It has been a matter of controversy as to whether c-myc gene expression is activated in human hepatocellular carcinoma (HCC). We observed that the c-myc mRNA level in HCC was similar to that of the adjacent non-cancerous portion, as determined in freshly obtained specimens after a partial liver resection. However, the c-myc transcript was at a low level in non-cancerous tissue which was biopsied prior to surgery, whereas it was still at a high level in HCC obtained without performing hepatectomy. These results suggest that the high transcript level observed in the non-cancerous tissue from the excised liver relates to liver resection itself, and that the c-myc gene expression is enhanced in the HCC.