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 .
Which patients benefit most from adjuvant aromatase inhibitors? Results using a composite measure of prognostic risk in the BIG 1-98 randomized trial.
BACKGROUND On average , aromatase inhibitors are better than tamoxifen when used as initial or sequential therapy for postmenopausal women with endocrine-responsive early breast cancer . Because there may be contraindications to their use based on side-effects or cost , we investigated subgroups in which aromatase inhibitors may be more or less important . PATIENTS AND METHODS Breast International Group 1 - 98 trial r and omized 6182 women among four groups comparing letrozole and tamoxifen with sequences of each agent ; 5177 ( 84 % ) had central ly confirmed estrogen receptor ( ER ) positivity . We assessed whether central ly determined ER , progesterone receptor ( PgR ) , human epidermal growth factor receptor 2 , and Ki-67 labeling index , alone or in combination with other prognostic features , predicted the magnitude of letrozole effectiveness compared with either sequence or tamoxifen monotherapy . RESULTS Individually , none of the markers significantly predicted differential treatment effects . Sub population treatment effect pattern plot analysis of a composite measure of prognostic risk revealed three patterns . Estimated 5-year disease-free survival  for letrozole monotherapy , letrozole→tamoxifen , tamoxifen→letrozole , and tamoxifen monotherapy were 96 % , 94 % , 93 % , and 94 % , respectively , for patients at lowest risk ; 90 % , 91 % , 93 % , and 86 % , respectively , for patients at intermediate risk ; and 80 % , 76 % , 74 % , and 69 % , respectively , for patients at highest risk . CONCLUSION A composite measure of risk informs treatment selection better than individual biomarkers and supports the choice of 5 years of letrozole for patients at highest risk for recurrence
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 .