%0 Journal Article
%T Time-Dependent Prognostic Impact of Circulating Tumor Cells Detection in Non-Metastatic Breast Cancer: 70-Month Analysis of the REMAGUS02 Study
%A Fran£¿ois-Cl¨¦ment Bidard
%A Lisa Belin
%A Suzette Delaloge
%A Florence Lerebours
%A Charlotte Ngo
%A Fabien Reyal
%A S¨¦verine Alran
%A Sylvie Giacchetti
%A Michel Marty
%A Ronald Lebofsky
%A Jean-Yves Pierga
%J International Journal of Breast Cancer
%D 2013
%I Hindawi Publishing Corporation
%R 10.1155/2013/130470
%X Introduction. In non-metastatic breast cancer patients, the REMAGUS02 neoadjuvant study was the first to report a significant impact of circulating tumor cells (CTCs) detection by the CellSearch system on the distant metastasis-free survival (DMFS) and overall survival (OS) endpoints. However, these results were only reported after a short follow-up. Here, we present the updated data, with a longer follow-up. Material and Methods. CTC count was performed before and after neoadjuvant chemotherapy in 118 patients and correlated to survival. Results. CTC count results were available before and/or after neoadjuvant chemotherapy in 115 patients. After a median follow-up of 70 months, detection of ¡İ1 CTC/7.5£¿mL before chemotherapy ( ) was significantly associated with DMFS ( ) and OS ( ), whereas postchemotherapy CTC detection ( ) had no significant impact. In multivariable analysis, prechemotherapy CTC and triple negative phenotype were the two independent prognostic factors for survival. We observed that the CTC impact is most significant during the first three years of follow-up. Discussion. We confirm that the detection of CTC is independently associated with a significantly worse outcome, but mainly during the first 3-4 years of follow-up. No prognostic impact is seen in patients who are still relapse-free at this moment. 1. Introduction Over the past decade, two opportunities have been created to study the hematogenous metastatic process in breast cancer patients: disseminated tumor cells (DTCs), which are detected in the bone marrow, and circulating tumors cells (CTCs), which are detected in the blood [1]. In non-metastatic breast cancer patients, a pooled analysis published in 2005 established that bone marrow DTC detection is an independent prognostic factor of later metastatic relapse [2]. Survival data obtained in this analysis, as well as in other studies [3, 4], were based on a long follow-up, generally of more than 5 years, and suggested that the prognostic impact of DTC (i.e., hazard ratio of relapse or death) was rather constant over time in the population at risk. This finding is consistent with the fact that DTCs are quiescent tumor cells and can stay in G0 phase for many years, before metastatic growth. In contrast, CTCs have been mostly studied in metastatic breast cancer patients, with numerous studies reporting that elevated CTC count, either at baseline or during or after treatment, is associated with a worse outcome [5¨C11]. The FDA-approved CellSearch detection system is currently the most frequently used system in the clinic for CTC
%U http://www.hindawi.com/journals/ijbc/2013/130470/