Patients with acute leukemia relapsing after allotransplant and who respond to anti-leukaemia interventions are at high-risk of a second relapse. Previous studies from investigators reported an association between a positive minimal residual disease (MRD)-test after transplant and an increased risk of subsequent relapse. Also, patients developing chronic graft-versus-host disease (GvHD) after receiving DLI (donor lymphocyte infusion)for leukemia relapse after a first allotransplant have a lower likelihood of a second relapse compared with similar patients not developing chronic GvHD. And, our previous study also reported patients with chronic GvHD after DLI was associated with a greater frequency of a negative MRD-test and lower likelihood of subsequent relapse compared with similar persons not developing chronic GvHD. Based on these data the investigators designed a randomized control study to determine whether giving additional consolidation chemotherapy and DLI might decrease likelihood of second relapse in persons without chronic GvHD or with a positive MRD-test after initial post-relapse therapy with induction chemotherapy and DLI.

Inclusion Criteria:

• (1) acute leukemia in first complete or second complete remission;
• (2) relapse after an allotransplant;
• (3) had full or partial donor chimerism;
• (4) received re-induction chemotherapy and DLI and achieved a negative MRD-test.

Exclusion Criteria:

• (1) active GvHD
• (2) active infection
• (3) organ dysfunction