title: [Histopathological diagnostic concordance in bone and soft tissue sarcomas between two comprehensive cancer centers from eastern and western Europe: a collaborative experience].
abstract: BACKGROUND
  This study aims to assess the degree of concordance of histological diagnosis of bone and soft tissue sarcomas between a Comprehensive Cancer Center (CCC) of Eastern Europe - not specialized in this area of pathology - and an important CCC of Western Europe, which is one of the coordinators of a clinical reference network in sarcoma pathology. The goal is to have an overview of the sarcomatous pathology in a region of Eastern Europe and to discover diagnostic discrepancies between the two centers, while determining their cause.
  
  
  METHODS
  The initial diagnosis was compared with the revised diagnosis on 110 specimens from 88 patients with bone or soft tissue sarcomas from East-European CCC, in a one-year period of time.
  
  
  RESULTS
  Complete diagnostic agreement was observed in 55 cases (62.5%), a partial agreement in 23 cases (26.1%) and a major disagreement in 10 cases (11.4%). Major discrepancies of the histological type was observed in only 3 cases (3.4%): one case of discordance benign/malignant and 2 cases of discordance mesenchymal/non mesenchymal. Minor histological discrepancies - not affecting the management of the patient - were observed in 18 cases (20.4%). A major discordance in grading - potentially changing the management of the patient - was noted in 7 cases (7.9%), and a minor discrepancy in 5 cases (5.7%).
  
  
  CONCLUSIONS
  Some histological types were clearly overdiagnosed, like "adult fibrosarcomas" and "malignant peripheral nerve sheet tumors" (MPNST), mostly converted after the audit into "undifferentiated spindle cell sarcomas" or other types of sarcomas. Some "unclassified" sarcomas and "undifferentiated pleomorphic sarcomas" could be re-classified with the aid of an extensive panel of antibodies. Overall, immunohistochemistry was responsible, but not in exclusivity, for half of the minor discrepancies, and for 2 out of 3 cases of major histological discrepancies. Otherwise, the main cause of discrepancies was the difficulties in the interpretation of the morphology. Molecular biology was decisive in one case. Most grading discrepancies resulted from the appreciation of the mitotic index.
  
  
  CONCLUSIONS
  The profile of the sarcomatous pathology in the northwest region of Romania does not appear to differ significantly from other parts of Europe or the world, but a prospective epidemiological study would be necessary to confirm this assessment. The expansion of immunohistochemical antibody panel, the over-specialization of pathologists and, in the future, the establishment of a national network of referral centers in sarcoma pathology, are required for a high level of histological diagnosis in Eastern Europe. A periodic external audit, continuing this trans-European collaboration between the two centers, would be beneficial for monitoring progress.
authors.affiliation: Institut oncologique Prof. Dr. I. Chiricuta, 34-36, rue Republicii, 400015 Cluj-Napoca, Roumanie.
authors.forename: Oana
authors.initials: O
authors.lastname: Somcutian
authors.affiliation: Institut oncologique Prof. Dr. I. Chiricuta, 34-36, rue Republicii, 400015 Cluj-Napoca, Roumanie. Electronic address: buiga.rares@iocn.ro.
authors.forename: Rares
authors.initials: R
authors.lastname: Buiga
authors.affiliation: Institut oncologique Prof. Dr. I. Chiricuta, 34-36, rue Republicii, 400015 Cluj-Napoca, Roumanie.
authors.forename: Mihaela
authors.initials: M
authors.lastname: Galatir
authors.affiliation: Institut oncologique Prof. Dr. I. Chiricuta, 34-36, rue Republicii, 400015 Cluj-Napoca, Roumanie; Université de médecine et pharmacie Iuliu Haţieganu, 8, rue Babeş, 400012 Cluj-Napoca, Roumanie.
authors.forename: Dan
authors.initials: D
authors.lastname: Tudor Eniu
authors.affiliation: Université de médecine et pharmacie Iuliu Haţieganu, 8, rue Babeş, 400012 Cluj-Napoca, Roumanie.
authors.forename: Claudiu
authors.initials: C
authors.lastname: Rachieru
authors.affiliation: Institut oncologique Prof. Dr. I. Chiricuta, 34-36, rue Republicii, 400015 Cluj-Napoca, Roumanie; Registre régional de cancer du nord-ouest, 34-36, rue Republicii, 400015 Cluj-Napoca, Roumanie.
authors.forename: Daniela
authors.initials: D
authors.lastname: Coza
authors.affiliation: Institut Gustave-Roussy, 114, rue Édouard-Vaillant, 94805 Villejuif cedex, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Terrier
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000032:analysis; D001859:Bone Neoplasms / Q000737:chemistry / Q000175:diagnosis* / Q000453:epidemiology; D002173:Cancer Care Facilities / Q000706:statistics & numerical data*; D002648:Child; D002675:Child, Preschool; D002813:Chondrosarcoma / Q000737:chemistry / Q000175:diagnosis / Q000453:epidemiology; D003937:Diagnosis, Differential; D003951:Diagnostic Errors; D005260:Female; D005602:France / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D008940:Mitotic Index; D060787:Neoplasm Grading; D012516:Osteosarcoma / Q000737:chemistry / Q000175:diagnosis / Q000453:epidemiology; D010337:Pathology Department, Hospital / Q000706:statistics & numerical data*; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012383:Romania / Q000453:epidemiology; D012509:Sarcoma / Q000737:chemistry / Q000175:diagnosis* / Q000453:epidemiology; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor
keywords: Concordance evaluation; Histological review; Osseous sarcoma; Révision histologique; Sarcome de tissus mous; Sarcome osseux; Soft tissue sarcoma; Évaluation de la concordance