4EVER: Assessment of circulating tumor cells with a novel, filtration-based method, in a phase IIIb multicenter study for postmenopausal, HER2- negative, estrogen receptor-positive, advanced breast cancer patients.

Breast Cancer - HER2/ER
Session Type and Session Title: 
General Poster Session, Breast Cancer - HER2/ER
Abstract Number: 
J Clin Oncol 31, 2013 (suppl; abstr 591)
Peter A. Fasching, Walter Gumbrecht, Tanja N Fehm, Lothar Haeberle, Mathias Muth, Daniel Sickert, Michael Pugia, Katja Friedrich, Mark Matzas, Diana Lueftner, Matthias W. Beckmann, Peyman Hadji, Julia Kreuzeder, Michael P Lux, Wolfgang Janni, Andreas Schneeweiss, Erik Belleville, Thomas Decker, Eva-Maria Grischke, Hans Tesch; Department of Obstetrics and Gynecology, University Erlangen, Erlangen, Germany; Siemens AG; Corporate Technology, Erlangen, Germany; Department of Gynecology and Obstetrics, Duesseldorf, Germany; Department of Gynecology and Obstetrics, University Hospital Erlangen, Erlangen, Germany; Novartis Pharma GmbH, Nuremberg, Germany; Siemens AG; Healthcare Sector, Erlangen, Germany; Siemens Healthcare Diagnostics, Elkhart, IN; Siemens AG, Erlangen, Germany; Department of Hematology, Oncology, and Tumor Immunology, Charité University Medicine, Campus Benjamin Franklin, Berlin, Germany; University Hospital of Giessen and Marburg GmbH, Marburg, Marburg, Germany; Department of Obstetrics and Gynaecology, University Breast Centre for Franconia, Erlangen, Germany; Department of Gynecology and Obstetrics, University of Ulm, Ulm, Germany; National Center for Tumor Diseases, University of Heidelberg, Heidelberg, Germany; Clinsol Gmbh & Co Kg, Wuerzburg, Germany; Onkologie Ravensburg, Ravensburg, Germany; University of Tuebingen, Tuebingen, Germany; Onkologische Gemeinschaftspraxis am Bethanien-Krankenhaus, Frankfurt/Main, Germany

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Abstract Disclosures


Background: The presence of circulating tumor cells (CTCs) has been shown to be of prognostic relevance for patients with early and advanced breast cancer (BC). The usefulness of CTC assessments depends on accurate cell counts and corresponding analysis of molecular targets. The aim of this sub study was to assess the feasibility of a novel, integrated CTC platform for automated cellular protein and nucleic acid analysis in a prospective multi-center study. Methods: The German 4EVER study included patients with postmenopausal, metastastic, ER positive, HER2 negative BC, who progressed after therapy with a non-steroidal aromatase inhibitor and were treated with exemestane and the mTOR inhibitor everolimus. Baseline blood samples (TransFix vaccum tubes, Cytomark, Caltag Medsystems Ltd.) were used for CTC analysis and processed on the modified Versant kPCR Sample Prep system using 8µm pore size Whatman Nuclepore track-etched membranes (GE Healthcare Piscataway, NJ). After CTC capture, immunostaining was performed for Cytokeratin 8/18/19 and CD45. CTCs were detected by image analytics after fluorescence scanning microscopy using a dedicated software solution implemented by Siemens. The data is summarized and correlated with baseline clinical characteristics. Results: CTC counts and clinical data were available for 111 blood samples (91.7%). CTCs were found in 75 patients (67,6%), 13 patients having 1 CTC, 38 having 2-9 CTCs and 24 patients having 10 or more CTCs. In an exploratory analysis the presence of CTCs was correlated with baseline patient and tumor characteristics. There were no associations with primary TNM stage, hormone receptor status or tumor type. Conclusions: CTC assessment with this novel filtration based method was feasible in a multi-center study setting. The CTC positivity rate was within the expected range. The follow-up of this study will give first insights, how the CTC measures of this platform can be used as a prognostic tool. As this CTC assessment platform was developed to perform additional automated cellular protein and nucleic acid analysis, the usefulness might derive from these analytic tools as well. Clinical trial information: NCT01626222.