title: Evaluation of neoadjuvant therapy and histopathologic response in primary, high-grade retroperitoneal sarcomas using the sarcoma nomogram.
abstract: BACKGROUND
  Patients with primary high-grade retroperitoneal soft tissue sarcomas have a 5-year disease-specific survival (DSS) of <40%. The impact of neoadjuvant therapy on histopathologic response and DSS are unknown.
  
  
  METHODS
  From 1987 to 2007, 55 patients with primary high-grade retroperitoneal sarcoma received neoadjuvant therapy. All patients underwent surgical resection, and response was assessed histopathologically. Patients with >or=95% pathologic necrosis were classified as responders. Clinicopathologic variables were analyzed for association with DSS. Observed DSS was then compared with the Memorial Sloan-Kettering Cancer Center Sarcoma Nomogram predicted DSS.
  
  
  RESULTS
  The median tumor size was 15 cm, and the median follow-up time for survivors was 68 months. The 5-year DSS for all 55 patients was 47% and did not significantly differ from the 37% predicted by the sarcoma nomogram for such patients (P=.44). Fourteen (25%) of the patients had >or=95% pathologic necrosis and were defined as responders; 41 (75%) were nonresponders. The 5-year DSS for responders was 83%. This was significantly better than the 5-year DSS of 34% for nonresponders (P=.002) and the 39% predicted by the sarcoma nomogram for responders (P=.018). The 34% 5-year DSS for nonresponders did not significantly differ from the 35% predicted by the sarcoma nomogram (P=.51).
  
  
  CONCLUSIONS
  Neoadjuvant therapy was not associated with an overall improvement in DSS in patients with primary high-grade retroperitoneal sarcoma compared with the sarcoma nomogram prediction. Histopathologic response to neoadjuvant therapy was associated with a significantly improved DSS compared with nonresponders and with the sarcoma nomogram prediction for such patients.
authors.affiliation: Department of Surgery, Division of Surgical Oncology, University of California at Los Angeles, Los Angeles, California 90095-1782, USA.
authors.forename: Timothy R
authors.initials: TR
authors.lastname: Donahue
authors.forename: Michael W
authors.initials: MW
authors.lastname: Kattan
authors.forename: Scott D
authors.initials: SD
authors.lastname: Nelson
authors.forename: William D
authors.initials: WD
authors.lastname: Tap
authors.forename: Frederick R
authors.initials: FR
authors.lastname: Eilber
authors.forename: Fritz C
authors.initials: FC
authors.lastname: Eilber
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D017024:Chemotherapy, Adjuvant; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D049451:Nomograms; D018714:Radiotherapy, Adjuvant; D012186:Retroperitoneal Neoplasms / Q000401:mortality / Q000473:pathology / Q000601:surgery / Q000628:therapy*; D012509:Sarcoma / Q000401:mortality / Q000473:pathology / Q000601:surgery / Q000628:therapy*; D016019:Survival Analysis