title: Computed tomography manifestations of histologic subtypes of retroperitoneal liposarcoma.
abstract: OBJECTIVE
  Liposarcoma (LPS) is the most common soft tissue sarcoma and accounts for approximately 20% of all mesenchymal malignancies, often occurring in deep soft tissue of retroperitoneal space. Accurate preoperative diagnosis is therefore necessary. We explored whether computed tomography (CT) could be used to differentiate between the various types of retroperitoneal liposarcoma (RPLS).
  
  
  METHODS
  Forty-seven cases of RPLS, diagnosed surgically and histologically, were analyzed retrospectively. CT features were correlated with postoperative pathological appearance.
  
  
  RESULTS
  The study radiologist identified 29, 11, 2, 2 and 3 RPLS as atypical lipomatous tumor/well-differentiated liposarcoma (ALT/WDL), dedifferentiated liposarcoma (DDL), myxoid/round cell liposarcoma (ML/RCL), pleomorphic liposarcoma (PL) and mixed-type liposarcoma. Analysis of CT scans revealed the following typical findings of the different subtypes of RPLS: ALT/WDL was mainly visible as a well-delineated fatty hypodense tumor with uniform density and integrity margin; DDL was marked by the combination of focal nodular density and hypervascularity. ML/RCL, PL and mixed liposarcoma showed malignant biological behaviour and CT findings need further studies.
  
  
  CONCLUSIONS
  CT scanning can reveal important details including internal components, margins and surrounding tissues. Based on CT findings, tumor type can be roughly evaluated and biopsy location and therapeutic scheme guided.
authors.affiliation: Department of Radiation Oncology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China E-mail : sunxinchen2012@163.com.
authors.forename: Jing
authors.initials: J
authors.lastname: Lu
authors.forename: Qin
authors.initials: Q
authors.lastname: Qin
authors.forename: Liang-Liang
authors.initials: LL
authors.lastname: Zhan
authors.forename: Xi
authors.initials: X
authors.lastname: Yang
authors.forename: Qing
authors.initials: Q
authors.lastname: Xu
authors.forename: Jing
authors.initials: J
authors.lastname: Yu
authors.forename: Li-Na
authors.initials: LN
authors.lastname: Dou
authors.forename: Hao
authors.initials: H
authors.lastname: Zhang
authors.forename: Yan
authors.initials: Y
authors.lastname: Yang
authors.forename: Xiao-Chen
authors.initials: XC
authors.lastname: Chen
authors.forename: Yue-Hua
authors.initials: YH
authors.lastname: Yang
authors.forename: Hong-Yan
authors.initials: HY
authors.lastname: Cheng
authors.forename: Xin-Chen
authors.initials: XC
authors.lastname: Sun
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008080:Liposarcoma / Q000145:classification / Q000000981:diagnostic imaging* / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging* / Q000473:pathology*; D009367:Neoplasm Staging; D011379:Prognosis; D012186:Retroperitoneal Neoplasms / Q000145:classification / Q000000981:diagnostic imaging* / Q000473:pathology*; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods*