Impact of BRAF and RAS mutations on first-line efficacy of FOLFIRI plus cetuximab versus FOLFIRI plus bevacizumab: analysis of the FIRE-3 (AIO KRK-0306) study.
Eur J Cancer
; 79: 50-60, 2017 07.
Article
em En
| MEDLINE
| ID: mdl-28463756
ABSTRACT
BACKGROUND:
RAS and BRAF mutations have been identified as negative prognostic factors in metastatic colorectal cancer. Efficacy of 5-fluorouracil, leucovorin, irinotecan (FOLFIRI) plus bevacizumab in patients with RAS-mutant tumours needs to be further evaluated. Whether to treat patients with BRAF-mutant tumours with either bevacizumab or anti-epidermal growth factor receptor (EGFR) antibodies remains unclear.METHODS:
Patients treated within the FIRE-3 trial were retrospectively tested for BRAF and RAS mutations using formalin fixated paraffin embedded (FFPE) tumour material applying pyrosequencing for KRAS and NRAS exon 2, 3 and 4 mutations as far as for BRAF mutations. Survival analysis was done using Kaplan-Meier estimation and differences were expressed using the log-rank test. Overall response rate (ORR) was compared using Fisher's exact test. Data from a central independent radiological response evaluation were used to calculate early tumour shrinkage (ETS) and depth of response (DpR).RESULTS:
Overall, 188 patients with RAS-mutant tumours and 48 with BRAF-mutant tumours were identified. In BRAF-mutant patients, ORR was numerically higher in the cetuximab versus the bevacizumab arm (52% versus 40%), while comparable results were achieved for progression-free survival (PFS; hazard ratio [HR] = 0.84, p = 0.56) and overall survival (OS; HR 0.79, p = 0.45). RAS mutation was associated with a trend towards lower ORR (37% versus 50.5%, p = 0.11) and shorter PFS (7.4 versus 9.7 months; HR 1.25; p = 0.14) in patients receiving FOLFIRI plus cetuximab versus bevacizumab, but OS was comparable (19.1 versus 20.1 months; HR 1.05; p = 0.73), respectively. ETS identified subgroups sensitive to cetuximab-based treatment in both BRAF- (9/17) and RAS-mutant (18/48) patients and was associated with significantly longer OS. DpR was comparable between both treatment arms in RAS- and BRAF-mutant patients, respectively.CONCLUSIONS:
In BRAF- and RAS-mutant patients, cetuximab- and bevacizumab-based treatment had comparable survival times. ETS represents an early parameter associated with the benefit from anti-EGFR, while this was not the case with vascular endothelial growth factor A blockade.Palavras-chave
Texto completo:
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Neoplasias Colorretais
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Protocolos de Quimioterapia Combinada Antineoplásica
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Proteínas Proto-Oncogênicas p21(ras)
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Proteínas Proto-Oncogênicas B-raf
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Mutação
Tipo de estudo:
Observational_studies
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Prognostic_studies
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Risk_factors_studies
Limite:
Aged
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Female
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Humans
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Male
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Middle aged
Idioma:
En
Revista:
Eur J Cancer
Ano de publicação:
2017
Tipo de documento:
Article