Treatment of acute lymphoblastic leukaemia in adults.

Between 1972 and 1982, 112 consecutive previously untreated adults (aged 15-69 years, median 26) commenced therapy for acute lymphoblastic leukaemia (ALL) at St Bartholomew's Hospital. The first 63 patients entered into the study received initial treatment which comprised four cycles of adriamycin and vincristine, prednisolone and L-asparaginase with the first cycle (OPAL). In 1978, six cycles were given, with escalating doses of adriamycin and cyclophosphamide from cycle 3 (HEAV'D). Central nervous system (CNS) prophylaxis incorporated intrathecal methotrexate and cytosine arabinoside with cranial irradiation. Maintenance chemotherapy consisted of 6-mercaptopurine, cyclophosphamide and methotrexate for 3 years. Results obtained with the OPAL and HEAV'D regimens were not significantly different. The overall complete remission (CR) rate was 66% (73/111), factors correlating unfavourably with achievement of CR being advanced age (P less than 0.001) and L3 morphology/B-ALL immunophenotype (P less than 0.01). Fifty-three patients have relapsed, the bone marrow being the primary site in 43. Extramedullary relapse alone occurred in 10 (seven CNS, two testicular and one skin). Only three of the 64 patients who had complete CNS prophylaxis subsequently relapsed in the CNS as an isolated site. One patient died in CR, 19 remain in continuous CR between 2.5 and 10.5 years. The median duration of remission of the 73 patients who achieved CR was 18.5 months, factors correlating favourably with duration of CR being low blast cell count at presentation (P less than 0.002) and common ALL immunophenotype (P less than 0.04). Twenty-four patients remain alive, with a median survival of all patients of 18 months. Long-term survival is possible for approximately 20% of adults with ALL treated relatively intensively.