Chronic lymphatic leukaemia: correlation of immunofluorescent characteristics and clinical features

60 patients with chronic lymphatic leukaemia (CLL) were classified according to the immunofluorescent characteristics of their lymphocytes. A group expressing surface membrane (Sm) IgM had a significantly less aggressive disease than those expressing a mixture of SmIgM and SmIgD or those without surface immunoglobulin. The patients were older than in most comparable series and had a 2:I preponderance of women. It is suggested that especially among old ladies there is a benign variety of CLL which expresses SmIgMK, and that determination of the SmIg class in CLL has prognostic value.