 Approximately 70% of primary colorectal cancers display LOH in this region, and the percentage increases when comparing early to advanced cancers.This increase in DCC loss in advanced cancer may indicate that DCC loss is more important to tumour progression than tumour formation.However, region 18q is not the location of DCC alone, and many studies are in conflict when reporting whether 18q LOH is attributable to DCC or other tumour suppressor candidates in the neighbouring areas.