LAUSR

160Background: Circulating aberrations (copy number/point mutation] of androgen receptor (AR) as well as serum chromogranin A (CgA) have been associated to treatment response and clinical outcome in CRPC patients (pts) treated with abiraterone (abi)/enzalutamide(enza). Methods: We determined AR aberrations by digital PCR, Taqman and targeted-next generation sequencing on pre-treatment plasma from 169 CRPC pts treated with abi 1g/od (n = 96) and prednisone 5mg/bid or enza 160mg/od (n = 73) (Romanel, 2015; Salvi, 2015; Salvi, 2016). All pts were subdivided into 3 groups using receiver-operating characteristic (ROC) curves (Burgio, 2014; Conteduca, 2014) to evaluate properly the impact of CgA levels: serum CgA level was normal when 360(group C,n = 36). The primary endpoint was the correlation between AR aberrations and CgA level. The secondary endpoints were progress...