[1] Univ Cologne, Dept Gen Visceral & Canc Surg, Transplant Ctr Cologne, Div Transplantat Surg, Cologne, Germany
[2] Univ Cologne, Inst Med Stat Informat & Epidemiol, Cologne, Germany
[3] Univ Cologne, Dept Ii Internal Med, Cologne, Germany
[4] Univ Cologne, Ctr Mol Med Cologne, Cologne, Germany