THE COMBINATION of mongolism and leukemia in the same patient would be expected, by chance alone, to occur in 1 of 10 million children in the age range 0 to 4 years. Krivit and Good1 calculated these figures from the frequency of mongolism of 1 per 500 live births,2 and leukemia deaths of about 5 per 100,000 in the same age range.3 Stewart and co-workers4 showed that combined mongolism and leukemia was approximately 20 times more frequent than expected. It is probable that in addition to mongolism with trisomy-21 or equivalent, the risk of malignant disease may be increased in other disorders with genic imbalance resulting from abnormal karyotypes.5,6 Cases of mongolism and leukemia in the same family have also been described.7-11
This report describes chromosomal studies on eight mongoloids in whom a diagnosis of leukemia was made. The clinical courses and hematological findings