1. Department of Pediatric Surgery; Yamanashi Prefectural Central Hospital; Kofu; Japan
2. Department of Orthopedic Surgery; Yamanashi Prefectural Central Hospital; Kofu; Japan
3. Department of Pathology; Yamanashi Prefectural Central Hospital; Kofu; Japan
4. Department of Pediatric Surgery; University of Yamanashi; Chuo; Japan