Pros and cons of splenectomy in patients with myelofibrosis undergoing stem cell transplantation

During fetal development, the spleen is a major hemopoietic organ. In the a dult human, this task is relinquished to the bone marrow. However, under th e stress of certain pathologic conditions, extramedullary hemopoiesis may a gain occur in the spleen. This is especially true for diseases of the marro w, in particular, myeloproliferative disorders such as agnogenic myeloid me taplasia, which is associated with severe fibrosis of the marrow space. At the same time, the spleen sequesters blood cells and contributes to periphe ral blood cytopenias, which may improve following splenectomy. However, suc cess is unpredictable, and the operative mortality of splenectomy is on the order of 10%, As a growing number of patients undergo hemopoietic stem cel l transplantation as definitive therapy for myelofibrosis, the decision on splenectomy has additional ramifications since the spleen plays an importan t role in the kinetics of engraftment of donor cells and in immune reconsti tution. We conclude from our analysis of available information that the ben efit of splenectomy is difficult to predict, although after transplantation splenectomized patients have faster hemopoietic recovery, It appears that the most important indication for splenectomy in these patients is the reli ef of symptoms from massive spleen enlargement.