Allogeneic hematopoietic stem cell transplantation for myelofibrosis and chronic myelomonocytic leukemia.

The efficacy of hematopoietic stem cell transplantation (HSCT) is not well established in Philadelphia chromosome negative myeloproliferative neoplasms (Ph- MPNs). Without randomized prospective trials comparing HSCT to non-HSCT options or comparing HSCT regimens, physicians must rely on prognostic scoring systems and clinical experience when making decisions about who and when to transplant patients with Ph- MPNs. These patients are vulnerable to hepatic toxicity and graft failure after HSCT because of their increased likelihood of portal hypertension, massive splenomegaly, and extensive bone marrow fibrosis related to their disease. In this review, we aim to outline the indications and modalities of HSCT as they pertain to the Ph- MPNs and CMML based on the currently available evidence. We will further highlight the challenges of HSCT in these diseases, including but not limited to the incorporation of JAK inhibitors into HSCT for myelofibrosis.