Colorectal cancer mortality in Spain: trends and projections for 1985-2019

To describe colorectal cancer (CRC) mortality trends during 1985-2004 and to estimate CRC mortality projections for the period 2005-2019 in Spain.

A Bayesian age-period-cohort analysis has been carried out to investigate the effect of the age, period, and birth cohort on CRC mortality in Spain. Mortality projections until 2019 were based on the age-period-cohort model.

During 1985-1994, CRC mortality increased in both sexes (3.9% yearly in men and 1.5% in women). After 1995, CRC mortality increased in men (1.6%) and leveled off in women (-0.6%). Colon cancer mortality increased for the whole period in men, this increase being lower in the second decade (1985-1994: 5.0%; 1995-2004: 1.8%). In women, colon cancer mortality increased in the first decade (2.8%) and leveled off during the second decade (-0.1%). Rectal cancer mortality increased in men (1.2%) and decreased in women (-1.1%) during the whole study period. Projections showed an increase in the number of CRC deaths in men older than 60 years and a level off in women.

Although mass screening for CRC in Spain has not been available, the favorable recent changes in CRC mortality trends observed after 1995 could be related to progress in diagnosis and treatment. The projected number of deaths could be used as reference scenario for assessing future impact of new treatments as well as the potential impact of future population-based screening when introduced.