SURVIVAL WITH BONE-MARROW TRANSPLANTATION VERSUS HYDROXYUREA OR INTERFERON FOR CHRONIC MYELOGENOUS LEUKEMIA

Hydroxyurea, interferon, and HLA-identical sibling bone marrow transpl antation are common therapies for chronic myelogenous leukemia (CML) i n chronic phase. Which is best is controversial. The purpose of this s tudy was to compare survival of patients with CML receiving HLA-identi cal sibling transplants versus hydroxyurea or interferon. The transpla nt cohort included 548 recipients of HLA-identical sibling transplants , reported to the International Bone Marrow Transplant Registry. The n ontransplant cohort included 196 patients receiving hydroxyurea (n = 1 21) or interferon (n = 75) on a randomized trial of the German CML Stu dy Group. Survivals were compared using proportional hazards regressio n with fixed and time-dependent variables to adjust for patient differ ences and changing risks over time. For the first 18 months after diag nosis, mortality was higher in the transplant than the nontransplant c ohort (relative risk [RR], 5.85; P < .0001). From 18 to 56 months, mor tality was similar (RR, 0.80; P = .38). After 56 months, mortality was lower in the transplant cohort (RR, 0.16; P < .0001). Seven-year surv ival probabilities (95% confidence interval) were 58% (50% to 66%) wit h transplant and 32% (22% to 41%) with hydroxyurea or interferon. Ther e was a significant survival advantage for hydroxyurea or interferon i n the first 4 years after diagnosis and for transplants starting 5.5 y ears after diagnosis. For transplants done within 1 year of diagnosis, the survival advantage for transplantation began earlier. Survival ad vantage for transplants was greater and occurred earlier in patients w ith intermediate-and high risk prognostic features than in those with low-risk features. This study confirms higher early mortality, but a l ong-term survival advantage for HLA-identical sibling transplants over hydroxyurea or interferon in CML. (C) 1998 by The American Society of Hematology.