Initial (Latent) Polycythemia vera with Thrombocytosis Mimicking Essential ThrombocythemiaThiele J. · Kvasnicka H.M. · Diehl V.
aInstitute of Pathology and bFirst Clinic of Internal Medicine, University of Cologne, Cologne, Germany
Patients have previously been described who showed clinical signs and symptoms suggesting essential thrombocythemia (ET), but later transformed to polycythemia vera (PV). From a series of 344 patients with a sustained borderline to moderate erythrocytosis, 44 failed to conform initially with the diagnostic criteria of the WHO for PV, because of their low hemoglobin level. Twenty-three patients of this group presented with a thrombocytosis exceeding 600 × 109/l and therefore suggested ET, but later developed full-blown PV. For comparison we investigated also 164 patients with manifest PV, 90 patients with ET and 22 patients with reactive thrombocytosis (Th). The histopathology of initial PV was evaluated by stepwise discriminant analysis of 17 standardized features. Quantity and left shifting of erythro- and granulopoiesis, giant forms and naked nuclei of megakaryocytes, cellularity and reticulin fibers proved to exert a significant relevance concerning differentiation from true ET and Th. In conclusion, initial PV with thrombocytosis is characterized by a special pattern of BM histopathology. Therefore, so-called masked PV in patients with ET or simultaneous PVR-1 gene expression and endogeneous erythroid colony growth in ET patients are probably in keeping with initial PV mimicking ET.
Jürgen Thiele, MD
Institute of Pathology, University of Cologne
DE–50924 Cologne (Germany)
Tel. +49 221 4785008, Fax +49 221 4786360, E-Mail email@example.com
Received: October 7, 2004
Accepted: October 25, 2004
Number of Print Pages : 7
Number of Figures : 2, Number of Tables : 3, Number of References : 40
Vol. 113, No. 4, Year 2005 (Cover Date: June 2005)
Journal Editor: Ben-Bassat, I. (Tel Hashomer)
ISSN: 0001–5792 (print), 1421–9662 (Online)
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