Clinical Analysis of the Colorectal Cohort within the Wales Cancer Biobank: A Study of Outcomes and Genetic Screening

Over the last 12 years, the Wales Cancer Biobank (WCB) has consented to more than 2000 patients with colorectal cancer (CRC). From these patients, clinical data has been collected and patients have been followed through their cancer journey. Clinical data from these patients have been analyzed to identify any correlation between disease grade and outcome. In a small cohort, consisting of 407 patients, WCB has performed genetic analysis on patient primary tumor samples, identifying and characterizing mutations in the KRAS, NRAS, BRAF, PIK3CA and TP53 genes. The majority of patients with CRC who were consented to WCB were male with a mean age of 69 years and received surgery as the primary treatment for their disease. Pathology and disease-free survival data confirmed worse prognoses associated with more advanced disease. Heterogeneity within the primary tumor was explored in a subgroup of patients. Analysis of the KRAS and TP53 genes confirmed that more than 40% of CRC patients who were tested, harbored a genetic mutation within these genes in their primary tumor. Due to the limited sample size tested, most mutations did not show significant differences in disease-free survival, however, mutation of the BRAF gene did show a decrease in the disease specific survival, in keeping with the published data. Analysis of the patients diagnosed with CRC within the Biobank has provided us with valuable information on the status of CRC disease and treatment within the Welsh population. Over 12 years of consenting, we have witnessed significant changes in the information that researchers are interested in when sourcing samples for translational research. The development of new drugs that are tailored to the genetics of a cancer is emerging and at WCB we are focusing our collections on samples and data that meet the needs of this ever-evolving field.