HISTOLOGY AND HISTOPATHOLOGY

Cellular and Molecular Biology

 

Anagrelide does not exert a myelodysplastic effect on megakaryopoiesis: a comparative immunohistochemical and morphometric study with hydroxyurea

J. Thiele1, H.M. Kvasnicka1, S. Ollig1 and A. Schmitt-Gräff2

1Institute of Pathology, University of Cologne, Cologne, 2Institute of Pathology, University of Freiburg, Freiburg, Germany

Offprint requests to: Juergen Thiele, M.D., Institute of Pathology, University of Cologne, Joseph-Stelzmannstr. 9, D-50924 Cologne, Germany. e-mail: j.thiele@uni-koeln.de


Summary. A comparative immunohistochemical and morphometric study was performed on megakaryocytes in 20 patients presenting with initial-early stage chronic idiopathic myelofibrosis and accompanying thrombocythemia to elucidate histological features developing after hydroxyurea (HU) versus anagrelide (ANA) therapy. Representative pre-and posttreatment bone marrow biopsies were involved including the monoclonal antibody CD61 for the identification of precursor and mature stages of megakaryopoiesis. An elaborate morphometric evaluation was in keeping with a left-shifting showing a more frequent occurrence of promegakaryoblasts and microforms in both therapy groups. However, contrasting ANA, HU generated defects of differentiation consistent with significant dysplastic changes. In conclusion, concern about a possible leukemogenic capacity following long-term HU therapy is supported by our findings. Histol Histopathol 20, 1071-1076 (2005)

Key words: Anagrelide, Morphometry, Hydroxyurea, Megakaryopoiesis, Megakaryocyte dysplasia, Immunohistochemistry

DOI: 10.14670/HH-20.1071