Address of Corresponding Author

Acta Haematol 2005;113:213-219 (DOI: 10.1159/000084673)

  Key Words

• Bone marrow histopathology
• Discriminant analysis
• Essential thrombocythemia
• Polycythemia vera (initial) with thrombocytosis

  Abstract

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.

Copyright © 2005 S. Karger AG, Basel

  Author Contacts

Jürgen Thiele, MD
Institute of Pathology, University of Cologne
Joseph-Stelzmannstrasse 9
DE-50924 Cologne (Germany)
Tel. +49 221 4785008, Fax +49 221 4786360, E-Mail j.thiele@uni-koeln.de

  Article Information

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