title: Flow cytometry immunophenotypic analysis of Philadelphia-negative myeloproliferative neoplasms: Correlation with histopathologic features.
abstract: BACKGROUND
  Compared with the proven utility of flow cytometry immunophenotyping (FCI) analysis in the workup of myelodysplastic syndromes (MDS), immunophenotypic alterations in myeloproliferative neoplasms (MPN) have been less studied and the potential utility of FCI is not defined.
  
  
  METHODS
  Bone marrow (BM) samples of 83 Philadelphia-negative MPN patients were assessed by multicolor FCI including 27 with essential thrombocythemia (ET); 17 polycythemia vera (PV); 33 primary myelofibrosis (PMF) and 6 MPN-unclassifiable (MPN-U). The time interval from initial diagnosis of MPN to FCI analysis was 18 months (0-370). Ninety-five age-matched MDS patients with a similar BM blast count were included for comparison.
  
  
  RESULTS
  Immunophenotypic alterations, either in CD34(+) cells or myelomonocytic cells, were detected in 82 of 83 (99%) MPN cases. FCI abnormalities were more frequently observed in cases with substantial myelofibrosis but not different between PMF and fibrotic stage of ET/PV. Furthermore, FCI abnormalities were more frequent in cases with ≥5% BM blasts and/or circulating blasts (P = 0.006); as well as cases with an abnormal karyotype (P = 0.036); but not associated with morphologic dysplasia or JAK2 mutation status. Comparing with MDS, FCI abnormalities were overall less pronounced in MPN cases (P = 0.001).
  
  
  CONCLUSIONS
  MPNs exhibit frequent immunophenotypic alterations, more pronounced in cases with adverse histopathologic features. These findings illustrate that immunophenotypic alterations are a part of constellational findings in MPN, and correlate progressively with disease stage. The study results also suggest a role of FCI in diagnosis of MPN and monitoring disease over time and after therapy.
authors.affiliation: Department of Hematopathology, the University of Texas MD Anderson Cancer Center, Houston, Texas.|Department of Laboratory Medicine, the First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, Guangdong, China.
authors.forename: Juan
authors.initials: J
authors.lastname: Ouyang
authors.affiliation: Department of Hematopathology, the University of Texas MD Anderson Cancer Center, Houston, Texas.|Department of Hematology Oncology, the Second Affiliated Hospital of Xiangya Medical School Central South University, Changsha, Hunan, China.
authors.forename: Wenli
authors.initials: W
authors.lastname: Zheng
authors.affiliation: Department of Hematopathology, the University of Texas MD Anderson Cancer Center, Houston, Texas.
authors.forename: Qi
authors.initials: Q
authors.lastname: Shen
authors.affiliation: Department of Hematopathology, the University of Texas MD Anderson Cancer Center, Houston, Texas.
authors.forename: Maitrayee
authors.initials: M
authors.lastname: Goswami
authors.affiliation: Department of Hematopathology, the University of Texas MD Anderson Cancer Center, Houston, Texas.
authors.forename: Jeffrey L
authors.initials: JL
authors.lastname: Jorgensen
authors.affiliation: Department of Hematopathology, the University of Texas MD Anderson Cancer Center, Houston, Texas.
authors.forename: L Jeffrey
authors.initials: LJ
authors.lastname: Medeiros
authors.affiliation: Department of Hematopathology, the University of Texas MD Anderson Cancer Center, Houston, Texas.
authors.forename: S A
authors.initials: SA
authors.lastname: Wang
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018952:Antigens, CD34 / Q000032:analysis; D001853:Bone Marrow / Q000502:physiology; D001854:Bone Marrow Cells / Q000166:cytology; D005260:Female; D005434:Flow Cytometry / Q000379:methods*; D006801:Humans; D016130:Immunophenotyping; D053614:Janus Kinase 2 / Q000235:genetics; D008297:Male; D008875:Middle Aged; D010677:Philadelphia Chromosome; D011087:Polycythemia Vera / Q000175:diagnosis* / Q000235:genetics; D055728:Primary Myelofibrosis / Q000175:diagnosis* / Q000235:genetics; D013920:Thrombocythemia, Essential / Q000175:diagnosis* / Q000235:genetics; D055815:Young Adult
chemical_list: D018952:Antigens, CD34; C507924:JAK2 protein, human; D053614:Janus Kinase 2
keywords: Philadelphia-negative myeloproliferative neoplasm; blasts; cytogenetic; dysplasia; flow cytometry; myelofibrosis