title: Clinicopathologic prognostic factors of pure myxoid liposarcoma of the extremities and trunk wall.
abstract: BACKGROUND
  Myxoid liposarcoma is generally considered a low grade tumor but the presence of areas of round cells exceeding 5% is reportedly associated with a worse prognosis. Whether "pure" tumors without round cells are low grade has not been confirmed. While radiotherapy has been used for patients' myxoid liposarcoma it is unclear whether it reduces local recurrences.
  
  
  OBJECTIVE
  We therefore determined the survival, roles of radiotherapy for local control, and prognostic factors of pure myxoid liposarcoma of the extremities and trunk wall.
  
  
  METHODS
  We retrospectively reviewed 53 patients histologically diagnosed with pure myxoid liposarcoma arising in extremities and the trunk wall. Nine patients of the 53 received radiotherapy for primary tumors. Clinical features and prognosis was determined, and various factors were analyzed as to their usefulness as prognostic factors (age, gender, location, size, depth, surgical margin, and adjuvant radiotherapy). The minimum followup was 12 months (mean, 60 months; range, 12-226 months).
  
  
  RESULTS
  Seven (13%) and 6 (11%) patients developed a local recurrence and distant metastasis, respectively. The 5- and 10-year disease-specific and disease-free survival rates were 90% and 83% and 77% and 77%, respectively. Radiotherapy had no impact on either overall or disease free survival. Age (older than 60 years) independently predicted worse overall and disease-free survival.
  
  
  CONCLUSIONS
  In pure myxoid liposarcoma located in the extremities and trunk wall, relatively few patients developed distant metastasis suggesting the tumor is generally low grade. Local control could be achieved with wide surgical margins without radiotherapy. Age was associated with lower survival but size and depth were not. Myxoid liposarcoma in older patients requires special consideration for treatment and followup.
authors.affiliation: Department of Orthopaedic Surgery, Nagoya University Graduate School and School of Medicine, 65 Tsurumai, Showa-ku, Nagoya, Aichi, 466-8550, Japan. ynishida@med.nagoya-u.ac.jp
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Nishida
authors.forename: Satoshi
authors.initials: S
authors.lastname: Tsukushi
authors.forename: Hiroatsu
authors.initials: H
authors.lastname: Nakashima
authors.forename: Naoki
authors.initials: N
authors.lastname: Ishiguro
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D018572:Disease-Free Survival; D005121:Extremities; D005260:Female; D006801:Humans; D007564:Japan; D053208:Kaplan-Meier Estimate; D018208:Liposarcoma, Myxoid / Q000401:mortality / Q000556:secondary / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000401:mortality / Q000517:prevention & control; D019637:Orthopedic Procedures; D016016:Proportional Hazards Models; D018714:Radiotherapy, Adjuvant; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D012983:Soft Tissue Neoplasms / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D015996:Survival Rate; D013997:Time Factors; D016896:Treatment Outcome; D055815:Young Adult