title: Retroperitoneal solitary fibrous tumor of the pelvis with pollakiuria: a case report.
abstract: BACKGROUND
  Solitary fibrous tumor (SFT) is rare soft tissue tumor, and it occurs most commonly in the pleura. Retroperitoneal SFT is generally found by palpable mass or abdominal distention. Here we report a case of SFT presenting pollakiuria.
  
  
  METHODS
  A 64-year-old man was referred to our hospital for pollakiuria. Contrasted-enhanced computed tomography revealed a heterogeneously enhanced pelvic tumor of approximately 10 × 8 × 7 cm. Invasion of the surrounding organs, distal metastasis, and lymph node swelling were absent. Therefore, surgical resection was performed. The resected specimen was a 13 × 8 × 5.5-cm encapsulated elastic hard tumor weighing 420 g. Histologically, the tumor consisted of oval or spindle cells growing in a random manner in a collagenous matrix. Immunohistochemically, the specimen was positive for CD34, bcl-2, as well as vimentin and negative for c-kit. On the basis of these findings, a retroperitoneal solitary fibrous tumor (SFT) of the pelvis was diagnosed.
  
  
  CONCLUSIONS
  Surgery is the primary treatment for SFT, and pathologically negative margins are important for good prognosis.
authors.affiliation: Department of Surgery and Department of Pathology, Ehime Rosai Hospital, Minamikomatsubara-cho 13-27, Niihama, Ehime, 792-8550, Japan. ttsushimi@yahoo.co.jp
authors.forename: Takaaki
authors.initials: T
authors.lastname: Tsushimi
authors.forename: Takaharu
authors.initials: T
authors.lastname: Yagi
authors.forename: Naobumi
authors.initials: N
authors.lastname: Tomozawa
authors.forename: Hiromi
authors.initials: H
authors.lastname: Ohnishi
mesh_terms: D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D010386:Pelvic Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D012187:Retroperitoneal Space / Q000473:pathology*; D054364:Solitary Fibrous Tumors / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D014057:Tomography, X-Ray Computed