[Familial leukemia]

Occurrence of familial leukaemia confirms the influence of genetic factors in the appearance of malignant diseases. Such cases were described in one generation, in distant relations of two and three generations and in monozygotic siblings. Either the same type of leukaemia was recorded or different types. This is thought to be caused by pathological gene transmission in interaction with environmental factors which increase the tendency to malignant diseases in these families. Two cases of familial type of leukaemia are presented in the paper; in one family the illness appeared among members of one generation, but in the other in two generations. In both families it was a question of acute lymphoblastic leukaemia. Other types of malignancy were not found, nor was any environmental factor confirmed to have influenced cancerogenesis. Cytogenetic studies of the patients did not show any deviation from the normal kariotype. The illness evolution was fatal. This is the second report of familial leukemia in Yugoslav literature.