How should acute lymphoblastic leukaemia relapsing after bone-marrow transplantation be treated?

21 of 63 patients given bone-marrow transplantation (BMT) for acute lymphoblastic leukaemia (ALL) relapsed between day 75 and day 1126 after BMT. 19 patients were given leukaemic induction treatment with standard combination chemotherapy. 7 patients achieved a sustained remission, of whom 5 are alive in remission 88-1240 days after relapse; the 2 others died during a second BMT. 2 of the remaining 14 obtained partial remission but all 14 ultimately died with relapsed leukaemia. A favourable outcome for ALL relapsing after BMT was predicted by the pace of the disease: the 5 survivors had an interval between diagnosis and first relapse of more than 2 years and a disease-free period after BMT of 500 days or more. These results indicate that further conventional chemotherapy should be used rather than a second marrow transplant to prolong disease-free survival in patients with ALL relapsing after BMT.