3q Chromosomal Abnormalities Associated with Dysmegakaryopoiesis in Acute Leukemias

Lee, Yong Wha; Lee, Kyung A; Kim, Sun Hee

Abstract

BACKGROUND
Abnormalities of chromosome 3q21-26 in patients with hematologic malignancies have been suggested to be associated with normal or elevated platelet counts and abnormal megakaryopoiesis. However, the relationship and pathogenic mechanisms are not yet clear. Therefore, we have attempted to clarify the relation of the chromosome 3q abnormalities with dysmegakaryopoiesis in 23 leukemia patients.
METHODS
We reviewed retrospectively bone marrow studies, cytogenetic analyses and clinical records of 229 patients with leukemia (AML, ALL or CML in blastic crisis) between 1995 and 1999 with the emphasis on thrombocytopenia, chromosome 3q abnormalities, and dysmegakaryopoiesis in bone marrow.
RESULTS
Among 229 leukemia patients, 9 patients (3.9%) had chromosome 3q abnormalities, 11 (4.8%) had dysmegakaryopoiesis and 13 (5.7%) showed normal to increased platelet counts. The platelet count of 9 patients with chromosome 3q abnormalities ranged from 7x109/L to 1623x109/L and 6 of them had decreased numbers of platelets and megakaryocytes, and two patients had dysmegakaryopoiesis. Among them, three patients had an increased number of megakaryocytes with dysmegakaryopoiesis and showed t (2; 3)(q31; q25) or inv (3)(q21q26). They showed a good response to standard chemotherapy. 8 of 10 patients, but neither thrombocytopenia nor chromosome 3q abnormalities, had normal or an increased number of megakaryocytes.
CONCLUSIONS
No major prognostic influence was found due to the presence of large numbers of dysplastic megakaryocytes and normal to increased platelet counts in acute leukemia and seemingly were not uniquely associated with changes involving chromosome 3q and abnormalities of 3q21 and 3q26 associated with dysplastic megakaryocytes.