Protective Conditioning for Acute Graft-versus-Host Disease
http://www.100md.com
《新英格兰医药杂志》
To the Editor: Lowsky et al. (Sept. 29 issue)1 report a conditioning regimen associated with an impressively low incidence of graft-versus-host disease (GVHD). However, the dynamics of engraftment are unclear. The authors mention that "donor T cells subsequently declined in number and were markedly reduced or undetectable within 75 to 200 days after transplantation in 6 of the 37 patients." This finding suggests that late graft failure occurred in a substantial proportion of patients and consequently could in part explain the low incidence of GVHD.
In addition, in the setting of nonmyeloablative transplantation, the time to the onset of acute GVHD is significantly delayed,2 so the 100-day limit used by Lowsky et al. may not reflect the true incidence of acute GVHD.
Ernesto Ayala, M.D.
Mohamed Kharfan-Dabaja, M.D.
H. Lee Moffitt Cancer Center
Tampa, FL 33612
ayalae@moffitt.usf.edu
References
Lowsky R, Takahashi T, Liu YP, et al. Protective conditioning for acute graft-versus-host disease. N Engl J Med 2005;353:1321-1331.
Diaconescu R, Flowers C, Storer B, et al. Morbidity and mortality with nonmyeloablative compared with myeloablative conditioning before hematopoietic cell transplantation from HLA-matched related donors. Blood 2004;104:1550-1558.
The authors reply: Drs. Ayala and Kharfan-Dabaja question the low incidence of acute GVHD and the apparently high rate of late graft loss reported in our study. The diagnosis and grading of acute and chronic GVHD in our study were performed according to established consensus criteria.1,2 With a period of observation now ranging from 492 to 1339 days after transplantation, only 1 of the 37 patients (<3 percent) died from complications related to either acute or chronic GVHD — a number we consider to be impressively low, especially given the fact that almost 40 percent of the patients received grafts from unrelated donors.
Six patients in our study had graft loss within 75 to 200 days after transplantation. However, in four of these patients, the graft loss was associated with tumor progression or relapse of disease in the bone marrow. Thus, only 2 of the 37 patients (5 percent) had non–relapse-related graft loss — a fraction that is consistent with other nonmyeloablative host-conditioning regimens.
Robert Lowsky, M.D.
Robert S. Negrin, M.D.
Samuel Strober, M.D.
Stanford University Medical Center
Stanford, CA 94305
rlowsky@stanford.edu
References
Sullivan KM, Agura E, Anasetti C, et al. Chronic graft-versus-host disease and other late complications of bone marrow transplantation. Semin Hematol 1991;28:250-259.
Przepiorka D, Weisdorf D, Martin P, et al. 1994 Consensus conference on acute GVHD grading. Bone Marrow Transplant 1995;15:825-828.
In addition, in the setting of nonmyeloablative transplantation, the time to the onset of acute GVHD is significantly delayed,2 so the 100-day limit used by Lowsky et al. may not reflect the true incidence of acute GVHD.
Ernesto Ayala, M.D.
Mohamed Kharfan-Dabaja, M.D.
H. Lee Moffitt Cancer Center
Tampa, FL 33612
ayalae@moffitt.usf.edu
References
Lowsky R, Takahashi T, Liu YP, et al. Protective conditioning for acute graft-versus-host disease. N Engl J Med 2005;353:1321-1331.
Diaconescu R, Flowers C, Storer B, et al. Morbidity and mortality with nonmyeloablative compared with myeloablative conditioning before hematopoietic cell transplantation from HLA-matched related donors. Blood 2004;104:1550-1558.
The authors reply: Drs. Ayala and Kharfan-Dabaja question the low incidence of acute GVHD and the apparently high rate of late graft loss reported in our study. The diagnosis and grading of acute and chronic GVHD in our study were performed according to established consensus criteria.1,2 With a period of observation now ranging from 492 to 1339 days after transplantation, only 1 of the 37 patients (<3 percent) died from complications related to either acute or chronic GVHD — a number we consider to be impressively low, especially given the fact that almost 40 percent of the patients received grafts from unrelated donors.
Six patients in our study had graft loss within 75 to 200 days after transplantation. However, in four of these patients, the graft loss was associated with tumor progression or relapse of disease in the bone marrow. Thus, only 2 of the 37 patients (5 percent) had non–relapse-related graft loss — a fraction that is consistent with other nonmyeloablative host-conditioning regimens.
Robert Lowsky, M.D.
Robert S. Negrin, M.D.
Samuel Strober, M.D.
Stanford University Medical Center
Stanford, CA 94305
rlowsky@stanford.edu
References
Sullivan KM, Agura E, Anasetti C, et al. Chronic graft-versus-host disease and other late complications of bone marrow transplantation. Semin Hematol 1991;28:250-259.
Przepiorka D, Weisdorf D, Martin P, et al. 1994 Consensus conference on acute GVHD grading. Bone Marrow Transplant 1995;15:825-828.