The rare BRAF VK600-601E mutation as a possible indicator of poor prognosis in rectal carcinoma - A report of a case

Background: The BRAF V600E mutation is reportedly associated with inferior survival among colon cancer patients. Here we report a patient with rectal cancer who carried the novel BRAF mutation VK600-601E, which has analogous molecular functions to those of the conventional BRAF mutation V600E, and may have potential as a prognostic marker for colorectal cancer (CRC). Case presentation: The present 65-year-old male patient was diagnosed with recurrent rectal adenocarcinoma (stage II by AJCC TNM staging 7th edition) 14 months after surgery and was treated with modified FOLFOX6 (fluorouracil, leucovorin, and oxaliplatin), radiation, and FOLFIRI (fluorouracil, leucovorin, and irinotecan). The tumor progressed before further treatment could be initiated, resulting in death after 15 months. This survival period was similar to the median overall survival among patients with metastatic CRC and BRAF mutations who were treated with the FOLFIRI regimen with or without cetuximab. Conclusions: Thus, the BRAF VK600-601E mutation may lead to an aggressive clinical course in CRC patients suffering from rapid progression and potential resistance to multiple therapeutic modalities.