Cytogenetic studies in 77 patients with chronic lymphocytic leukemia: correlations with clinical, immunologic, and phenotypic data.

Abstract

Cytogenetic analyses by G-banding and/or Q-banding techniques of polyclonal B cell mitogen-stimulated peripheral blood lymphocytes in 77 patients with chronic lymphocytic leukemia were carried out in the present study. Adequate metaphases were obtained in 65 patients (84%). Of 29 patients with abnormal karyotypes, 10 (34%) had trisomy 12 as the sole abormality, 8 (28%) had trisomy 12 in combination with other karyotypic changes, and the remaining 11 had various karyotypic changes other than trisomy 12. There was a significant relationship between the abnormal karyotype and disease status, clinical stage, lymphocyte count, bone marrow infiltration pattern, monoclonal IgM gammopathy, and urinary monoclonal-free light chain status. Six of 7 patients (87%) with trisomy 12 only had stage 0-11 disease, whereas all 8 patients with trisomy 12 with other changes had stage III or IV disease (P < 0.02). Of 9 patients with other karyotypic changes without trisomy 12, 5 had stage 0-11 and 4 had stage III or IV disease. Trisomy 12 may be the primary or the earliest karyotypic change in a majority of aneuploid patients with chronic lymphocytic leukemia, and that other karyotypic changes in addition to trisomy 12 may develop as a result of clonal evolution, dedifferentiation, or therapy. Of 9 patients in whom autopsy studies were carried out, 4 were found to have diffuse histiocytic lymphoma or Richter''s syndrome (3 with trisomy 12 in combination with other chromosome changes and 1 with normal karyotype). Cytogenetic study may be of value in the clinical and prognostic evaluation of patients with chronic lymphocytic leukemia.