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 .
Impact of PTEN protein expression on benefit from adjuvant trastuzumab in early-stage human epidermal growth factor receptor 2-positive breast cancer in the North Central Cancer Treatment Group N9831 trial.
PURPOSE It has been suggested that PTEN , a negative regulator of PI3K/AKT signaling , is involved in tumor sensitivity to trastuzumab . We investigated the association between tumor PTEN protein expression and disease-free survival ( DFS ) of patients r and omly assigned to receive chemotherapy alone ( arm A ) or chemotherapy with sequential ( arm B ) or concurrent trastuzumab ( arm C ) in the phase III early-stage human epidermal growth factor receptor 2 ( HER2 ) -positive trial-North Central Cancer Treatment Group ( NCCTG ) N9831 . PATIENTS AND METHODS The intensity and percentage of invasive cells with cytoplasmic PTEN staining were determined in tissue microarray sections containing three cores per block ( n = 1,286 ) or in whole tissue sections ( WS ; n = 516 ) by using st and ard immunohistochemistry ( 138G6 monoclonal antibody ) . Tumors were considered positive for PTEN ( PTEN-positive ) if any core or WS had any invasive cells with ≥ 1 + staining . Median follow-up was 6.0 years . RESULTS Of 1,802 patients included in this analysis ( of 3,505 patients registered to N9831 ) , 1,342 ( 74 % ) had PTEN-positive tumors . PTEN positivity was associated with hormone receptor negativity ( χ(2 ) P < .001 ) and nodal positivity ( χ(2 ) P = .04 ) . PTEN did not have an impact on DFS within the various arms . Comparing DFS of arm C to arm A , patients with PTEN-positive and PTEN-negative tumors had hazard ratios ( HRs ) of 0.65 ( P = .003 ) and 0.47 ( P = .005 ) , respectively ( interaction P = .16 ) . For arm B versus arm A , patients with PTEN-positive and PTEN-negative tumors had HRs of 0.70 ( P = .009 ) and 0.85 ( P = .44 ) , respectively ( interaction P = .47 ) . CONCLUSION In contrast to selected pre clinical and limited clinical studies suggesting a decrease in trastuzumab sensitivity in patients with PTEN-negative tumors , our data show benefit of adjuvant trastuzumab for patients with HER2-positive breast cancer , independent of tumor PTEN status
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 .