1. Department of Oncology and Hematology, University of Cologne, D‑50937 Cologne, Germany
2. Department of Visceral Surgery, University of Cologne, D‑50937 Cologne, Germany
3. Institute of Pathology, University of Cologne, D‑50937 Cologne, Germany
4. Institute of Pathology, Pammukale University, Denizli 20160, Turkey