[8p11 myeloproliferative syndrome]

The 8p11 myeloproliferative syndrome (EMS) is named as stem cell leukemia/lymphoma syndrome, and is an aggressive neoplasm associated with chromosomal translocations involving the fibroblast growth factor receptor 1 (FGFR1) tyrosine kinase gene on chromosome 8p11-12. EMS is a syndrome characterized by peripheral blood leucocytosis with eosinophilia, myeloid hyperplasia of bone marrow, and T-cell lymphoblastic leukemia/lymphoma. Clinically, EMS is an aggressive disease with a short chronic phase before rapid transformation into acute leukemia. Its prognosis is poor. The only curative option for patients with EMS at this time appears to be bone marrow or stem cell transplantation. At the molecular level, all cases carry a chromosomal abnormality involving the FGFR1 gene at chromosome 8p11. The novel chimeric proteins foster dimerization and ligand-independent activation of FGFR1 tyrosine kinase, subsequently promoting activation of downstream pathways involved in proliferation and malignant transformation of cells. Currently, 13 translocations and 1 insertion have been identified. Here, the current review mainly focuses on molecular genetic features, pathogenic mechanisms and therapy of EMS.