THE TRANSLOCATIONS, T(11-19)(Q23-P13.1) AND T(11-19)(Q23-P13.3) - A CYTOGENETIC AND CLINICAL PROFILE OF 53 PATIENTS

The EU Concerted Action Workshop on 11q23 Abnormalities in Hematologic al Malignancies collected 550 patients with abnormalities involving 11 q23. Of these, 53 patients had a translocation involving chromosome 11 , breakpoint q23, and chromosome 19, breakpoint p13. Karyogram review enabled each patient to be further defined as t(11;19)(q23;p13.1.) (21 patients) or t(11;19)(q23;p13.3) (32 patients). There was a marked di fference between the type of banding and the translocation identified: t(11;19)(q23;p13.1) was detected predominantly by R-banding, whereas t(11;19)(q23;p13.3) was detected almost solely by G-banding. Additiona l change was extremely rare in patients with t(11;19)(q23;p13.1) but o ccurred in nearly half of the patients with t(11;19)(q23;p13.3). Patie nts with t(11;19)(q23;p13.1) all had leukemia of a myeloid lineage, mo stly acute myeloid leukemia (AML), and were predominantly adult. In co ntrast patients with t(11;19)(q23;p13.3) had malignancies of both myel oid and lymphoid lineage and were mainly infants less than 1 year old. The survival of both groups of patients was generally poor, over 50% of t(11;19)(q23;p13.1) patients died within 2 years of diagnosis and t he median survival of acute lymphoblastic leukemia (ALL) patients with t(11;19)(q23;p13.3) was 17.6 months.