1. Department of Gastroenterology and Hepatology; University Hospital; University of Duisburg-Essen; Essen Germany
2. Medizinisches Proteom-Center; Ruhr-Universität Bochum; Bochum Germany
3. Leibniz Institute for Analytical Sciences - ISAS; Dortmund Germany
4. Department of Pathology and Neuropathology; University Hospital of Essen; Essen Germany
5. Department of General, Visceral and Transplantation Surgery; University Hospital of Essen; Essen Germany
6. Department of Medicine (Cancer Research); Molecular Oncology Risk-Profile Evaluation; University Hospital of Essen; Essen Germany