , if any , benefit from chemotherapy treatment ( relative risk , 1.31 ; 95 % CI , 0.46 to 3.78 ; absolute decrease in distant recurrence rate at 10 years : mean , -1.1 % ; SE , 2.2 % ) . Patients with intermediate-RS tumors did not appear to have a large benefit , but the uncertainty in the estimate can not exclude a clinical ly important benefit . CONCLUSION The RS assay not only quantifies the likelihood of breast cancer recurrence in women with node-negative , estrogen receptor-positive breast cancer , but also predicts the magnitude of  chemotherapy benefit
RECOMMENDATIONS In addition to estrogen and progesterone receptors and human epidermal growth factor receptor 2 , the panel found sufficient evidence of clinical utility for the biomarker assays Oncotype DX , EndoPredict , PAM50 , Breast Cancer Index , and urokinase plasminogen activator and plasminogen activator inhibitor type 1 in specific subgroups of breast cancer .
No biomarker except for estrogen receptor , progesterone receptor , and human epidermal growth factor receptor 2 was found to guide choices of specific treatment regimens .
PURPOSE To provide recommendations on appropriate use of breast tumor biomarker assay results to guide decisions on adjuvant systemic therapy for women with early-stage invasive breast cancer .