Colorectal cancer: molecular features and clinical opportunities.

Colorectal cancer is a heterogeneous disease. There are three main pathways to colorectal cancer: the chromosomal instability pathway, the CpG island methylator phenotype pathway and the pure microsatellite instability pathway. Each of these is characterised by specific pathological precursors, mechanisms of carcinogenesis and natural history. The molecular features of these pathways have been exploited clinically in the diagnosis, screening and management of patients and families with colorectal cancer. This review summarises recent developments in our understanding of colorectal carcinogenesis and examines the interface between scientific discovery and the clinical application of molecular techniques in inherited and sporadic colorectal cancer.