Abstract 421P
Background
Triplet-chemotherapy (TC) with or without (w/o) bevacizumab (TC-B) or anti-EGFR (TC-E) is highly effective as first line treatment (1L) for metastatic colorectal cancer (mCRC). However, it remains unclear if adding targeted therapy (TT) to TC improves clinical outcomes and metastasis resection rates compared to TC alone.
Methods
In this retrospective multicenter study, all consecutive patients (pts) with mCRC who started TC w/o TT as 1L treatment between January 2014 and 2019 in 14 centers in France were enrolled. We aimed to describe efficacy and safety of TC w/o TT and to identify potential predictive factors.
Results
A total of 332 pts (46% TC, 44% TC-B and 10% TC-E) were enrolled (186 male, median age 59.6 yo [21-86], 305 synchronous metastases, 163 RAS-mutated and 54 BRAF-mutated). Primitive tumor resection rate was significantly different between the 3 groups (p=0.004). Primitive tumor localization was also significantly different with more rectal cancer in TC (40%), right colon in TC-B (41%) and left colon in TC-E (61%); p<0.001. BRAF mutations were more frequent in the TC-B group (29%) compared to TC (9%) and TC-E (3%); p<0.001. Median OS were 34.8, 26.7 and 34.0 months in the TC, TC-B and TC-E group, respectively (NS). Median PFS were 14.9, 12.1 and 12.8 months in the TC, TC-B and TC-E group, respectively (p=0.017). Metastasis resection rates were 47%, 36% and 49% in the TC, TC-B and TC-E groups, respectively. After adjusting for age, primitive tumor localization, number of metastasis and primitive tumor resection, OS and PFS did not differ in the 3 groups. In the sub-group analysis of BRAF-mutated pts, median OS were 17.9 and 13.6 months in the TC and TC–B group, respectively (NS). In a predictive multivariate analysis, RAS and BRAF mutations were associated with reduced OS while no association was observed on PFS. Grade 3-4 adverse events were experienced in 31% of pts.
Conclusions
Efficacy and safety results in this real-world study were in line with published trials. All treatment regimens seemed similarly effective when well adapted to the RAS status. In BRAF-mutated pts, the adjunction of anti-VEGF to TC does not show significant effect on this small population but needs to be evaluated in further prospective trials.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
AGEO (Association des Gastro-Entérologues Oncologues).
Funding
Has not received any funding.
Disclosure
C. Toullec: Financial Interests, Personal, Advisory Role, Advisory, consultancy, board: Merck Serono; Sanofi; MSD; BMS; Ipsen; Amgen; Servier. S. Philonenko: Financial Interests, Personal, Advisory Board: Servier. P. Artru: Financial Interests, Personal, Other, Honoraria: Bristol-Myers Squibb; Financial Interests, Personal, Advisory Board, Honoraria: Servier; Financial Interests, Personal, Advisory Board: Amgen; Baxter; Pierre Fabre; Roche. S. Pernot: Financial Interests, Personal, Invited Speaker: Amgen; Roche; Merck; KGaA; Servier; Sanofi; Pierre Fabre; AstraZeneca. T. Lecomte: Financial Interests, Personal, Advisory Board, Honoraria, travel: Amgen; Servier; Financial Interests, Personal, Advisory Board, Honoraria: Sanofi; Financial Interests, Personal, Advisory Board: Merck Serono. Y. Touchefeu: Non-Financial Interests, Personal, Invited Speaker: Bayer; AAA; Ipsen; Servier; Amgen; Roche; Novartis; Financial Interests, Personal, Advisory Board: Ipsen; Merck; Other, Personal and Institutional, Principal Investigator: Bayer; Roche; BMS; MSD; AstraZeneca; Beigen; Incyte. A. Turpin: Financial Interests, Personal, Expert Testimony: Amgen; Merck Serono; Mylan; Financial Interests, Personal, Advisory Board: Servier; AstraZeneca. J. Taieb: Financial Interests, Personal, Advisory Board: Amgen; Celgene; Lilly; Merck KgaA; MSD; Pierre Fabre; Roche; Servier; Sirtex Medical; Financial Interests, Personal, Speaker’s Bureau: Amgen; Lilly; Merck; MSD; Pierre Fabre; Roche/Genentech; Sanofi; Servier. C. Coutzac: Financial Interests, Personal, Advisory Board: Servier; Financial Interests, Personal, Other: Amgen; Bayer; Mundipharma; Roche. All other authors have declared no conflicts of interest.