Studies on blood lymphocytes of patients with nodular poorly differentiated lymphocytic lymphoma

T and B lymphocytes were measured in pretreatment blood samples from patients wih nodular poorly differentiated lymphocytic lymphoma (NPDLL). There were significant differences in T cell values between control groups and patients with NPDLL. In 13 out of 20 cases of NPDLL blood lymphocytes showed abnormalities of immunoglobulin light chain expression and were considered to show an abnormal clonal expansion of B lymphocytes. The abnormal clone of B cells in the blood reflected that found in lymph nodes and could be detected in the absence of bone marrow involvement or blood lymphocytosis.