Major hepatic resection may suppress the growth of tumours remaining in the residual liver

Little is known as to how hepatectomy is associated with the growth of hepa tic tumours, which may reside in the remaining liver after curative resecti on for hepatocellular carcinoma. Using an intra-hepatic tumour implantation model in rats, the effects of hepatectomy on tumour growth in the remainin g liver were investigated. On post-operative day 7, the tumour weight in th e remaining liver following 30% hepatectomy was 0.321 +/- 0.058 g (mean +/- SD) which was significantly greater than that (0.245 +/- 0.040 g) in sham operations (P < 0.05). However, the tumour weight (0.156 +/- 0.067 g) in th e remaining liver following 60% hepatectomy was significantly lower than th at in sham animals (P < 0.005). The number of TdT-mediated dUTP nick-end la belling (TUNEL) positive tumour cells was significantly increased in 60% he patectomy as compared with the sham and 30% hepatectomy group. The mRNA exp ression of TGF-beta 1, TNF-alpha and Fas in the tumour portion of 60% hepat ectomy, was higher than that in 30% hepatectomy group. Plasma levels of TGF -beta 1 were inversely correlated with intrahepatic tumour weights. These r esults suggest that major hepatic resection may lead to an increased induct ion of apoptosis for the remaining hepatic tumour. (C) 2000 Cancer Research Campaign.