CLINICAL TRIAL Pathological complete response rates following different neoadjuvant chemotherapy regimens for operable breast cancer according to ER status, in two parallel, randomized phase II trials with an adaptive study design (ECTO II)

Sequential doxorubicin/paclitaxel (AT) followed by CMF treatment was shown to be an active neoadjuvant chemotherapy regimen in the first European Cooperative Trial in Operable Breast Cancer (ECTO I trial). The aim of the current study (ECTO II) is to assess the complete pathological response (pCR) rate following three different anthracycline and taxane-containing neoadjuvant chemotherapy regimens, with or without capecitabine (X). Patients with operable, invasive breast cancer [2.0 cm in diameter, were randomized to AT?CMF, AT?CMX or AC?TX regimens in two parallel, randomized, open-label, phase II trials (within a single study) in patients with estrogen receptor negative (ER-) and estrogen receptor positive (ER?) diseases, respectively. Exemestane was delivered concomitantly with neoadjuvant chemotherapy in ER? tumors. Achievement of pCR was more common in ERthan ER? women (45.3 vs. 10.4%). Capecitabine was only associated with a higher frequency of pCR in ER? patients receiving AT?CMX. Overall response rates (ORR) ranged V. Semiglazov NN Petrov Research Institute of Oncology, St. Petersburg, Russian Federation F. Gaion Ospedale Civile di Camposampiero, Camposampiero, Italy M. Bari Presidio Ospedaliero di Noale, Noale, Italy P. Morandi Ospedale S. Bortolo, Vicenza, Italy P. Valagussa Fondazione Michelangelo, Milan, Italy Present Address: M. Zambetti G. Luca (&) Fondazione Centro San Raffaele del Monte Tabor, Via Olgettina, 60, 20132 Milano, Italy e-mail: [email protected] Presented in part at the 2010 Breast Cancer Symposium, October 1–3, Suburban Washington, DC, USA. M. Zambetti E. De Benedictis G. Luca Fondazione IRCCS Istituto Nazionale Tumori, Milan, Italy M. Mansutti Ospedale Universitario Santa Maria della Misericordia, Udine, Italy P. Gomez Hospital General Vall d’Hebron, Barcelona, Spain A. Lluch Hospital Clı́nico Universitario de Valencia, Valencia, Spain C. Dittrich LBI-ACR & ACR-ITR VIEnna, Kaiser Franz Josef-Spital, Vienna, Austria C. Zamagni Ospedale Policlinico S.Orsola Malpighi, Bologna, Italy E. Ciruelos Hospital Universitario 12 de Octubre, Madrid, Spain L. Pavesi Fondazione Salvatore Maugeri, Pavia, Italy 123 Breast Cancer Res Treat DOI 10.1007/s10549-011-1660-6