Purpose: The impact of a second marrow transplant on long-term disease-free survival (DFS) was evaluated for 77 consecutive patients aged 2 to 51 years who relapsed subsequent to allogeneic marrow transplantation after high-dose chemotherapy and total-body irradiation (TBI).
Patients and methods: Patients received a second transplant for recurrent chronic myelogenous leukemia (CML) (n = 28), acute myelogenous leukemia (AML) (n = 32), and acute lymphoblastic leukemia (ALL) (n = 15) or lymphoma (n = 2) that used the same marrow donor as the initial transplant. High-dose chemotherapy of busulfan (BU) and cyclophosphamide (CY), or CY, carmustine (BCNU), and etoposide (VP-16), was used as a preparative regimen for the second transplant. Graft-versus-host disease (GVHD) prophylaxis consisted of the following: no prophylaxis (n = 8), T-cell depletion (n = 36), methotrexate (MTX) only (n = 21), cyclosporine (CSP) only (n = 1), MTX and CSP (n = 9), or anti-thymocyte globulin (ATG) and prednisone (n = 2).
Results: Engraftment occurred in the 74 assessable patients. Severe veno-occlusive disease (VOD) was the most frequent cause of grades 3 and 4 regimen-related toxicity (RRT); it occurred in 20 patients. The probability of death before day 100 from nonleukemic causes was 36%. The probability of relapse after second transplant was 70%, and the DFS rate was 14% (median DFS, 36 months; range, 22 to 87). The DFS rates for ALL, AML, and CML were 8%, 10%, and 25%, respectively. Multivariate analysis showed that the risk of relapse was inversely associated with acute GVHD (relative risk [RR] of relapse = 0.2; P = .0009). No other factor was associated with relapse. DFS was associated with the presence of acute GVHD (RR of treatment failure = 0.5; P = .0085), and a reduction of DFS was associated with severe VOD (RR = 10.6; P = .0001) and those patients older than 10 years (RR = 2.5; P = .0337).
Conclusion: These data show that some patients may benefit from a second marrow transplant for recurrent leukemia after an initial marrow transplant. Younger patients and patients with CML especially should be considered as potential candidates for a second transplant.