Treatment of adult acute lymphoblastic leukaemia

Eighty-five consecutive patients with acute lymphoblastic leukaemia (ALL), having a median age of 24 years (range 10-69 years), underwent induction and consolidation chemotherapy with weekly parenteral vincristine, Adriamycin, l-asparaginase and daily oral prednisone (VAAP), followed by standard (CNS) prophylaxis. Maintenance therapy was given for 3 years and consisted of daily 6-mercaptopurine, weekly methotrexate and monthly intrathecal therapy, with drug intensification comprising either vincristine, Adriamycin and l-asparaginase (VAA) or cyclophosphamide, vincristine, cytosine arabinoside and prednisone (COAP). Complete remission (CR) was obtained in 59 patients (69%) and only the French-American-British (FAB) L1 morphology was a significant predictive factor (P = 0.048). Twenty-three patients failed to achieve CR and of these 12 had primary drug resistance. Median follow-up is currently 260 weeks, median predicted survival of all patients is 58 weeks and for those who achieved CR it is 104 weeks. Median duration of CR is 70 weeks. Of the prognostic factors for survival, only FAB L1 subtype was significant. Bone marrow relapses occurred in 29 patients, and of these 9 (31%) achieved CR. There has been CNS relapse in two patients and both have died. Eleven patients continue in CR off therapy, with a median of 152 weeks. This regimen is effective, with acceptable toxicity, and a number of patients are potentially cured. The incidence of resistant and relapsing disease is an argument for further intensifying both induction and postinduction therapy.