Molecular and clinical registry of Chilean patients diagnosed with BRAF-mutated colorectal cancer

Background: In recent years, the epidemiological trend of colorectal cancer (CRC) in Chile has become increasingly concerning, particularly due to the high costs associated with managing advanced-stage disease, which places a significant strain on the national healthcare system. In 2012, 2,417 new CRC cases were reported across both sexes in Chile. However, current projections estimate a sharp rise to 5,914 new cases, corresponding to an incidence rate of 20.7 per 100,000 individuals. This study aims to register the presence of BRAF mutations in Chilean patients to better characterize the molecular epidemiology of CRC in the local population. BRAF mutations are associated with poor prognosis, with affected patients typically exhibiting a median overall survival (OS) of less than 12 months. Methods: We present a cohort study that included 23 Chilean patients newly diagnosed with CRC and recruited up to April 1, 2024. Patients with a history of another malignant neoplasm diagnosed within the previous three years were excluded. BRAF mutations were analyzed in all participants treated within the public and private healthcare systems in Santiago, Chile. Results: Despite the rising prevalence of CRC in Chile, the frequency and distribution of BRAF mutations in the local population are unknown. Median OS differed by sex, with female patients showing a shorter OS of 24 months compared to 75 months in male patients (P=0.16). When stratified by stage at diagnosis, patients with stage II–III disease demonstrated a markedly longer median OS of 134 months, whereas those with stage IV disease had a median OS of only 24 months (P=0.12; not significant). Conclusions: Establishing comprehensive records of the most prevalent BRAF mutations in Chilean patients with CRC is essential for advancing precision oncology research. This knowledge has the potential to transform clinical management strategies and enhance treatment outcomes and the quality of life of patients. Consequently, an accurate assessment of BRAF gene mutations tailored to the molecular and clinical characteristics of each patient is crucial for optimizing treatment outcomes.