CLINICAL, HEMATOLOGICAL AND MOLECULAR STUDIES IN PATIENTS WITH CHROMOSOME-TRANSLOCATION-T(7-11) - A STUDY OF 4 CHINESE PATIENTS IN TAIWAN

Translocation t(7;11)(p15;p15) is an uncommon but recurrent chromosome aberration in acute myeloid leukaemia (AML), which occurs mostly in o riental patients and in AML M2 or, occasionally, M4 subtype. Recently, a consistent chimaeric fusion transcript NUP98-HOXA9 was found in sev eral cases of t(7;11). Four AML cases with the chromosome abnormality in Taiwan are described, They were all adults with ages ranging from 3 0 to 41 years (median 36 years). Three of them were diagnosed as havin g AML M2; the remaining one as M4. Marked dyserythropoiesis was demons trated in two patients. All four patients showed pan-myeloid antigen C D13 on the leukaemic cells, but none coexpressed lymphocyte-associated antigens and neither of the two patients studied for CD34 expression had positive staining. NUP38-HOXA9 fusion transcript was detected in b oth patients who had molecular analysis and the breakpoints on chromos ome 11 and 7 respectively were similar to those previously reported, T hey all received conventional induction chemotherapy, but only one ach ieved a complete remission (CR) with short duration. This study and ot hers reported in the literature suggest a racial or geographical predi sposition among oriental patients to AML with t(7;11) and that this is associated with a poor prognosis. The molecular detection of NUP98-HO XA9 fusion transcript would be a useful method for the diagnosis of t( 7;11) and also for monitoring disease status after treatment.