PT - JOURNAL ARTICLE AU - GAUCHEZ, ANNE-SOPHIE AU - COLONNA, MARC AU - BRAND, FRANÇOIS-XAVIER AU - RAVANEL, NADIA AU - PASQUIER, DOMINIQUE AU - PAYAN, RAOUL AU - MOUSSEAU, MIREILLE TI - Kinetics of HER2/neu ECD in 45 Patients Treated with Trastuzumab (Herceptin®) between January 2001 and June 2005 at the Grenoble University Hospital DP - 2009 May 01 TA - Anticancer Research PG - 1703--1707 VI - 29 IP - 5 4099 - http://ar.iiarjournals.org/content/29/5/1703.short 4100 - http://ar.iiarjournals.org/content/29/5/1703.full SO - Anticancer Res2009 May 01; 29 AB - The aim of this study was to evaluate the utility of HER2/neu ECD concentration as a marker of the efficacity of clinical response to Herceptin®. Patients and Methods: Iterative measurements of HER2/neu ECD (ELISA c-erbB2/c-neu Rapid Format Elisa kit QIA10™ Calbiochem®) concentrations in 45 patients treated with Herceptin® between January 2001 and June 2005 at the Grenoble University Hospital. Results: Changes in HER2/neu ECD concentrations were observed in 21 patients (47%). The baseline concentration was the concentration of circulating HER2/neu ECD before treatment with Herceptin®. In 15 patients, the mean baseline concentration was 52 ng mL-1 (extreme values 13-170), which normalized no later than at the time of the 3rd administration of Herceptin®. Nine patients (60%) were still alive 5 years later (p<0.05). For 6 patients, the mean baseline concentration was 800 ng mL-1 (extreme values 140-2000) which persisted and even increased during Herceptin® therapy; fewer than 25% were alive 30 months later (p<0.05). In the case of the 24 patients whose HER2/neu ECD concentration remained <5 ng mL-1, survival time was intermediate. Conclusion: The study confirmed the utility of HER2/neu ECD in predicting therapeutic response. However, as in the case of other circulating tumor markers, it is only useful when there is a variation in concentration. This marker should now be evaluated in multi-center studies covering a large number of homogeneous subjects.