The leukemias is regarded as neoplastic disease characterized by uncontrolled proliferation of haemopoietic cells in the bone marrow and certain other organs, and the appearance of such cells, sooner or later, in the peripherial blood. Different parameters have been used for its classification and nomenclature e.g., clinical duration of the disease, cell type in the blood and vone marrow, and leucocyte count in the peripherial blood film. From the clinical point of view and especially for treatment, the disease is best considered under two heads, acute and chronic, though this is not to minimize the importance of other parameters mentioned above.
This is a medical emergency from the very start of the illness and used to invariably fatal within a year of diagnosis. The past quarter century has, however, seen a remarkable progress in the therapy of acute leukemia. This have been possible chiefly because of:
Availability of drugs
Experience in manipulating various drugs combinations, either sequently or concomitantly, to enhance their therapeutic value.
Recgonization of frequency of central nervous system involvement, its relative refractoriness to conventional treatment and hence its potential for relapses, if local prophylactic treatment is not instituted.
The onset of the disease is usually acute or sub acute with rapidly developing fatigue and general ill-health. Very soon, one or more of the three classical features of acute leukemia become manifest viz. fever, rapidly progressive anaemia and hemorrhages. Other symptoms include marked weakness, diffuse body pain, and ulceration and bleeding from the gums. Presentation with bone and joint pains is much more common in acute lymphoblastic leukemia.
A large number of very potent drugs against acute leukemia have appeared in the last two decades. Many of these are yet not commercially available in developing countries and have to be imported. For this reason patients treated by physicians apecializing in the treatment of acute leukemia in childhood are known to survive considerabely longer then others. Different drug schedules are recommended for acute lymphoblastic and acute myelogenous leukemias, and hence their specific therapy is described separately.