非定型的白血病の病態並びに治療に関する研究　第2編　非定型的白血病の治療に関する検討：(4)N-behenoyl-1-β-D-arabinofuranosyl-cytosine(BHAC) 少量療法の臨床効果

Therapeutic effects of low-dose (4)N-Behenoyl-β-D-Arabinofuranosylcytosine(BHAC) on 52 patients with hypoplastic leukemia were analyzed to establish the optimal clinical management of hypoplastic leukemia. Among 8 patients treated with a low-dose (4)N-Behenoyl-β-D-Arabinofuranosyl cytosine (LD-BHAC) regimen, in which 50mg BHAC was administered daily intravenously by one-hour drip infusion for 14 days, 4 patients obtained complete remission (CR) and 2 patients obtained partial remission (PR). The response rate (CR+PR) was 75%. The responders were all over 65 years old. Although hematological toxicities and adverse effects on the digestive system such as anorexia and nausea were observed, they were all controllable by conventional treatments. The serum concentrations of ara-C were measured in 4 patients. Serum ara-C reached the peak concentration, 3.62-18.9 ng/ml (mean : 11.74 ng/ml), at the cessation of BHAC infusion, and a serum ara-C level of 2.75-4.89 ng/ml (mean : 3.54 ng/ml) was still present 6 hours after the cessation of infusion. Among 44 patients hospitalized before 1984, 27 patients were treated with blood transfusion and /or single antileukemic agent and 17 patients received combination chemotherapeutic regimens. Only 8 of 44 patients attained CR. The responders were all below 65 years old, and except for one patient, received combination chemotherapy. These results suggest that LD-BHAC therapy is useful in the clinical management of hypoplastic leukemia as a remission induction chemotherapy.