Trends of incidence, mortality and survival of multiple myeloma in Spain. A twenty-three-year population-based study

Background Despite major advances, multiple myeloma remains an incurable disease. Epidemiological data from high-quality population-based registries are needed to understand the heterogeneous landscape of the disease. Methods Incidence, mortality and survival in multiple myeloma were comprehensively analyzed in the Girona and Granada population-based cancer registries, over a 23-year study (1994-2016), divided into three periods (1994-2001, 2002-2009 and 2010-2016). Joinpoint regression analysis was used to estimate the annual percentage change in incidence and mortality. Age-standardized net survival was calculated with the Pohar-Perme method. Results 1957 myeloma patients were included in the study, with a median age of 72 years. Age-standardized incidence and mortality rates decreased over time in both sexes and both rates were higher in males. Five-year age-standardized net survival by period was 27.4% (1994-2001), 38.8% (2002-2009), and 47.4% (2010-2016). Survival improved for all age groups: 32.4%, 74.1% and 78.5% for patients aged 15-49; 27.5%, 44.6%, and 58.5% for those aged 50-69; finally, 24.8%, 25.5%, and 26.3% for the older group. Conclusion Incidence remained overall stable throughout the study, with only a small increase for men. Mortality was progressively decreasing in both sexes. Both incidence and mortality were higher in men. Age plays a critical role in survival, with impressive improvement in patients younger than 70 years, but only a minor benefit in those older than 70.