Donor Availability and Clinical Trials for Allogeneic Stem Cell Transplantation—Reply
- John Koreth, MBBS, DPhil john_koreth@dfci.harvard.edu;
- Corey S. Cutler, MD, MPH, FRCPCDepartment of Hematologic MalignanciesDana-Farber Cancer InstituteBoston, Massachusetts
Since this article does not have an abstract, we have provided the first 150 words of the full text.
- KEYWORDS:
- HLA ANTIGENS
- LEUKEMIA, MYELOID, ACUTE
- STEM CELL TRANSPLANTATION
- SURVIVAL
- TISSUE DONORS
- TRANSPLANTATION, HOMOLOGOUS
In Reply: As noted by Dr Büchner, prospective biologic assignment trials based on donor availability are not randomized comparisons. Analyzed on a donor vs no-donor basis, they have nevertheless been widely accepted as providing good-quality evidence of treatment effect, as no evidence of major bias has been identified.
Büchner identifies potential bias in the inclusion of both “no-sibling” and “no HLA-matched sibling” patients in the no-donor group. One scenario is that no-sibling patients would be immediately assigned to the no-donor group, while patients with siblings may have indeterminate status and be excluded from the analysis if they experienced an early event (eg, death) before the completion of all HLA typing. The differential exclusion of early events in patients who may indeed have had an HLA-matched sibling donor represents a potential bias. An alternative scenario is that patients with siblings who were untyped at the time of an early event may …
