The authors reviewed the medical records of 80 patients with monoclonal gammopathy of undetermined significance who were examined at the hospital of Dijon between July 1990 and December 1992. The study included 43 males and 37 females with a mean age of 81.0 +/- 5.5 years. Type of M-component was IgG in 65% of the cases, IgA in 19% and IgM in 13.5%. A biclonal gammopathy was found in 2.5% of the cases. The follow-up duration was 24.6 +/- 10.8 months (range: 1-42 months). The survival probability of patients with monoclonal gammopathy of undetermined significance was 66.6% at 36 months compared with 75.6% in a control population. Lymphoplasmacytic disease developed in four patients (5%). There is a dramatic increase in monoclonal gammopathy with increasing age and the risk of malignant transformation must be continued whatever the age of patients. Further studies are required to determine routine follow-up in the elderly patient with monoclonal gammopathy of undetermined significance until the long term utility and cost/benefit ratio of screening techniques are known.