1. Department of Gynecology, Kitasato University School of Medicine, Sagamihara, Japan
2. Department of Obstetrics and Gynecology, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan
3. JCOG Data Center, Multi-institutional Clinical Trial Support Center, National Cancer Center, Tokyo, Japan
4. Gynecology Service, National Kyushu Cancer Center, Fukuoka, Japan
5. Department of Gynecology, National Cancer Center Hospital, Tokyo, Japan
6. Department of Gynecologic Oncology, Aichi Cancer Center Hospital, Aichi, Japan
7. Department of Gynecology, National Shikoku Cancer Center, Matsuyama, Japan
8. Department of Obstetrics and Gynecology, The Jikei University School of Medicine, Tokyo, Japan
9. Department of Obstetrics and Gynecology, Kurume University School of Medicine, Kurume, Japan
10. Department of Gynecology and Obstetrics, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
11. Department of Gynecology, Tohoku University School of Medicine, Sendai, Japan
12. Department of Obstetrics and Gynecology, Faculty of Medicine, University of Tokyo, Tokyo, Japan
13. Department of Gynecology, Saitama Cancer Center Hospital, Ina, Japan
14. Department of Obstetrics and Gynecology, National Defense Medical College, Tokorozawa, Japan
15. Department of Gynecology, Cancer Institute Hospital, Tokyo, Japan
16. Division of Gynecology and Obstetrics, Graduate School of Medicine, Kyoto University, Kyoto, Japan