ABSTRACT: Interventions: Group 1: Other study, single-arm, with performance of colonoscopy (patients for screening, screening and diagnostic) to investigate the prevalence of colorectal neoplasia, including colorectal cancer, advanced adenoma or sessile jagged polyps > 1 cm, using a cross-section of the general population aged 30-49 years. Prior to colonoscopy, biosamples of blood, urine, saliva, stool are taken in order to gain insights into biomarkers. Questions about lifestyle and health behaviour are asked in 2 online questionnaires. The questionnaires contain building blocks of internally validated questionnaires or from internal studies such as DARIO, GEKKO, RAPS as well as from the questionnaires of the NAKO study and the GPAQ questionnaire (https://www.who.int/ncds/surveillance/steps/GPAQ_German.pdf).
The participants (TN) will be invited in writing to participate in study part 1 and to take part in the first online questionnaire.
If the inclusion criteria are fulfilled and no exclusion criteria apply, the participant will be invited in writing to study part 2 and will receive the access code for the online questionnaire2. If interested, the participant will make an appointment for a colonoscopy and biosample collection on site at the LEO study center. This appointment lasts about 45 minutes. If interested, the appointment for a colonoscopy will be arranged. This takes place at the Interdisciplinary Endoscopy Center (IEZ) of the medical clinic in Heidelberg. The colonoscopy is performed according to the guidelines and time schedule of the clinic.
Primary endpoint:
The prevalences of advanced colorectal neoplasms including colorectal cancer, advanced adenoma or sessile serrated polyp > 1 cm.
This will be assessed in a cross section of the general population aged 30-49 years with no previous early detection examination for colorectal cancer through the gold standard, colonoscopy and in addition according to levels of polygenic risk scores or genetic risk scores (PRS).
PRS, based on multiple SNPs have recently been shown to be potentially very powerful tools for risk stratification far beyond the risk information based on self-reported family history of CRC or other established CRC risk factors.
Given that PRS is a continuous trait with no natural cutpoint”, we will classify participants according to quartiles of the PRS in the primary analysis, but additional analyses will be conducted to explore predictive ability and dose-response relationships across the entire range of PRS levels.
A biobank will be set up in order to evaluate the PRS and further biomarkers or biomarker signatures that may be useful, by themselves or in combination with each other or the PRS, for early detection of advanced colorectal neoplasms or risk stratification in colorectal cancer screening.
In addition, 2 questionnaires, which ask about lifestyle and general health, are used for risk stratification.
Study Design: Allocation: N/A: single arm study; Masking: Open (masking not used); Control: uncontrolled; Assignment: single; Study design purpose: screening
