[Leukemic chromosome clone. I. Risk factor in the acute lymphatic leukemia of children]

As long as the aetiology of acute lymphatic leukaemia of children is not known its therapy is based on clinical experience. Among the values of experience those factors will play a part, the evidence of which during the ALL initial stage will be a risk for successful therapy and survival rate. This results in a choice of more aggressive variants of modern therapy schemes. In a cytogenetic study made in 35 children with ALL it was tested, whether even leukaemic chromosome clones will be a risk for the course of acute leukaemia. The duration of the first remission and survival rate were considered as criteria. The evidence of a leukaemic chromosome clone could be shown to be followed by a short survival rate, irrespective of the stage of the disease where the clone had been observed first. Thus, cytostatic therapy in those ALL patients who are affected with luekaemic chromosome aberration of stem line character should be aimed at the complete annihilation of the clone, irrespective of other remission criteria. The failure of blood and bone-marrow cultures as early as during the untreated initial stage indicated a primary cellular immuno-insufficiency. This combination of cell immuno-depression with high peripheral leukocytes connts and a primary mediastinal tumour or a generalizing lymphosarcoma respectively, was the highest risk up till now for the course of the disease. Judging from the duration of the first remission and the survival rates, the consecutive schemes of therapy did not differ in their effect on leukaemia with pathological stem lines. On the basis of the present study the impression could not be excluded that up till now long term survival rates could be attributed rather to individual manners of response than to the modern therapy scheme.