Long term response on Regorafenib in non-V600E BRAF mutated colon cancer: a case report

Eduard Callebout,Liesbeth Ferdinande,Stephanie Laurent,Kathleen B M Claes,Suzane Moura Ribeiro,Joni Van Der Meulen,Marc De Man,Karen P Geboes

doi:10.1186/s12885-019-5763-5

Abstract

BackgroundNon-V600E BRAF mutated colorectal cancer (CRC) is a rare disease entity with specific clinical features. These tumors are less likely to have microsatellite instability than CRC with a V600E BRAF mutation and often harbor a KRAS or NRAS mutation. Notably, median overall survival is longer than in wild-type BRAF CRC. Little is known about treatment possibilities in these patients.Case presentationWe present the case of a 59 year old patient with a rare mutation in BRAF codon 594, who progressed rapidly on all classical therapies but experienced a clear and long lasting response on treatment with Regorafenib.ConclusionLittle is known about therapies that can be effective in the rare non-V600E BRAF mutated CRCs. We present a patient who had a definite response to treatment with Regorafenib. There are no predictive markers that define a subset of CRC patients who benefit most from Regorafenib. The specific features of this non-V600E BRAF mutated CRC may be relevant in the exploration of predictive biomarkers for the efficacy of Regorafenib.

Highlights

Non-V600E v-raf murine sarcoma viral oncogene homolog B1 (BRAF) mutated colorectal cancer (CRC) is a rare disease entity with specific clinical features
Patients with Non-V600E BRAF mutated CRC are rare and little is known about treatment possibilities in these patients
We present a case of a patient with a specific mutation, c.1781A > G (p.(Asp594Gly)) in exon 15, with a clear response and a long benefit on treatment with Regorafenib

Summary

Introduction

Non-V600E BRAF mutated colorectal cancer (CRC) is a rare disease entity with specific clinical features. Belgium Full list of author information is available at the end of the article patients, which accounts for 22% of all BRAF mutations. Non-V600E BRAF mutated tumors differ in molecular and pathological characteristics as well as phenotypically [3, 4].

Results

Conclusion