Is the histological classification of chronic granulocytic leukaemia justified from the clinical point of view?

Abstract

By means of morphometric techniques, in 100 untreated Ph'-positive chronic granulocytic leukaemia (CGL) patients the main features from the initial bone marrow biopsy were analyzed, with particular attention being paid to morphological and quantitative study of megakaryocytes. The number of megakaryocytes per mm2 of marrow tissue showed a mean value of 25.3 (SD +/- 18.8), and was positively correlated with either platelet counts, blood percentage of basophils and blast cells, or spleen and liver size. Based on the number and morphological characteristics of megakaryocytes, patients were classified as having granulocytic CGL (67 cases) or the so-called chronic megakaryocytic-granulocytic myelosis (33 cases), but except for higher platelet counts and blood percentages of basophils and blast cells in the latter, no relevant clinical, evolutionary or prognostic differences were observed between the groups. Such results cast doubt on the validity of histological classification of CGL from the clinical point of view.