DECREASED REJECTION AND IMPROVED SURVIVAL OF FIRST AND 2ND MARROW TRANSPLANTS FOR SEVERE APLASTIC-ANEMIA (A 26-YEAR RETROSPECTIVE ANALYSIS)

Between 1970 and 1996, 333 patients with severe aplastic anemia underw ent HLA-matched related marrow transplant after conditioning with cycl ophosphamide (CY), Thirty-five percent of patients transplanted betwee n 1970 and 1976 (group 1), 12% of those transplanted between 1977 and 1981 (group 2), and 9% of patients transplanted between 1982 and 1997 (group 3) had graft rejection. Graft rejection occurred later among gr oup 3 patients (median, 180 days) than among those in groups 1 and 2 ( medians, 28 and 47 days, respectively; P < .001 group 3 v 2). In group 3, 92% of rejecting patients underwent a second transplant, compared with 78% and 77% in groups 1 and 2, respectively. Group 1 patients rec eived Various conditioning regimens before second transplant, whereas most patients of groups 2 and 3 received CY combined with antithymocyt e globulin (ATG). Graft-versus-host disease (GVHD) prophylaxis after s econd transplant consisted of methotrexate (MTX) for all group 1 and 2 patients, whereas group 3 patients received MTX combined with cyclosp orine (CSP). Over the three time periods studied, first graft rejectio n decreased from 35% to 9%, and the proportion of rejecting patients u ndergoing second transplants increased from 77% to 92%. The 10-year pr obability of survival after second transplants increased from 5% to 83 %. Multivariate analysis showed MTX/CSP GVHD prophylaxis to be a signi ficant factor accounting for the increase in patient survival after se cond transplant. (C) 1998 by The American Society of Hematology.