[Comparative clinical and histological investigations in chronic myeloid leukaemias ]

76 cases of CML were divided according to clinical parameters (duration of illness prior to diagnosis, size of spleen, leucocyte and platelet counts, ALP index, bone marrow cytology and others) into groups showing a classical or an atypical course of the disease. All patients were submitted to bone marrow biopsy, using the method of Jamshidi and Swaim. The histological subtypes of CML, i.e. chronic granulocytic leukaemia and chronic megakaryocytic granulocytic myelosis were correlated with the two clinical types of disease. The classical form of CML was histologically inhomogeneous and was subdivided into 40% cases of chronic granulocytic leukaemia and 60% cases of chronic megakaryocytic granulocytic myelosis. At the time of bone marrow biopsy 20% of patients with classical leukaemia were already found to have myelofibrosis. The atypical myeloses consisted of chronic megakaryocytic granulocytic myelosis only and myelofibrosis was present initially in 50% of patients. In view of these findings agnogenic myeloid metaplasia is considered to be merely a variant of chronic myeloid leukaemia and the term "atypical myelosis" is preferred.