Colchicine ultrasensitivity of peripheral-blood lymphocytes from patients with non-Hodgkin's lymphoma.

Incubation for 20 h in low concentrations of colchicine has been shown to kill the peripheral blood lymphocytes (PBL) of patients with chronic lymphocytic leukaemia (CLL), whereas at least a 10,000 x higher concentration of colchicine is required to kill lymphocytes from a normal donor. This ultrasensitivity of CLL lymphocytes to low doses of colchicine was confirmed in 19/20 PBL samples, 5/6 lymph nodes, and in the one totally replaced marrow studied. PBL from 75 patients with non-Hodgkin's lymphoma (NHDL) were examined for colchicine ultrasensitive (CUS) cells similar to those found in CLL. All the patients had less than 5 x 10(9)/1 morphologically normal circulating lymphocytes. PBL from 45 healthy donors and 39 patients with diseases other than leukaemia or lymphoma were used as controls. CUS cells were detected in 24 (32%) of the 75 patients. The CUS cells were considered to represent blood involvement with malignant lymphocytes for three reasons. First, there was an association with marrow involvement (P less than 0.05) which usually accompanies involvement of the blood with morphologically abnormal cells. Secondly, 23 (77%) of the 30 involved lymph nodes, marrows and spleens studied were CUS. Thirdly, there was a close correlation with the presence of a monoclone of B lymphocytes demonstrated by surface markers (P less than 0.01).