487P - First-line (1-L) bevacizumab plus chemotherapy (Bev/CT) in colorectal cancer (CRC) patients with potentially resectable liver only (LM) or liver and lung metastases (LLM): KRAS mutation analysis of the non-interventional PICASSO study

Abstract

The management of pts with CRC and LM only evolves with the progress in liver surgery and improved activity of anti-tumor agents. Criteria for the definition of unresectable and potentially resectable LM may vary among onco-surgical physicians. PICASSO was designed to describe the outcomes and management of CRC pts with potentially resectable LM or LLM, and treated 1-L Bev/CT in real-life setting. PICASSO was a French prospective non-interventional cohort study. Eligible pts with potential conversion to resectability of initially unresectable LM or LLM were included consecutively and treated with 1-L Bev/CT. Planned pts follow-up was 36 months (mo). The primary endpoint was the rate of patients with no detectable metastatic disease (DMD) after 1-L Bev/CT with/without metastases resection (MR). The results according to KRAS mutational status are presented here. Out of the 205 evaluable patients (efficacy population), a total of 153 pts included in the PICASSO study had known KRAS status: 60.8% had wild-type status (WT) and 39.2% had a mutated status (MT). Mean age was 66 years (SD =10), 64% were men and 96% had ECOG 0/1. Overall, 73% had synchronous metastases. The rate of pts without DMD after 1st-line Bev/CT with/without MR was 51% in KRAS WT pts and 36% in KRAS MT pts. Median PFS was 10.6 mo [95%CI: 8.8; 12.9] and 11.0 mo [8.9; 13.2] in the KRAS WT and KRAS MT pts respectively. Median PFS in pts without DMD was 14.8 mo [11.7- 17.1] for KRAS WT pts and 16.0 mo [10.6; 24.4] for KRAS MT pts. Median OS was not reached (NR) for KRAS WT pts and was 29.8 mo [25.8; NR] for KRAS MT pts. OS rate at 36 mo was 51.1% [39.0; 62.0] for KRAS WT pts and 44.3% [30.0; 57.7] for KRAS MT pts. for KRAS WT and MT pts without DMD, the OS rate at 36 mo was 79.3% [60.8; 89.7] and 73.1% [46.8; 87.9], respectively. Bev safety in the total population was comparable to its well-known safety profile. In real-life setting, 51% and 36% of KRAS WT and MT CRC pts with potentially resectable LM or LLM had no DMD after 1sl-L Bev/CT. Median PFS and OS rate at 36 months were comparable in both KRAS subgroups.