TY - BOOK AU - Swain, Sandra M TI - Biomarker analyses in CLEOPATRA: a phase III, placebo-controlled study of pertuzumab in human epidermal growth factor receptor 2-positive, first-line metastatic breast cancer SN - 0732-183X PY - 2014/// KW - *Antibodies, Monoclonal, Humanized/tu [Therapeutic Use] KW - *Antineoplastic Agents/tu [Therapeutic Use] KW - *Breast Neoplasms/dt [Drug Therapy] KW - *Receptor, ErbB-2/an [Analysis] KW - *Tumor Markers, Biological/an [Analysis] KW - Breast Neoplasms/bl [Blood] KW - Breast Neoplasms/ch [Chemistry] KW - Breast Neoplasms/mo [Mortality] KW - Double-Blind Method KW - Female KW - Humans KW - Mutation KW - Neoplasm Metastasis KW - Phosphatidylinositol 3-Kinases/ge [Genetics] KW - Prognosis KW - Prospective Studies KW - Receptors, Estrogen/an [Analysis] KW - Washington Cancer Institute KW - Clinical Trial, Phase III KW - Journal Article KW - Randomized Controlled Trial KW - Research Support, Non-U.S. Gov't N1 - Available online from MWHC library: 1999 - present, Available in print through MWHC library: 1999 - 2008 N2 - CONCLUSION: Through comprehensive prospective analyses, CLEOPATRA biomarker data demonstrate that HER2 is the only marker suited for patient selection for the trastuzumab plus pertuzumab-based regimen in HER2-positive metastatic breast cancer. HER2, HER3, and PIK3CA were relevant prognostic factors.Copyright � 2014 by American Society of Clinical Oncology; PATIENTS AND METHODS: Mandatory tumor and serum samples were collected (N = 808; 58% to 99.8% were assessable), and amphiregulin, betacellulin, epidermal growth factor (EGF), transforming growth factor alpha, EGF receptor, HER2, HER3, insulin-like growth factor 1 receptor, PTEN, phosphorylated AKT, PIK3CA, CMYC, serum HER2 extracellular domain (sHER2), and FCR were assessed using appropriate assays. Two types of correlations were investigated using univariable Cox regression: predictive effects (qualitative association of biomarkers with pertuzumab progression-free survival [PFS] benefit) and prognostic effects independent of treatment arm (relationship of each biomarker to clinical outcome in both arms pooled); PURPOSE: To explore the prognostic and/or predictive value of human epidermal growth factor receptor 2 (HER2) pathway-related biomarkers in the phase III CLEOPATRA study of pertuzumab plus trastuzumab plus docetaxel versus placebo plus trastuzumab plus docetaxel as first-line treatment for patients with HER2-positive metastatic breast cancer; RESULTS: Pertuzumab consistently showed a PFS benefit, independent of biomarker subgroups (hazard ratio < 1.0), including estrogen receptor-negative and -positive subgroups. High HER2 protein, high HER2 and HER3 mRNA levels, wild-type PIK3CA, and low sHER2 showed a significantly better prognosis (P < .05). PIK3CA showed the greatest prognostic effect, with longer median PFS for patients whose tumors expressed wild-type versus mutated PIK3CA in both the control (13.8 v 8.6 months) and pertuzumab groups (21.8 v 12.5 months) UR - http://dx.doi.org/10.1200/JCO.2013.54.5384 ER -