Multiple myeloma: epidemiological features in a well-defined population in Burgundy, France

Epidemiological features of multiple myeloma were studied over a seven-year period (1980-86) in the department of Côte d'Or (population 478,000). The crude annual incidence rates were 3.7/100,000 for males and 4.0/100,000 for females. The corresponding age-standardized rates were 2.5 and 2.1. The sex ratio was 1.2. Cumulative rates were 0.3% for both sexes. Age and specific incidence were low before 50 and increased with advancing age up to 85 years in males and females. There was no significant variation in incidence over the seven-year period. The risk of multiple myeloma was slightly higher in urban than in rural areas (the variations were not significant). The period between the beginning of the symptoms and the diagnosis was often short, less than one month in 56% of the cases. When compared to other population based registries the incidence rates are similar to those reported all over the world (except for registries with a high proportion of blacks in the population). Cases have been staged according to Durie and Salmon classification: 32% of the cases were classified as Stage I. This result suggests that globally cases diagnosed in a well-defined population are less severe than those reported in hospital statistics. Survival showed significant differences: there were better rates for patients under 75 and for patients at stage I and II compared with stage III patients. Percentage and morphology of plasma cells also influenced prognosis.