A Rare BRAF Fusion in Advanced Rectal Cancer Treated with Anti-Epidermal Growth Factor Receptor Therapy

Recently, v-raf murine sarcoma viral oncogene homologue B (BRAF) fusions have been identified in multiple cancer types using comprehensive genomic profiling (CGP) assays. BRAF fusions are extremely rare, occurring in <0.5% of patients with metastatic colorectal cancer (mCRC). Until now, the...

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Bibliographic Details
Main Authors: Hiroko Hasegawa, Masaaki Miyo, Kiyoshi Mori, Masayuki Mano, Hisashi Ishida, Eiji Mita
Format: Article
Language:English
Published: Karger Publishers 2021-06-01
Series:Case Reports in Oncology
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Online Access:https://www.karger.com/Article/FullText/517007
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Summary:Recently, v-raf murine sarcoma viral oncogene homologue B (BRAF) fusions have been identified in multiple cancer types using comprehensive genomic profiling (CGP) assays. BRAF fusions are extremely rare, occurring in <0.5% of patients with metastatic colorectal cancer (mCRC). Until now, there is no standard treatment for mCRC with BRAF fusions. Here, we report a recurrent colorectal cancer case that harbored an EXOC4-BRAF fusion. A 40-year-old female patient with a 2-year history of type 2 diabetes was diagnosed with pathologically confirmed stage IV rectal adenocarcinoma with liver metastasis. She underwent R0 resection after neoadjuvant therapy; however, her disease recurred at multiple metastatic sites (lymph nodes, ovary, and peritoneal gland). A rectal cancer surgical specimen was submitted for CGP (Foundation One) to identify potential targets to develop treatment strategies. An EXOC4-BRAF fusion was identified, and she achieved partial response to FOLFOX + panitumumab which is a fully human antibody directed against epidermal growth factor receptor. No EXOC4-BRAF fusions in colorectal cancer cases have been reported to date. Further studies investigating molecular mechanisms and novel targeted therapy approaches are required.
ISSN:1662-6575