[Lesions Detected in Six Spanish Colorectal Cancer Screening Population Based Programmes. CRIBEA Project. Spain]

In this study, the results of six Colorectal Cancer Screening Population Programmes are shown (Catalonia, Valence, Murcia, Cantabria, the Basque Country and the Canary Islands collected between 2005 and 2012. These programmes use the faeces occult blood test (FOBt) biennial. Objective: To determine and compare the results of lesions detected by the programmes, participation, sex, age and test used.

Retrospective cohort study based on people invited, aged between 50-74 years, in at least a complete round. Lesions considered: Advanced Adenomas (AA), Colorectal Invasive Cancer (CRC) and both of them, known as Advanced Neoplasia (AN). Logistic Regression and time trends are used.

1,995,719 of invitations registered, with an average participation-rate of 46.7%. 21,228 Advanced Neoplasias (2,813 CRC and 18,415 AA). Differences in detection rates observed between programmes (varying from 15.1‰ to 35.8‰ between participants). Participation rates were related to lesions' detection rates (OR 1.25 in 40-60% of participation). . Inmunochemical qualitative test showed an OR of 4.79 and quantitative test an OR of 7.30 over the guaiac test. Men showed an OR of 2.73 with respect to women. In 2012 the Advanced Neoplasia rate for women and men was 33.1 and 14.2 by 1,000 participants.

The test used was the most important factor for detecting lesions. Time trends showed an increase in detected lesions caused by the change of the type of test in 2010.