1. Department of Gynaecological Oncology, Medical University Pleven, 5800 Pleven, Bulgaria
2. Department of General and Clinical Pathology, University Hospital “Dr. Georgi Stranski”, 5800 Pleven, Bulgaria
3. Department of Gynecology, St. Anna University Hospital, Medical University—Varna “Prof. Dr. Paraskev Stoyanov”, 9000 Varna, Bulgaria
4. Imaging Department, University Hospital “Dr. Georgi Stranski”, 5800 Pleven, Bulgaria
5. “Dr. Shterev” Hospital, 1000 Sofia, Bulgaria