1. Centre of Postgraduate Medical Education, I-st Department of Obstetrics and Gynecology, 01-813 Warsaw, Poland
2. Department of Genetics, Maria Sklodowska-Curie National Research Institute of Oncology, 00-001 Warsaw, Poland
3. Centre of Postgraduate Medical Education, Department of Gastroenterology, Hepatology and Clinical Oncology, 01-813 Warsaw, Poland