Colorectal Cancer Brain Metastasis With Concomitant KRAS and BRAF Mutations: A Case Report

Colorectal cancer (CRC) brain metastasis (BM) is a rare but aggressive manifestation of the disease, with poor prognosis and limited treatment options. Although brain metastases are more commonly associated with primary tumors located in the lung, skin, and breast, their occurrence in colorectal cancer is uncommon. Genetic mutations are highly important in tumor progression, and mutations in KRAS and BRAF genes are key drivers in colorectal cancer. However, the concurrent presence of both mutations is exceedingly rare. This case report presents a unique instance of colorectal cancer brain metastasis harboring both KRAS and BRAF mutations, highlighting its clinical significance and therapeutic challenges. We present the case of a 62-year-old male patient diagnosed with brain metastasis (in the cerebellum and right parietal lobe) who presented to the hospital with neurological symptoms. He underwent a CT imaging investigation that revealed multiple tumors. Subsequent biopsies confirmed the diagnosis of brain metastasis, with histological characteristics consistent with colonic adenocarcinoma. Tests also revealed aberrant expression of both KRAS and BRAF mutations. This case highlights the importance of considering brain metastases in colorectal cancer patients due to their detrimental effects on prognosis and survival rates. Additionally, the simultaneous presence of BRAF and KRAS mutations, in this case, adds an extra layer of complexity and severity.