1. Department of Gynaecology and Obstetrics; Klinikum Wolfsburg; Wolfsburg Germany
2. Department of Epidemiology and Health Monitoring German Centre for Cancer Registry Data; Robert Koch-Institut; Berlin Germany
3. Health Care Management Unit; Deutsche BKK; Wolfsburg Germany
4. Institute of Pathology; Klinikum Wolfsburg Wolfsburg Germany
5. Gemeinschaftspraxis; Wolfsburg Germany
6. Department of Pathology; Vrije Universiteit Medical Center Amsterdam; Amsterdam The Netherlands