KARYOTYPE ABNORMALITIES AND THEIR CLINICAL-SIGNIFICANCE IN BLAST CRISIS OF CHRONIC MYELOID-LEUKEMIA

We examined karyotypes and their prognostic significance in a series o f 122 patients with chronic myeloid leukemia in blast crisis, Of 73 pa tients cytogenetically examined at the onset of blast crisis 63% had d eveloped secondary cytogenetic abnormalities in addition to the Philad elphia chromosome. These newly emerging abnormalities included a doubl e Philadelphia chromosome in 20 patients, a trisomy 8 in 17, ansi an i sochromosome 17q in 11 patients. Development of such additional karyot ypic abnormalities was significantly associated with a shorter median survival and less response to cytoreductive treatment and was signific antly more common in nonlymphoid blast crisis than in the lymphoid-typ e blast crisis, Thus, assessment of karyotypes at the onset of chronic myeloid leukemia blast crisis appears to be of prognostic significanc e for both remission duration and survival.