[The risk of a multiple myeloma in patients with paraproteinemia: a myeloma risk score developed in the region of the Comprehensive Cancer Center West].

Diagnoses in patients with paraproteinaemia are diverse; few (mostly single centre based) studies are known that describe incidence, diagnoses and follow-up in patients with paraproteinaemia. In the region of the Comprehensive Cancer Centre West in the Netherlands (population 1.6 million, 1992) a population-based registry was set up in the period 1991-1993. Patients (n = 1464; median age: 72 years; range: 16-102) were entered by clinical chemists, internists, haematologists, and pathologists. Multiple myeloma and plasmacytoma were diagnosed in 261 patients (18%), paraprotein-related haematological diseases in 159 patients (11%) and paraprotein-related internal diseases in 210 patients (14%). After bone marrow examination monoclonal gammopathy of unknown significance (MGUS) was diagnosed in 207 (14%) patients. No further diagnosis could be made in 627 (43%) patients mostly for lack of supplementary bone marrow and (or) X-ray examinations. Consequently, more than two-thirds of all patients with a newly found paraprotein did not show any sign of a haematological malignancy. Using these data a 'myeloma risk score' was developed to predict the presence of a multiple myeloma based on paraprotein type and concentration, aiding the physician in determining which patients should undergo further bone marrow and skeletal examinations.