Efficacy of pertuzumab in combination with trastuzumab and a taxane in first-line treatment for metastatic breast cancer (MBC): A multicenter, retrospective, observational study.

e12504Background: Pertuzumab (P) , Trastuzumab (T) and Docetaxel (D) is standard first-line treatment in patients (pts) with HER2 + metastatic breast cancer (MBC). This multicenter retrospetive observational study was performed to evaluate the activity of P and T in combination with D or Paclitaxel (Tx) in real world HER2 + MBC pts. Methods: We identified HER2 + MBC pts treated with P, T and D or Ptx optionally followed by P, T and endocrine therapy (ET) maintenance in hormone positive (HR+) BC, in 17 Italian cancer centres between 09/2012 and 08/2016. Overall Survival (OS) and Progression Free Survival (PFS) were calculated by the Kaplan-Meier product-limit method. Log-rank test was used to assess differences between subgroups. Results: 191 pts were included in our analysis. Pts characteristics: median age 54 years (range 29-80); PS 0 in 127 (67%) pts and PS 1 in 54 (28%); 107 (56%) had visceral metastases (mts), 23 (12%) only bone mts and 28 (15%) brain mts, 130 (68%) were ER/PgR +. 76 pts (40%) were me...