Early PCR-negativity after allogeneic BMT in adults with t(4;11) ALL in the absence of acute or chronic GVHD

Acute lymphoblastic leukaemia (ALL) with the t(4;11) translocation has a ve ry poor prognosis following conventional chemotherapy. Many patients are of fered an allogeneic BMT in first remission. We report on the impact of allo geneic BMT on three patients with t(4;11) ALL in first remission. Median ag e was 20 years. One patient received marrow from an HLA-identical sibling a nd the other two from unrelated donors, All three engrafted and none of the patients developed acute or chronic GVHD, Remission status was monitored u sing a sensitive nested RT-PCR to detect the ALL-1/AF-4 hybrid transcript. All three were PCR-negative at 3 months post-BMT. One of the unrelated reci pients died of a fungal infection 4 months post-BMT. The other two are aliv e and in molecular remission at 21 and 24 months post-BMT. This is the firs t report of longitudinal follow-up of t(4;11) ALL post-allogeneic BMT by PC R. The early attainment of molecular remission in the absence of GVHD sugge sts that the conditioning regimen may have been more important than a graft -versus-leukaemia effect in these patients. Follow-up of larger numbers of patients will be required to confirm these preliminary observations.