Marja Ekblom

Chromosome abnormalities in 16 finnish patients with Burkitt's lymphoma or l3 acute lymphocytic leukemia☆

Eleven patients with Burkitts lymphoma (BL), i.e., small noncleaved non-Hodgkins lymphoma, and 5 patients with Burkitt-type acute lymphocytic leukemia (ALL-L3) were selected for chromosome study. Two of the 16 patients had no B-cell markers, but the erythrocyte marker--glycophorin A--was present on the surface of the leukemic blasts. The critical breakpoint at 8q24 was detected in 14 of the 16 patients, whereas this aberration was not detected in any of the 134 patients belonging to other subgroups of non-Hodgkins lymphoma or ALL that we studied during the same period. In addition to the t(8;14)(q24;q32), the following translocations with the breakpoint at 8q24 were seen: t(2;8)(p11;q24), t(8;11)(q24;q13) in BL, and t(2;8;14)(p11 or p12;q24;q32) in ALL. Additional aberrations seen more than once were trisomy #7 and abnormalities in chromosomes #1, #11, and #13.

Critical chromosome rearrangement in acute promyelocytic leukemia

We report here a patient with acute promyelocytic leukemia (APL) who has two normal chromosomes #15 but a structurally abnormal chromosome #17. This case indicates that the critical point of rearrangement in APL is not necessarily in chromosome #15 but may, alternatively, be in chromosome #17.