Second hematopoietic SCT for leukemia relapsing after myeloablative T cell-depleted transplants does not prolong survival

Patients with leukemia relapsing after allogeneic hematopoietic SCT have a dismal prognosis. A second SCT offers a further opportunity for cure, but has a high rate of treatment failure. To determine the utility of this option, we analyzed 59 consecutive patients relapsing after a myeloablative HLA-matched sibling T cell-depleted (TCD) SCT. Twenty-five patients (13 relapsing within 6 months and 12 relapsing between 6 and 170 months after the first SCT) received a T-replete second SCT. Thirty-eight patients relapsing early had a shorter survival than the 21 patients relapsing later (median 96 vs 298 days, P =0.0002). In patients relapsing early, the second SCT did not improve OS compared with patients receiving non-SCT treatments (median survival 109 vs 80 days, P =0.41). In patients relapsing late, despite an early trend in favor of second SCT, survival was comparable for patients receiving a second SCT compared with non retransplanted patients (median survival 363.5 vs 162 days, P =0.49). Disappointingly, our results do not demonstrate an important survival benefit for a second T-replete allogeneic SCT to treat relapse following a TCD SCT.