Evaluation of novel markers for early detection of colorectal cancer

Interventions: Group 1: Observational Study with diagnostic intervention: the participants will be asked to donate a blood sample, 2 native stool samples and to perform 2 FIT and one Hemoccult test. Primary outcome(s): sensitivity and specificity of tests for the detection of advanced colorectal neoplasia Study Design: Allocation: N/A: single arm study; Masking: Open (masking not used); Control: uncontrolled; Assignment: single; Study design purpose: diagnostic