Cytosine arabinoside and 6-thioguanine in the treatment of childhood acute myeloblastic leukemia.

Twenty children with acute myeloblastic leukemia were given induction and maintenance regimens combining cytosine arabinoside (ARA-C) and 6-thioguanine (TG). Two died before completing induction therapy and were considered unevaluable. Of the 18 remaining patients, 3 died shortly after induction, 2 had no response, 1 had a partial response and 12 (66%) had a complete remission (CR) lasting 4 to 68 months. Six still survive: two in their initial CR and four who relapsed but were reinduced to CR. Although no prophylactic central nervous system (CNS) therapy was given, only one patient has developed CNS involvement after diagnosis. Two girls became pregnant while on maintenance therapy. One delivered a normal, full-term infant; both she and the child are well 24 months later.