6 patients with non-Hodgkin's lymphoma [3 with small cell lymphocytic lymphoma of B-cell type (SL), and 1 each with follicular centroblastic/centrocytic, centroblastic, and immunoblastic lymphoma] and with the acquired cytogenetic abnormalities del(14) (q22) or del(14) (q24) are described. An evaluation of these 6 cases and 41 other lymphatic neoplasms with 14q deletion known from the literature revealed that 37 had a breakpoint in bands q22 to q24. The deletions occur significantly more often in lymphomas of SL morphology and in the leukemic counterpart, chronic lymphocytic leukemia, than in other types of lymphatic malignancies (p less than 0.001).