Objective: The aim of this study was to evaluate whether partial hepatectomy (PH) enhances the growth of implanted intrahepatic and subcutaneous tumor and whether octreotide (OCT) can alter tumor growth.
Methods: Ninety-one ACI rats (125 g) underwent a laparotomy; 51 had a 66% PH and 40 were controls. Morris hepatoma 3924A was implanted in the liver (IH) of 29 PH and 26 controls and subcutaneously (SC) in 22 PH and 14 control rats. OCT, 50 mg/kg, was administered intraperitoneally twice a day to 23 PH rats with IH (n = 15) or SC (n = 8) tumor implants. The remaining PH rats received a similar volume of saline (NS). PH and control animals were evaluated for tumor volume, metastases, and tumor and liver weight at 7 and 15 days.
Results: Group I (PH + IH + NS) showed a sixfold increase in IH tumor volume and 100% increase in metastases versus group II (controls + IH + NS) at 15 days postimplant (P < .01). Group III (PH + SC + NS) had a fourfold increase in SC tumor volume at 7 and 15 days versus group IV (control + SC + NS, P < .02). Group V (PH + IH + OCT) showed a tenfold reduction of IH tumor volume (P < .01) and 20% decrease in liver weight (P < .03) when compared with group I at 15 days. Group VI (PH + SC + OCT) similarly showed a threefold reduction of SC tumor volume (P < .01) and 20% decrease in tumor weight (P < .05) versus group III.
Conclusion: Growth of IH and SC hepatoma is enhanced after PH and inhibited by OCT. This suggests that factors influencing hepatic replication also affect local and remote tumor growth. OCT action may be related to the presence of somatostatin receptors or caused by a direct antiproliferative effect.