We would like to thank all the JGOG institutions that participated in this study, and the JGOG Cervical Cancer Committee members for their administrative work for the study. Japanese Gynecologic Oncology Group (JGOG): The following JGOG institutions participated in this study: Saitama Cancer Center, Keio University, Aichi Cancer Center, Kindai University, Kitasato University, University of Tsukuba, Niigata Cancer Center, Kurume University Hospital, Iwate Medical University, The Jikei University, Tohoku University Hospital, Cancer Institute Hospital of the Japanese Foundation for Cancer Research, Juntendo University, St Marianna Medical University Hospital, Tokai University, Kansai Rosai Hospital, Shikoku Cancer Center, Kyoto University, Hokkaido University, Yamagata University, Kyushu Cancer Center, Fujita Medical University, Osaka City University Hospital, University of the Ryukyus, Osaka International Cancer Institute, Shizuoka Cancer Center, Kure Medical Center, National Cancer Center Hospital, Tottori University, Saitama Medical University International Medical Center, Nagoya City University, Niigata University, Jichi Medical University, Oita University, Toho University Ohashi Medical Center, Hokkaido Cancer Center, Kyushu Medical Center, Misawa Municipal Hospital, Hirosaki University, National, Defense Medical College Hospital, Kawasaki Medical University, Kyushu University, Nagasaki University, Rissho Koseikai Hospital, Oji General Hospital, Gifu University, Nagasaki Harbor Medical Center, Nagasaki Medical Center, Okinawa Chubu Hospital, Sagamino Hospital, Kumamoto University, Tokyo Metropolitan Cancer and Infectious Diseases Center Komagome Hospital, Kawasaki Municipal Ida Hospital, Tokyo Medical and Dental University, Chiba University, Aichi Medical University, Dokkyo Medical University Saitama Medical Center, JA Hiroshima General Hospital, Yamanashi Prefectural Central Hospital, Nara Prefectural General Medical Center, Osaka Medical College, Ibaraki Prefectural Central Hospital, Tachikawa Hospital, University of Occupational and Environmental Health Japan, Nara Medical University, Hyogo Cancer Center, Saga University, Tokyo Medical University Ibaraki Medical Center, Yamaguchi University, Tokyo Medical University, Kagoshima City Hospital, Kobe City Medical Center General Hospital, Sapporo Medical University, Kagoshima University, Iizuka Hospital, Miyagi Cancer Center, Japanese Red Cross Society Himeji Hospital, Osaka Rosai Hospital, Japanese Red Cross Ise Hospital, Akita University, Osaka University, Nagoya University, Saiseikai Nagasaki Hospital, The University of Tokyo, Omihachiman Community Medical Center, Kagawa Central Hospital, Kokura Medical Cencer, Yokohama City University Hospital, Kyorin Univerisity, Tottori Municipal Hospital, Seirei Hamamatsu General Hospital, Tomishiro Central Hospital, KKR Sapporo Medical Center, Saiseikai Hita Hospital, Mie Prefectural General Medical Center, Mie University, Tokyo Metropolitan Tama Medical Cencer, NTT East Kanto Hospital, Ehime University, Kanagawa Cancer Center, Chiba Cancer Center, The Jikei University Kashiwa Hospital, Saiseikai Fukuoka General Hospital, The University of Tokushima, Gunma University, Shinshu University, Hyogo Medical University, Kyoto Prefectural University, and Fukushima Medical University.