Acute leukemia with abnormal thrombopoiesis and inversions of chromosome 3.

Abnormal thrombopoiesis has been described in acute leukemias associated with inv(3) (q21q26.2) or t(3;3)(q21;q26.2). We reviewed 13 patients seen at the Mayo Clinic since 1979 with inversions of chromosome 3 or related abnormalities; 12 acquired and one constitutional. The patient with the constitutional abnormality had an inv(3)(p21q29) and mild leukocytosis and thrombocytosis. Among the 12 patients with acquired abnormalities, five had inv(3) (q21q26.2), three had t(3;3)(q21;q26.2), one had del(3)(q12q21), one had ins(6;3) (p21;q21q26.2), one had inv(3)(p21q12), and one had r(3)(p?21q?21). Each of these patients developed acute leukemia; eight had antecedent myelodysplastic syndrome, eight presented with platelet counts greater than 100 x 10(3)/microliters, and six had atypical megakaryocytic hyperplasia. Five patients had ringed sideroblasts in their marrow, an antecedent refractory anemia with ringed sideroblasts, or erythroleukemia. Seven patients received chemotherapy but showed no response. From the time of chromosome study, the median duration of survival was 4 months. Our results suggest that 1) although abnormal megakaryocytopoiesis is observed in patients with inv(3)(q21q26.2), multiple hematopoietic lineages are also involved in the neoplastic process; 2) an antecedent myelodysplastic syndrome is common in acute leukemia with inv(3) or related abnormalities; 3) affected patients have a poor survival and are resistant to conventional chemotherapy; and 4) abnormal megakaryocytopoiesis in acute leukemia may also be associated with pericentric inversions of chromosome 3.