Precursor T-Lymphoblastic Lymphoma Associated with t(8;9)(p11.2;q33): A Case Report and Review of the Literature.

The 8p11 myeloproliferative syndrome (EMS) is an aggressive neoplasm associated with chromosomal translocations involving the fibroblast growth factor receptor 1 (FGFR1) tyrosine kinase gene on chromosome 8p11-12. A new case of a 9-year-old boy with leukocytosis, eosinophilia, and general lymphadenopathy is reported in this study. Bone marrow examination showed eosinophilic hyperplasia, with blast cells amounting to 6-7%. Karyotyping revealed cytogenetic abnormalities, including t(8;9)(p11.2;q3?3). Fluorescence in situ hybridization for the FGFR1 gene rearrangement yielded positive results. Lymph node biopsy confirmed the diagnosis of precursor T-lymphoblastic lymphoma. The patient responded to chemotherapy, and unmatched related bone marrow transplantation was performed. A successful outcome was obtained with complete cytogenetic remission maintained for 14 months to date. In the future, FGFR1 inhibitors might be specific and effective therapeutic targets for EMS. Similar cases from the literature are reviewed.