Analysis of tumor DNA markers in the plasma of colorectal cancer patients by liquid biopsy

Interventions: Group 1: Blood and sputum samples as well as paraffin embedded tumour tissue from patients with microsatellite stable colorectal cancer shall be analysed before therapy and over time to establish and validate hotspot mutation and somatic copy number variant (SCNAs) analysis. We therefore need the following samples:
- Two Cell-Free DNA BCT CE Streck tubes with 8 ml blood per sampling for preparation of plasma-DNA.
- One sputum tube (only at study inclusion).
- FFPE tissue samples from the primary tumor (from initial surgery)
Group 2: Blood samples of tumor-free control persons shall be tested for hotspot mutations and somatic copy number variants (SCNAs) to identify technical artefacts and improve our protocols. We therefore need the following samples:
- Two Cell-Free DNA BCT CE Streck tubes with 8 ml blood per sampling for preparation of plasma-DNA.
Primary outcome(s): Identification of tumorspecific SCNAs in plasma samples of colorectal cancer patients
Study Design: Allocation: ; Masking: ; Control: ; Assignment: ; Study design purpose: other