Cytogenetics and flow in diagnosis of myeloproliferative disorders.
Posted Jun 24 2009 7:01pm
Chronic myeloproliferative disorders (CMPD) are classified according to the WHO classification of 2001 as polycythemia vera (PV), chronic idiopathic myelofibrosis (CIMF), essential thrombocythemia (ET), CMPD/unclassifiable (CMPD-U), chronic neutrophilic leukemia, and chronic eosinophilic leukemia (CEL)/hypereosinophilic syndrome, all to be delineated from BCR/ABL-positive chronic myeloid leukemia (CML). I consider both cytogenetics and flow as not med. appropriate for diagnosis of CMPD. Clonal aberrations are found in 10% of patients with suspected CMPD establishing the diagnosis of a malignant disease but not allowing a secure diagnosis of any particular type of CMPD. A bone marrow would need to be repeated for that to be accomplished.
Cytogenetics are potentially more useful but only if they demonstrate a phildelphia chromosome. Nowadays, PCR for BRC/ABL is the prefered test to do that and it can be performed on the marrow as well as blood. While some recent articles claim that one or another combination of cytigenetics and flow with other factors can diagnose CMPD, this has not been confirmed in prospective studies or recommended by guidelines. JAK2 mutation is more valuable than either of these two tests.
Kern W, Hiddemann W, Schnittger S, Schoch C.Conventional cytogenetics of myeloproliferative diseases other than CML contribute valid information, Ann Hematol. 2005 Apr;84(4):250-7. Epub 2005 Feb 4.