title: Progressive approach to the cytologic diagnosis of retroperitoneal spindle cell tumors.
abstract: OBJECTIVE
  To assess the utility of fine needle aspiration biopsy (FNAB) in retroperitoneal spindle cell tumors with difficult tumor typing.
  
  
  METHODS
  Thirty-six cases of spindle cell tumors of the retroperitoneum were studied. Cytological diagnoses were set progressively: first exclusively by morphologic criteria on routinely stained slides, and then with the aid of immunocytochemistry (ICC), electron microscopy (EM) and clinical data.
  
  
  RESULTS
  The morphologic diagnosis of benignity or malignancy was first made in double blind fashion by two researchers; it permitted an exact diagnosis in 31 cases (86%) by one examiner and 27 cases (75%) by the second. Using a progressive approach, benignity or malignancy was definitively determined in 35 cases (97%). As far as cytologic tumor typing is concerned, first it proved to be possible in 27 cases (75%) and then in 30 cases (83%) with the progressive approach.
  
  
  CONCLUSIONS
  FNAB proved to be a useful tool in the diagnosis of retroperitoneal spindle cell tumors. A progressive approach to cytopathologic diagnosis, correlating morphology with ICC and EM results and matching them with clinical data, permitted a better differential diagnosis between benign and malignant spindle cell tumors and increased the possibility of correct tumor typing.
authors.affiliation: Department of Cytopathology, Regional Hospital of Ancona, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Ferretti
authors.forename: P M
authors.initials: PM
authors.lastname: Gusella
authors.forename: A M
authors.initials: AM
authors.lastname: Mancini
authors.forename: L
authors.initials: L
authors.lastname: Mancini
authors.forename: A
authors.initials: A
authors.lastname: Vecchi
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001707:Biopsy, Needle; D002648:Child; D003937:Diagnosis, Differential; D004311:Double-Blind Method; D005260:Female; D018219:Histiocytoma, Benign Fibrous / Q000175:diagnosis / Q000473:pathology / Q000648:ultrastructure; D006801:Humans; D007150:Immunohistochemistry; D007890:Leiomyosarcoma / Q000175:diagnosis* / Q000473:pathology / Q000648:ultrastructure; D008080:Liposarcoma / Q000175:diagnosis / Q000473:pathology / Q000648:ultrastructure; D008297:Male; D008854:Microscopy, Electron; D008875:Middle Aged; D009442:Neurilemmoma / Q000175:diagnosis / Q000473:pathology / Q000648:ultrastructure; D012186:Retroperitoneal Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000648:ultrastructure; D018235:Smooth Muscle Tumor / Q000175:diagnosis / Q000473:pathology / Q000648:ultrastructure; D012983:Soft Tissue Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000648:ultrastructure