Sensitivity to six antitumor drugs differs between primary and metastatic liver cancers

Chemosensitivity to six different types of antitumor drugs was assayed using the succinate dehydrogenase inhibition (SDI) test, with regard to effects of 29 tissues from primary hepatocellular carcinomas (PHC) and 12 metastatic liver cancers. Succinate dehydrogenase activity in the PHC was significantly decreased by adriamycin (ADM), mitomycin C (MMC), aclacinomycin A (ACR) (P < 0.01), and 5-fluorouracil (5-FU), cisplatin (DDP) and carboquone (CQ) (P < 0.05), as compared to findings in tissues from the metastatic liver tumors. In PHC, chemosensitivity to antitumor drugs in the SDI test was positive in 58.6% of tissues exposed to ADM, 60.7% with MMC, 11.1% with 5-FU, 65.4% with DDP, 65.5% with ACR and 64.3% with CQ. On the contrary, the positive rates seen in metastatic liver tissues were 18.2% in DDP and 8.3% in CQ, and there was no positive chemosensitivity in tissues exposed to ADM, MMC, 5-FU and ACR. Therefore, PHC will show a better response than metastatic liver cancers to antitumor drugs. Our observations show that the selection of sensitive drugs is most important to improve the response rate and the survival time of patients. The SDI test proves useful for planning clinical management.