DELETION-20Q IN ASSOCIATION WITH PHILADELPHIA-CHROMOSOME-POSITIVE ACUTE LYMPHOBLASTIC-LEUKEMIA - A REPORT OF 2 CASES

Cytogenetic deletions involving the long arm of chromosome 20 are thou ght to be characteristic of myeloid disorders. We report clinical and cytogenetic observations of two adult patients with Philadelphia chrom osome positive acute lymphoblastic leukemia: one with a smaller 20q de letion that was the sole cytogenetic abnormality in a persisting remis sion clone, the other with a larger 20q deletion that was a late addit ion to the leukemic clone at disease relapse following allogeneic bone marrow transplantation.