Relevance of marrow fibrosis in bone marrow transplantation: a retrospective analysis of engraftment

A retrospective study compared posttransplant engraftment parameters in 203 patients with myelofibrosis (MF) with those in a population of 203 matched controls without MF. There were no significant differences between these groups in the proportions of patients who died without achieving engraftment and in the disease-free survival distributions. Furthermore, comparisons between the two groups of patients reaching the respective endpoints showed no differences in the time distributions for reaching 0.5 or 1.0 x 10(9)/L granulocytes, but the time to platelet transfusion independence was 3 days longer in patients with MF. In further analysis, results for 33 patients with severe MF were compared with those of their respective controls. The proportions of patients with severe MF who died without reaching these engraftment endpoints and the disease-free survival distributions in the two groups were similar. Among patients who reached the respective engraftment endpoints, there was no statistically significant difference in the pace of granulocyte recovery. In patients with severe MF, there was a 7- day delay in the time to reach platelet transfusion independence and a 2-day delay in the time to reach red blood cell independence, but the differences were not statistically significant. The present results do not substantiate concerns raised by earlier studies. MF may delay the time to reach platelet independence by approximately 3 days and may increase platelet transfusion requirements, but no other perturbation of hematopoietic reconstitution was apparent.