ABSTRACT
We studied the clinical and cytogenetic features of 14 acute lymphoblastic leukemia (ALL) patients with 1; 19 translocation. Ten patients had poor prognostic factors such as age over 10 years, hyperleukocytosis over 5 X 10(4)/microliters or high serum lactic dehydrogenase levels over 5,000 IU/l. Two patients had relapsed within 12 months after the onset, but their 5-year survival rate was 84.6%. Cytogenetically, 6 of 14 patients had multiple subclones. Two had the clones with hyperdiploidy greater than 50 chromosomes, which was known to be one of the favorable prognostic factors in childhood ALL. These findings show ALL children with 1; 19 translocation have a more favorable outcome in spite of some high-risk features than hitherto been thought.