New insights into the earliest stages of colorectal tumorigenesis

Introduction: Tumors in the large intestine have been postulated to arise via a stepwise accumulation of mutations, a process that takes up to 20 years. Recent advances in lineage tracing and DNA sequencing, however, are revealing new evolutionary models that better explain the vast amount of heterogeneity observed within and across colorectal tumors.Areas covered: A review of the literature supporting a novel model of colorectal tumor evolution...