1. Department of Obstetrics and Gynecology, Sanggye Paik Hospital, Inje University College of Medicine, Seoul 01757, Republic of Korea
2. Department of Obstetrics and Gynecology, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul 06299, Republic of Korea
3. Molecular Imaging Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
4. Department of Obstetrics and Gynecology, Yonsei University College of Medicine, Seoul 06299, Republic of Korea