Effects of doxorubicin on cancer cells after two-thirds hepatectomy in rats.

A rat model of liver metastases generated by intraportal injection of syngeneic tumor cells after two-thirds hepatectomy was used to determine the optimal regional chemotherapeutic modality for early hepatic metastases. WKA rats had viable tumor cells injected directly into the portal vein after two-thirds hepatectomy. Ten rats were used as a control; the remaining groups were given doxorubicin (4/3 mg/kg) injected directly into the hepatic artery at 24 hr, 72 hr, and 7 days (after liver regeneration) postoperatively. The mean survival period in each group was 21.0, 20.0, 20.5, and 20.7 days, respectively, compared with those treated with doxorubicin (4 mg/kg) injection at 24 hr, 72 hr, and 7 days postoperatively, with a mean survival period in each group of 20.0, 21.6, and 25.6 days, respectively. When a comparison was made with regard to the doses of doxorubicin administered, statistically significant differences in survival rates were recognized between the rats that had doxorubicin (4 mg/kg) injection 7 days postoperatively and the others (P < 0.01). Based on these findings, we believe that appropriate adjuvant chemotherapy should be given after the liver regeneration phase.