Prediction and prevention of relapse of acute lymphoblastic leukaemia after bone marrow transplantation

Results of bone marrow transplantation (BMT) in 63 adults and children with ALL transplanted in the 5-year period 1979-83 were analysed. Twenty-one patients (33%) relapsed, 25% of the group died in relapse and 19% died from complications of BMT. The actuarial disease-free survival at 6 years was 38%. Relapse after BMT could be predicted by standard prognostic diagnostic features such as age, sex, cell type and presenting blast cell count. Patients transplanted in first remission selected for their poor prognosis had a lower relapse risk than a similar group of poor prognosis patients transplanted in second or subsequent remission (P less than 0.05). Relapse following second and subsequent remission BMT was predicted by a score based on standard prognostic features or by the pace of the disease: patients with an interval of less than 2 years between diagnosis and first relapse having a 15% actuarial disease-free survival, compared with 81% for patients with an interval greater than 2 years (P less than 0.001). These results emphasize that ALL is a heterogeneous disease and establishes the importance of determining relapse risk when selecting BMT and other treatment schedules for ALL patients.