Evidence of Sex Difference in DNA Synthesis in Hepatocellular Carcinoma

To clarify sex differences in DNA synthesis in hepatocellular carcinoma (HCC), bromodeoxyuridine labeling indices (BrdU LI) of HCC cells included in tumor biopsy specimens from 12 consecutive male patients and from 5 consecutive female patients all with liver cirrhosis and HCC were examined using an in vitro labeling technique. The mean BrdU LI ± SE of HCC from male patients (7.7 ±0.8%) was significantly (P<0.05) higher than that from female patients (4.4± 1.0%). While 7 of the 12 male HCC patients belonged to the high DNA synthesis group (BrdU LI ≥7.0%), none of the 5 female HCC patients showed high DNA synthesis (P<0.05). We conclude that DNA synthesis in HCC was higher in males than in females.