Abnormalities in the long arm of chromosome 3 (3q) in myeloid malignancies. Study of 10 cases

BACKGROUND: Abnormalities of the long arm of chromosome 3 (3q) involving ba nds 3q21 and/or 3q26 occur in 2-6% of myeloid malignancies. Trilineage myel odysplasia, especially in the megakaryocytic line, is a characteristic feat ure. Additional abnormalities of chromosomes 5 and 7 are usually present. T he response to treatment and prognosis are poor. PATIENTS AND METHODS: The main clinical, cytologic (bone marrow aspirate an d biopsy) and cytogenetic characteristics as well as the response to the tr eatment in 10 patients with 34 abnormalities diagnosed in a single hospital in a period of 8 years are referred. RESULTS: Eight patients had acute non-lymphoblastic leukemia, being de nova in five of them. The median value of hemoglobin was 87 g/l (range: 51-148) , white blood cells count 5.8 x 10(9)/l (1.2-47.1) and platelet count 34 x 10(9)/l (5-182), The morphological findings in the study of the bone marrow were: dyserythropoietic features (7 patients), dysgranulopoietic abnormali ties (5 patients) and small-sized megakaryocytes with hypolobulated nuclei (8 patients). Fibrosis was observed in the 4 cases in which a bone marrow b iopsy was performed. In addition to the 3q alteration, abnormalities of chr omosomes 7 (4 patients), 5q (2 patients) and +8 (2 patients) were present. Four patients received intensive chemotherapy and in two of them a complete remission was achieved, but relapse occurred at 3 and 5 months, respective ly. All patients have died, the median survival being 7 months. CONCLUSIONS: 34 abnormalities define a subtype of myeloid malignancies with characteristic clinical and morphological features. The response to therap y and survival are poor.