Unclassifiable Leukemias : Proceedings of a Symposium, Held on October 11 - 13, 1974 at the Institute of Cell Pathology, Hopital De Bicetre, Paris, France.

Jean BERNARD \* I should like to begin with an assumption and a paradox. The assumption is that leukemia is a disease of a stem cell characterized by pathologie alterations of that cell and its progeny. All present research and discussions are centered around the leukemic cell. So is this symposium, which would not take place except for our primary interest in the leukemic cell. This does not preclude, of course, consideration of other definitions and other approaches to the prOblem. By definition, then, the leukemic cells are abnormal cells and their metabolism and functions are presumed to be abnormal. Yet, the classification of the different types of leukemias is based upon the characteristics of normal cells. We talk of "lymphoblasts" and "myeloblasts" as predominant cell types in leukemia. This leads to a double paradox. In the first pi ace it is clearly illogical to classify abnormal cells by their resemblance to normal cells, since their very abnormality consists in not being normal. Yet, as a second paradox, the classifica­ ti on has had the happy consequence of ai ding us in the treatment and prognosis of leukemia for the past 25 years. A more detailed analysis shows that the consequence of this paradox are complex: while there exists a useful correlation between cellular types, treatment and prognosis, numerous problems and difficulties persist. The most serious of them concems the "unclassified leukemias" which are the reason for this reunion. Front Matter....Pages I-VIII Front Matter....Pages 1-1 Introduction....Pages 3-5 Cytological Classification of Acute Leukemias A Survey of 1400 Cases....Pages 7-15 Classification of the Acute Leukaemias....Pages 17-24 Leukaemic Lymphosarcomas: Respective Prognosis of the Three Types: Prolymphocytic, Lymphoblastic (or Lymphoblastoid) and Immunoblastic....Pages 25-36 Search for Correlations between Cytological Types and Therapeutic Sensitivity of Acute Leukaemias....Pages 37-52 Answers to Submitted Questions....Pages 53-56 Open Discussion of Section I....Pages 57-60 Front Matter....Pages 61-61 Fluorescence Probe and Biochemical Characterization of Leukaemic Cells....Pages 63-65 Discussion....Pages 67-70 Automated Cell Population Analysis....Pages 71-77 Discussion....Pages 79-80 The Use of B and T Membrane Markers in the Classification of Human Leukemias, with Special Reference to Acute Lymphoblastic Leukemia....Pages 81-90 Discussion....Pages 91-94 Volumetric Determinations of Blood Cells in Acute Lymphoblastic Leukemia....Pages 95-97 Discussion....Pages 99-99 Acute Leukemia Cytochemical Profile: Diagnostic and Clinical Implications....Pages 101-108 Discussion....Pages 109-113 B, T and “null” Cell Leukaemias....Pages 115-124 Discussion....Pages 125-127 Giant Platelet Granules in Refractory Anemia (Preleukemia) and Myelomonocytic Leukemia: a Cell Marker?....Pages 129-135 Front Matter....Pages 61-61 Discussion....Pages 137-138 Inhibition of Time-dependent Enhancement of Amino Acid Transport by Leukemic Leukocytes: A Possible Index of the Sensitivity of Cells to Drugs....Pages 139-146 Discussion....Pages 147-147 Marrow Culture—a New Approach to Classification of Leukemias....Pages 149-158 Discussion....Pages 159-160 Cytogenetic Studies of Marrow and Peripheral Blood Granulocyte Colonies in Treated Chronic Myelogenous Leukemia....Pages 161-162 Cytogenetic Studies in Preleukemia: Studies before and after Transition to Acute Leukemia in 17 Subjects....Pages 163-170 Discussion....Pages 171-172 Correlated Cytogenetic and Ultrastructural Studies in Acute Leukemia....Pages 173-175 Discussion....Pages 177-179 Front Matter....Pages 181-181 Pathology of the Leukemic Cell or Reasons Why Some Leukemias are Unclassifiable....Pages 183-188 Discussion....Pages 189-190 Abnormal Neutrophils in Acute Myelogenous Leukemia: Identification of Subpopulations Based on Analysis of Azurophil and Specific Granules....Pages 191-199 Significance of Cell Differentiation in Acute Myeloid Leukaemia....Pages 201-211 Discussion....Pages 213-215 Different Cell Proliferation Models in Myeloblastic and Lymphoblastic Leukaemia....Pages 217-222 Discussion....Pages 223-225 Clonal Evolution and Progression in Chronic Myeloid Leukaemia....Pages 227-234 Discussion....Pages 235-237 Variations of the Proliferative Activity of Leukemic Myeloblasts Related to the Stage of the Disease....Pages 239-248 Front Matter....Pages 181-181 Discussion....Pages 249-251 Front Matter....Pages 253-253 Summing Up....Pages 255-256 Summing Up....Pages 257-258 On Classification of Leukemia....Pages 259-262 General Discussion....Pages 263-267 Back Matter....Pages 269-270