Comparison of nephrectomy and/or doxorubicin treatment in rabbit renal VX-2 carcinoma.

To compare survival after local intra-arterial and intravenous administration of doxorubicin, VX-2 carcinoma was implanted in one kidney of 48 rabbits. Treatments were given 9-14 days after tumor implantation. Survival after doxorubicin was significantly longer than the controls, whereas no difference was established between intra-arterial or intravenous treatment. Overall only 9 of 32 doxorubicin-treated rabbits were cured at autopsy after 18 months. It was assumed that circulating tumor cells from tumor implantation resulted in "primary" lung metastases. To kill circulating tumor cells intravenous doxorubicin was given immediately before implantation in 40 rabbits, followed by combinations of nephrectomy and doxorubicin. Doxorubicin without nephrectomy cured 8 of 16 rabbits, whereas doxorubicin combined with nephrectomy cured 4 of 16. Doxorubicin improved survival in responders, but likelihood of response was limited. Nephrectomy did not improve survival, most likely due to metastatic seeding at implantation. Intravenous doxorubicin immediately before did not prevent metastatic spread in connection with tumor implantation.