Progression-free survival (PFS) with maintenance treatment with bevacizumab (B) in patients with responding mCRC after first-line chemotherapy (CT) plus B.

612 Background: Maintenance treatment with B is considered an option for mCRC pts in responding pts after a first line CT + B, but few data are available on its real benefit on PFS. Methods: We collected data from a cohort of mCRC pts consecutively treated in five oncologic centers of Lazio. One-hundred-ninety-nine mCRC pts treated with first line CT + B achieving a response [partial (PR) or complete (CR)] or a stable disease (SD) were considered eligible, 117 pts had received B maintenance (BM) whereas 82 did not (noBM). The two groups were homogeneous for main characteristics. First-line therapy in the BM vs noBM group included FOLFIRI regimen (96 vs 59 pts), FOLFOX (18 vs 22 pts) and FUFA (3 vs 1 pts). K-ras status was analyzed in 115 pts with an higher percentage of wild-type (wt) in the BM group (65 vs 50 pts, p= 0.04). A CR or PR have been achieved in 65% of pts in the BM group and 61% of noBM group, while a SD was observed in 35% and 39% of pts respectively for the BM and noBM group. The median num...