[A study on the correlation between the concentration of antitumor agent and the clinical effect. An experience with THP-ADM].

A new anthracycline antibiotic agent, THP-adriamycin (THP-ADM) was administered to patients with malignant head and neck tumors. Among them, intraarterially injected cases achieved excellent primary effects; 3 CR, 4 PR and 2 NC out of 9 cases. Patients received THP-ADM 10 mg/body every other day, to a total of 100 mg. In order to elucidate the factors responsible for this result, the concentration level of THP-ADM in plasma, blood cells and in tumor tissue was measured by high-performance liquid chromatography at various time intervals. Changes in concentration of THP-ADM were similar in both intraarterial and intravenous cases. Among these, the concentration levels in blood cells were always higher than in the plasma and were reduced rapidly with the passage of time; about hour 1 after administration, THP-ADM levels diminished considerably, especially in the plasma. On the other hand, in tumor tissue, the concentration level was exceedingly high at 1 hour after injection, and was still high-24 hours later. In intraarterial cases, these levels were about seventy times higher than in intravenous cases at 1 hour after injection. From these observations, the authors found a very good correlation between the tissue concentration level and the clinical effects obtained.