title: Clinical presentation, progression, and outcome of patients with clonal B-cell counts of less than 5 × 10(9)/l, 5 to 10 × 10(9)/l, and more than 10 × 10(9)/l and chronic lymphocytic leukemia immunophenotype.
abstract: OBJECTIVE
  The flow cytometric evaluation of peripheral lymphocytosis has led to a dramatic increase in the diagnosis of early stage chronic lymphocytic leukemia (CLL) and monoclonal B-cell lymphocytosis (MBL). Few studies exist to better delineate the natural history and differences between MBL and CLL.
  
  
  METHODS
  Applying the recently updated B-lymphocyte threshold of 5 × 10(9) B lymphocytes/L for the diagnosis of CLL, we evaluated the differences in initial presentation, disease progression, time to treatment (TTT), and 10-year overall survival rates between patients with less than 5 × 10 × 10(9)/L, 5 to 10 × 10(9)/L, and more than 10 × 10(9)/L B cells. These clinical/treatment parameters were also compared among the MBL, 5 to 10 CLL Rai stage 0, and more than 10 CLL Rai stage 0 groups.
  
  
  RESULTS
  In total, 310 patients were included, with 67 in the less than 5, 75 in the 5 to 10, and 168 in the more than 10 B-cell groups. Statistically significant differences were seen when comparing the 5 to 10 and more than 10 B-cell groups regarding anemia (P = .021 for median hemoglobin; P = .028 for anemia <11 g/dL), platelet count (P = .041 for median platelet count), splenomegaly (P = .013), initial management plan (P = .012 for observation; P = .0021 for treatment with chemotherapy), and TTT (P = .0033). No statistically significant difference was seen among the MBL, 5 to 10, and more than 10 CLL Rai stage 0 groups regarding TTT and 10-year overall survival.
  
  
  CONCLUSIONS
  Findings suggest that patients with B-cell counts of 5 to 10 × 10(9)/L behave clinically more similar to patients with B-cell counts of less than 5 × 10(9)/L.
authors.affiliation: From the Department of Pathology and Immunology and.
authors.forename: Angela E
authors.initials: AE
authors.lastname: Foster
authors.affiliation: From the Department of Pathology and Immunology and.
authors.forename: TuDung T
authors.initials: TT
authors.lastname: Nguyen
authors.affiliation: Division of Biostatistics, Washington University School of Medicine, St Louis, MO.
authors.forename: Noor
authors.initials: N
authors.lastname: Al-Hammadi
authors.affiliation: From the Department of Pathology and Immunology and.
authors.forename: John L
authors.initials: JL
authors.lastname: Frater
authors.affiliation: From the Department of Pathology and Immunology and.
authors.forename: Anjum
authors.initials: A
authors.lastname: Hassan
authors.affiliation: From the Department of Pathology and Immunology and fkreisel@path.wustl.edu.
authors.forename: Friederike
authors.initials: F
authors.lastname: Kreisel
mesh_terms: D000328:Adult; D000368:Aged; D001402:B-Lymphocytes / Q000166:cytology* / Q000276:immunology; D018450:Disease Progression; D005260:Female; D006801:Humans; D016130:Immunophenotyping / Q000379:methods; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000175:diagnosis*; D018655:Lymphocyte Count; D008218:Lymphocytosis / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D016896:Treatment Outcome
keywords: 10-year survival rate; CLL; Monoclonal B-cell lymphocytosis; Time to treatment