The incidence of allelic loss of the DCC locus was significantly greater for patients with liver metastasis that for patients who had no liver metastasis for more than 2 years (19/20:95% vs 2/5:40%, P < 0.05).
Loss of heterozygosity (LOH) and/or rearrangement at the TP53 and DCC loci were detected in all liver metastases (10 of 10 at TP53 and 19 of 19 at DCC), and were observed in 59% (10 of 17) at TP53 and 75% (18 of 24) at DCC respectively in the primary tumors.
In addition, all 4 specimens of colorectal cancer with liver metastasis showed the decreased expression level of DCC mRNA, suggesting that functional loss of DCC in cancerous tissues may play an important role in metastatic events.