Background: Although CHAARTED trial suggested a survival advantage in de novo (DN) high volume (HV) mCSPC pts, the use of DOC is still debated according to the timing of either metastatic onset [relapsed (REL) vs DN] or disease burden [low volume (LV) vs HV]. In this view, it could be of interest to describe the real-world use of DOC. From 2014, ECHOS multicenter study is collecting real world data from mCSPC pts in Italy, where DOC was the only reimbursed agent until recently. Here, we present study results after first data lock at the end of 2021. Methods: We reviewed the clinical records of the mCSPC pts treated with DOC in 34 Italian Institutions. For each pt we recorded pre and post-DOC clinical history, baseline characteristics, treatment details and clinical outcomes. Results: We identified 568 pts [median age 66.5 yrs (range 43-85)]. Most of them were classified as having a DN/HV disease (78%): the remaining had a REL/LV (2.5%), a REL/HV (8.1%), and a DN/LV disease (11.5%). After a median follow-up of 22 mos, 389 pts experienced disease progression and 227 died. The survival outcomes according to the metastases timing and disease volume is reported in the table. Conclusions: Our real-world experience shows that DOC is proposed not only in DN/HV pts, but also in the other pts regardless of metastases timing and disease volume. The prognosis of DN/HV pts treated with DOC appears to be worse than in CHAARTED trial. These findings need to be confirmed by further analyses made on larger number of pts enrolled in the ECHOS trial.

In pts with DN/HV disease, baseline hemoglobin and lactate dehydrogenase levels had a prognostic value at the multivariate analysis.