title: Asynchronous abdomino-parasacral resection of a giant pelvic lipoma protruding to the left buttock.
abstract: BACKGROUND
  Few reports detail adequate surgical management of giant pelvic tumors that traverse the sciatic foramen.
  
  
  METHODS
  We present a case of a giant retroperitoneal pelvic lipoma that presented with a dumbbell shape on imaging, occupying the entire lesser pelvis and protruding to the gluteus through the sciatic foramen. Surgery was performed for en bloc resection of the tumor.
  
  
  CONCLUSIONS
  A parasacral approach with the patient in the prone position was necessary to dissect the tumor in the buttock, manipulate around the sciatic foramen and preserve collateral blood flow for the gluteal muscle. An abdominal approach was also essential to ligate the internal iliac vessels involved in the tumor. Accordingly changings the position of the patient during the operation were required. Division of the sacrotuberous and sacrospinous ligaments and packing of the soft tumor into a plastic bag were useful to pass the buttock portion through the foramen without the tumor breaking off.
  
  
  CONCLUSIONS
  The asynchronous abdomino-parasacral approach with several turnings of the patient's body and plastic bag packing of the tumor were advantageous to manage en bloc resection of the giant pelvic lipoma presented in this case study.
authors.affiliation: First Department of Surgery, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashiku, Hamamatsu, Shizuoka 431-3192, Japan. Electronic address: msnrsato@hama-med.ac.jp.
authors.forename: Masanori
authors.initials: M
authors.lastname: Sato
authors.affiliation: First Department of Surgery, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashiku, Hamamatsu, Shizuoka 431-3192, Japan.
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Miyaki
authors.affiliation: First Department of Surgery, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashiku, Hamamatsu, Shizuoka 431-3192, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Inamori
authors.affiliation: First Department of Surgery, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashiku, Hamamatsu, Shizuoka 431-3192, Japan.
authors.forename: Junpei
authors.initials: J
authors.lastname: Tochikubo
authors.affiliation: Department of Orthopedic Surgery, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashiku, Hamamatsu, Shizuoka 431-3192, Japan.
authors.forename: Yoji
authors.initials: Y
authors.lastname: Shido
authors.affiliation: First Department of Surgery, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashiku, Hamamatsu, Shizuoka 431-3192, Japan.
authors.forename: Norihiko
authors.initials: N
authors.lastname: Shiiya
authors.affiliation: First Department of Surgery, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashiku, Hamamatsu, Shizuoka 431-3192, Japan.
authors.forename: Hidetoshi
authors.initials: H
authors.lastname: Wada
keywords: Buttock tumor; Giant lipoma; Parasacral approach; Pelvic tumor; Sciatic foramen