title: Practical Issues for Retroperitoneal Sarcoma.
abstract: BACKGROUND
  Retroperitoneal sarcoma is rare. Using initial specimens on biopsy, a definitive diagnosis of histological subtypes is ideal but not always achievable.
  
  
  METHODS
  A retrospective institutional review was performed for all cases of adult retroperitoneal sarcoma from 1996 to 2015. A review of the literature was also performed related to the distribution of retroperitoneal sarcoma subtypes. A meta-analysis was performed.
  
  
  RESULTS
  Liposarcoma is the most common subtype (45%), followed by leiomyosarcoma (21%), not otherwise specified (8%), and undifferentiated pleomorphic sarcoma (6%) by literature review. Data from Moffitt Cancer Center demonstrate the same general distribution for subtypes of retroperitoneal sarcoma. A pathology-based algorithm for the diagnosis of retroperitoneal sarcoma is illustrated, and common pitfalls in the pathology of retroperitoneal sarcoma are discussed.
  
  
  CONCLUSIONS
  An informative diagnosis of retroperitoneal sarcoma via specimens on biopsy is achievable and meaningful to guide effective therapy. A practical and multidisciplinary algorithm focused on the histopathology is helpful for the management of retroperitoneal sarcoma.
authors.affiliation: Department of Anatomic Pathology, Moffitt Cancer Center, Tampa, FL 33612, USA. Marilyn.Bui@Moffitt.org.
authors.forename: Vicky
authors.initials: V
authors.lastname: Pham
authors.forename: Evita
authors.initials: E
authors.lastname: Henderson-Jackson
authors.forename: Matthew P
authors.initials: MP
authors.lastname: Doepker
authors.forename: Jamie T
authors.initials: JT
authors.lastname: Caracciolo
authors.forename: Ricardo J
authors.initials: RJ
authors.lastname: Gonzalez
authors.forename: Mihaela
authors.initials: M
authors.lastname: Druta
authors.forename: Yi
authors.initials: Y
authors.lastname: Ding
authors.forename: Marilyn M
authors.initials: MM
authors.lastname: Bui
mesh_terms: D005260:Female; D006801:Humans; D008297:Male; D012186:Retroperitoneal Neoplasms / Q000473:pathology / Q000628:therapy*; D012189:Retrospective Studies; D012509:Sarcoma / Q000473:pathology / Q000628:therapy*