Multidrug resistance in the standardized treatment of colon cancer harboring a rare fibrosarcoma B-type (BRAF) p.N581I mutation: a case report

BRAF non-V600 mutations are a distinct molecular subset of colorectal cancer (CRC) that has little to no clinical similarity the V600 mutations. It is generally considered correlate with better survival CRC patients. In this report, we present an unusual case midlife female patient who was initially diagnosed stage IIIC colon cancer, and multiple metastases were found 25 months after radical surgery. Next-generation sequencing (NGS) revealed p.N581I (c.1742A>T) mutation. She received chemotherapy, targeted therapy, immunotherapy. However, disease progressed rapidly rare metastasis bone cerebellum. This highlights mutations, such as mutant, may lead resistance epidermal growth factor receptor (EGFR) inhibitors result in rapid course cancer. The role mutation demands more attention.