title: Hematopoietic progenitor cell colony growth differentiates chronic myelomonocytic leukemia from reactive monocytosis.
abstract: In the absence of a cytogenetic abnormality or overt dysplasia, chronic myelomonocytic leukemia (CMML) may be difficult to be distinguished from reactive monocytosis. We have previously described a typical growth pattern in CMML patients, i.e., 'pseudonormal' colonies resembling granulocytic colonies but consisting entirely of monocytic cells when stained. To study the utility of the colony forming unit cell assay (CFU-C) as a diagnostic tool in patients with monocytosis, we analyzed a cohort of 48 consecutive patients referred to our institution with peripheral blood monocytosis. Thirty-six patients fulfilled the WHO criteria for CMML; 12 were diagnosed with reactive monocytosis. Of the patients with CMML, 28 showed pseudonormal growth with or without leukemic cluster growth, another four showed exclusively leukemic growth. None of the patients with reactive monocytosis showed either leukemic or pseudonormal growth. With a specificity of 100% and a sensitivity of 89%, the CFU-C assay has a unique potential to distinguish CMML from reactive monocytosis.
authors.affiliation: Department of Hematology, University Hospital, Basel, Switzerland.
authors.forename: Angelika
authors.initials: A
authors.lastname: Birrer
authors.forename: Florije
authors.initials: F
authors.lastname: Jusufi
authors.forename: Michael
authors.initials: M
authors.lastname: Bernimoulin
authors.forename: André
authors.initials: A
authors.lastname: Tichelli
authors.forename: Alois
authors.initials: A
authors.lastname: Gratwohl
authors.forename: Catherine
authors.initials: C
authors.lastname: Nissen-Druey
authors.forename: Stephan
authors.initials: S
authors.lastname: Dirnhofer
authors.forename: Sandrine
authors.initials: S
authors.lastname: Meyer-Monard
authors.forename: Martin
authors.initials: M
authors.lastname: Stern
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D003114:Colony-Forming Units Assay; D003937:Diagnosis, Differential; D005260:Female; D006412:Hematopoietic Stem Cells / Q000473:pathology; D006801:Humans; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000175:diagnosis* / Q000473:pathology; D007964:Leukocytosis / Q000175:diagnosis* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000473:pathology*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity