Increasing incidence of colorectal cancer in the province of Salamanca: comparison of two periods: 2004-2006 and 2010-2012

Objectives: To compare incidence, mortality and epidemiological characteristics of patients diagnosed with colorectal cancer (CRC) in the province of Salamanca over two different periods: 2010-2012 and 2004-2006. Methods: Retrospective observational study. We include all diagnosed cases of CRC according to histopathological criteria from 01/01/2004 to 31/12/2006 and from 01/01/2010 to 31/12/2012. The studied variables were sex, age, date of diagnosis and tumor location. Cumulative incidence and specific incidence in different age groups were measured and compared between the two periods. The age rates were adjusted to the standard world population so that the results could be compared with those of other populations. Results: We detected 38% more cases of CRC in the 2010-2012 period than in 2004-2006. Variables distribution (sex, age at diagnosis and location) was similar in both groups. More than twice as many colonoscopies were performed in 2010-2012 than in 2004-2006. Population mortality due to CRC also increased, although much less importantly than the incidence of this condition. Conclusions: There has been a clear increase in CRC incidence in the province of Salamanca from 2004-2006 to 2010-2012 which is not related to the ageing of the population. The remarkable increase in colonoscopies may have been an important factor for the increased detection.