Second hematopoietic SCT in patients with thalassemia recurrence following rejection of the first graft.

There is a substantial incidence of graft failure in patients with thalassemia after myeloablative conditioning regimens especially in class 3 patients in whom its incidence could be as high as 8-38.5%. Most patients with graft failure have recurrence of thalassemic marrow. Historically, results of second transplants for thalassemia were poor because of a high rejection rate and/or increased TRM. Sixteen patients with thalassemia recurrence following rejection of the first graft and with a median age of 9 years (range, 4-20) were given second transplants using BM (n=7) or PBSC (n=9) after preparation with a new treatment protocol. All but two patients received stem cells from the same donor. The median interval between two transplants was 28 months (range, 8-204). The sustained engraftment rate was high (94%) with only one patient having primary graft failure. The probability of overall survival, event-free survival, TRM and graft failure were 79, 79, 16 and 6%, respectively. There were three transplant-related deaths. Thirteen patients are alive with Lansky/Karnofsky score of 100. This intensified treatment protocol was well tolerated with no significant increase in toxicity. The excellent results obtained with this new preparative regimen allow us to recommend it for second transplantation for patients with thalassemia recurrence.