The leukaemias are a heterogeneous group of malignant blood disorders. In this introductory section, general characteristics such as definitions, aetiology and classification are discussed. Each of the more common types of leukaemia is subsequently described in more detail.


Leukaemia is not a common disorder but it is a significant cause of death from cancer (Fig 19.1). There is a male preponderance in most types of leukaemia. Geographic variations exist; for instance, chronic lymphocytic leukaemia is the predominant form of leukaemia in the Western world but is much less frequent in Japan, South America and Africa.


As for other malignancies, the evolution of leukaemia is likely to be a multistep process. Thus, accumulated genetic mutations corrupt normal cellular pathways controlling proliferation and differentiation and lead to the production of an autonomous proliferating stem cell clone (‘clonal evolution’). It is easiest to think about the aetiology in terms of these acquired genetic abnormalities and other more general predisposing factors.

Genetic abnormalities

Cytogenetic analysis and particularly molecular genetic techniques have revealed various acquired non-random chromosomal derangements which play a fundamental role in leukaemogenesis (Fig 19.2). There are a number of different types of possible chromosomal change.

Jun 12, 2016 | Posted by in HEMATOLOGY | Comments Off on Introduction

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