Long-term follow-up of patients with CLL treated with allogeneic hematopoietic transplantation.

We investigated the long-term outcome of allogeneic stem-cell transplantation after myeloablative conditioning regimen as treatment for patients with chronic lymphocytic leukemia. Patients were eligible for our study if they were refractory or failed a prior response to fludarabine. The conditioning regimen consisted of high-dose CY 60 mg/kg daily for 2 days and fractionated TBI. One patient received BEAM because of prior radiation. GvHD prophylaxis consisted of CYA or tacrolimus and MTX in the majority of patients. Twenty eight patients were treated. nineteen had disease that was refractory to fludarabine. The median number of prior chemotherapy regimens per patient was 3. Twenty had HLA-identical donors and one had a one-Ag mismatched sibling donor. Seven patients had a matched unrelated transplant. The median follow-up time for the surviving patients was 66 months. By univariate analysis, chemosensitivity was the only factor that predicted a better outcome. For the chemosensitive patients, the overall survival was 78%, compared with 31% for those with refractory disease (P = 0.05). Progression-free survival at 5 years was 78% for the chemosensitive and 26% for those who were refractory to conventional chemotherapy at the time of transplantation (P = 0.03). Three patients (11%) died within 100 days of transplant. The actuarial risk of acute Grade II-IV GvHD was 49%. Only one patient developed acute Grade III GvHD. Allogeneic transplantation is probably curative for a subset of patients with chronic lymphocytic leukemia. Patients should be considered for clinical trials involving allogeneic transplantation at an earlier stage prior acquiring chemorefractoriness.