Blood, 15 December 2002, Vol. 100, No. 13, pp. 4668-4670
BRIEF REPORT
Late complications following treatment for severe aplastic anemia
(SAA) with high-dose cyclophosphamide (Cy): follow-up of a
randomized trial
John F. Tisdale,
Jaroslaw P. Maciejewski,
Olga Nuñez,
Stephen J. Rosenfeld, and
Neal S. Young
From the Hematology Branch, National Heart, Lung, and
Blood Institute, National Institutes of Health, Bethesda, MD.
High-dose cyclophosphamide (Cy) has been promoted as curative
therapy for severe aplastic anemia (SAA). However, our randomized trial
comparing antithymocyte globulin (ATG) and Cy was terminated early
because of excess morbidity/early mortality in the Cy arm. We now
report analysis of secondary endpoints at a median of 38 months.
Relapse occurred in 6 (46%) of 13 responders in the ATG arm versus 2 (25%) of 8 in the Cy arm (P = .38). Five (31%) of 16 patients in the ATG arm and 4 (27%) of 15 patients in the Cy arm had
evidence of paroxysmal nocturnal hemoglobinuria (PNH) at
diagnosis, with no substantial change in the overall percentage of glycophosphatidyl inositol (GPI)-anchored protein-deficient neutrophils over extended follow-up in individual patients in either
arm. Bone marrow cytogenetic abnormalities have been observed among
surviving patients in both arms (2 of 14 ATG versus 1 of 12 Cy,
P = .70). High-dose Cy does not prevent relapse or clonal evolution in SAA.
