title: Malignant solitary fibrous tumor originating from the peritoneum and review of the literature.
abstract: BACKGROUND
  Solitary fibrous tumor (SFT) is a rare neoplasm frequently involving the pleura. Benign and malignant forms of the tumor occur, the benign variant being three to four times more common than the malignant.
  
  
  METHODS
  We present herein a rare case of large malignant solitary fibrous tumor (SFT) originating from the peritoneum. An abdominal computed tomography scan revealed a well-defined solid tumor with mixed density. An abdominal ultrasonography (US) revealed a well-circumscribed solid tumor containing a partially cystic lesion. T1-weighted abdominal magnetic resonance imaging demonstrated a hypo- to isointensity, which was a hypo- to hyperintensity on T2-weighted images. Liposarcoma originating from the retroperitoneum was suggested, and the patient underwent a complete resection of the tumor as well as the left kidney because tumor invasion of the upper left kidney was suspected. Immunohistochemically, the spindle-shaped cells were positive for CD34, and the diagnosis was SFT originating from the peritoneum. At the 14-month follow-up evaluation, no recurrence or metastasis was detected.
  
  
  CONCLUSIONS
  This case gave us some difficulty, and the correct diagnosis of the peritoneal mass was valuable. To diagnose the malignant potential of this type of tumor accurately may have value to direct the appropriate therapeutic operations after surgery and postoperative progress observation.
authors.affiliation: Department of Gastroenterological Surgery, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan.
authors.forename: Moritsugu
authors.initials: M
authors.lastname: Tanaka
authors.forename: Hirozumi
authors.initials: H
authors.lastname: Sawai
authors.forename: Yuji
authors.initials: Y
authors.lastname: Okada
authors.forename: Minoru
authors.initials: M
authors.lastname: Yamamoto
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Funahashi
authors.forename: Tetsushi
authors.initials: T
authors.lastname: Hayakawa
authors.forename: Hiromitsu
authors.initials: H
authors.lastname: Takeyama
authors.forename: Tadao
authors.initials: T
authors.lastname: Manabe
mesh_terms: D000328:Adult; D018952:Antigens, CD34 / Q000378:metabolism; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007150:Immunohistochemistry; D018218:Neoplasms, Fibrous Tissue / Q000737:chemistry / Q000175:diagnosis* / Q000378:metabolism / Q000473:pathology* / Q000601:surgery; D010534:Peritoneal Neoplasms / Q000737:chemistry / Q000175:diagnosis* / Q000378:metabolism / Q000473:pathology* / Q000601:surgery; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
chemical_list: D018952:Antigens, CD34