Chemotherapy for murine ovarian cancer: a rationale for ip therapy with adriamycin

The metastatic spread of a trnasplantable murine ovarian cancer is similar to the spread of ovarian cancer in patients with advanced disease, making it a useful model to investigate novel experimental therapies. The ip inoculation of 10(6) tumor cells into C3HeB/FeJ mice leads to the formation of ascites, sub-diaphragmatic tumor deposits, intra-abdominal tumors, and death within 25 days. Adriamycin (ADR) was found to be an active agent against this murine ovarian cancer. The effects of ADR were dependent upon the route of administration. A single ip LD10 dose of ADR (5 mg/kg) administered 2 days after inoculation with 10(6) tumor cells produced long-term survival (greater than 60 days) in 70% of the mice. An iv LD10 dose had no effect on survival. The survival advantage of ip ADR (compared to the iv route) was found to be related to: (a) a greater suppression of DNA synthesis in the tumor; (b) a rapid penetration of ADR into the nuclei of ascites tumor cells and into sub-diaphragmatic tumor deposits; and (c) significantly higher levels of ADR in tumor cells following ip administration. The ip route may also be less cardiotoxic since the peak levels after an iv dose were three times greater than after an equal ip dose. If local toxicity does not prove to be a major problem, then ip ADR may be a useful mode of therapy in patients with intra-abdominal tumors.