title: JAK2 V617F positive essential thrombocythemia developing in a patient with CD5⁻ chronic lymphocytic leukemia.
abstract: Coexistence of chronic lymphocytic leukemia (CLL) and essential thrombocythemia (ET) in a patient is extremely rare, with only 10 cases reported thus far in literature. This paper describes a 94-year-old male having atypical B-CLL with CD5⁻ (CD5⁻) phenotype and ET. In this patient, we performed interphase fluorescence in situ hybridization (FISH) analysis which revealed 13q14.3 deletion in 31% of B-lymphocyte nuclei and RB1 deletion in 27% of B-lymphocyte nuclei, but not in neutrophils and T-lymphocytes. Furthermore, we identified JAK2 V617F mutation in the peripheral blood nucleated cells and neutrophils, but not in the B- and T-lymphocyte populations. Therefore, it was concluded that the occurrence of CD5− B-CLL and ET in this patient was pathogenically independent.
authors.affiliation: Department of Hematology, Shanghai First People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200080, China. weiju@medmail.com.cn
authors.forename: Ju
authors.initials: J
authors.lastname: Wei
authors.forename: Chun
authors.initials: C
authors.lastname: Wang
authors.forename: You-Wen
authors.initials: YW
authors.lastname: Qin
authors.forename: Jun
authors.initials: J
authors.lastname: Zhu
authors.forename: Yang-Rong
authors.initials: YR
authors.lastname: Gao
authors.forename: Qi
authors.initials: Q
authors.lastname: Cai
authors.forename: Shi-Ke
authors.initials: SK
authors.lastname: Yan
mesh_terms: D000369:Aged, 80 and over; D018956:CD5 Antigens / Q000378:metabolism*; D006801:Humans; D017403:In Situ Hybridization; D053614:Janus Kinase 2 / Q000235:genetics*; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000235:genetics* / Q000378:metabolism; D008297:Male; D009154:Mutation; D013920:Thrombocythemia, Essential / Q000235:genetics* / Q000378:metabolism
chemical_list: D018956:CD5 Antigens; D053614:Janus Kinase 2