1. Department of Histopathology; Medical University of Silesia; ul. Medyków 18 40-754 Katowice Poland
2. Department of Epidemiology; Medical University of Silesia; ul. Medyków 18 40-754 Katowice Poland
3. Department of Pathology; Victoria Hospital; Whinney Heys Road Blackpool FY3 8NR UK
4. Department of Gastrointestinal Surgery; Medical University of Silesia; ul. Medyków 18 Katowice 40-754 Poland