A phase II trial of the CDK4/6 inhibitor palbociclib (P) as single agent or in combination with the same endocrine therapy (ET) received prior to disease progression, in patients (pts) with hormone receptor positive (HR+) HER2 negative (HER2-) metastatic breast cancer (mBC) (TREnd trial).

Luca Malorni, Giuseppe Curigliano, Alessandro Marco Minisini, Saverio Cinieri, Carlo Tondini, Grazia Arpino, Lorenzo Pavesi, Angelo Martignetti, Carmen Criscitiello, Fabio Puglisi, Marta Pestrin, Giuseppina Sanna, Erica Moretti, Emanuela Risi, Chiara Biagioni, Luca Boni, Daniela Baldari, Marc E. Buyse, Laura Biganzoli, Angelo Di Leo

Sandro Pitigliani Medical Oncology Department, Hospital of Prato, Istituto Toscano Tumori, Prato, Italy
Instituto Europeo di Oncologia, Milano, Italy
Department of Oncology, University Hospital Udine, Udine, Italy
ASL Brindisi, Oncology Department, Brindisi, Italy
Ospedale Papa Giovanni XXIII, Bergamo, Italy
University of Naples Federico II, Naples, Italy
ICS Maugeri, Padua, Italy
Azienda USL Toscana Sud Est, Siena, Italy
Department of Medicine, University of Udine and Department of Oncology, University Hospital of Udine, Udine, Italy
Clinical Trial Coordinating Center, AOU Careggi, Istituto Toscano Tumori, Florence, Italy
University of Florence, Health Science Department, Firenze, Italy
International Drug Development Institute, Louvain-La-Neuve, Belgium