X-CHROMOSOME AND Y-CHROMOSOME LOSS AS SOLE ABNORMALITY IN ACUTE NONLYMPHOCYTIC LEUKEMIA (ANLL)

Of the 9300 bone marrows and peripheral bloods analyzed for hematologic disease in our laboratory between 1978 and 1990, 240 patients exhibited X or Y loss of chromosomes. Of those 240 patients only two could be positively associated with acute leukemia and no other observable chromosome involvement. The evidence presented here, albeit represented by only two patients, proves that sex chromosome loss as the sole abnormality can be a clonal cytogenetic marker far acute leukemia. One patient was a 48-year-old man with loss of the Y in 93% of his bone marrow metaphases and the other patient was a 53-year-old woman with 100% loss of the X in her bone marrow metaphases (perhaps the first such report of a woman). After therapy, both remission bone marrow analyses showed complete reappearance of the respective sex chromosomes.