Papers discuss the controversies on cytogenetic data and provide a detailed review of oncogenes in relation to B-cell disorders. Specific attention is given to researach studies using tumor promoters and biological modifiers in chronic lymphocytic leukemia. Chronic Lymphocytic Leukemia presents important information on topics such as variants of the disease, prolymphocytic leukemia, T-cell leukemias, Richter's syndrome, and B- and T-cell functions.