1. Department of Pathology, Rouhani Hospital, Babol University of Medical Science, Babol, Iran
2. Department of General Surgery, Poursina Medical and Educational Center, Guilan University of Medical Sciences, Rasht, Guilan, Iran
3. Department of Pathology, Poursina Medical and Educational Center, Guilan University of Medical Sciences, Rasht, Guilan, Iran
4. Department of General Surgery, Iran University of Medical Science, Tehran, Iran
5. Department of Statistics and Epidemiology, Faculty of Medicine, Babol University of Medical Sciences, Babol, Iran