title: Pathology reporting of neuroendocrine tumors: application of the Delphic consensus process to the development of a minimum pathology data set.
abstract: Epithelial neuroendocrine tumors (NETs) have been the subject of much debate regarding their optimal classification. Although multiple systems of nomenclature, grading, and staging have been proposed, none has achieved universal acceptance. To help define the underlying common features of these classification systems and to identify the minimal pathology data that should be reported to ensure consistent clinical management and reproducibility of data from therapeutic trials, a multidisciplinary team of physicians interested in NETs was assembled. At a group meeting, the participants discussed a series of "yes" or "no" questions related to the pathology of NETs and the minimal data to be included in the reports. After discussion, anonymous votes were taken, using the Delphic principle that 80% agreement on a vote of either yes or no would define a consensus. Questions that failed to achieve a consensus were rephrased once or twice and discussed, and additional votes were taken. Of 108 questions, 91 were answerable either yes or no by more than 80% of the participants. There was agreement about the importance of proliferation rate for tumor grading, the landmarks to use for staging, the prognostic factors assessable by routine histology that should be reported, the potential for tumors to progress biologically with metastasis, and the current status of advanced immunohistochemical and molecular testing for treatment-related biomarkers. The lack of utility of a variety of immunohistochemical stains and pathologic findings was also agreed upon. A consensus could not be reached for the remaining 17 questions, which included both minor points related to extent of disease assessment and some major areas such as terminology, routine immunohistochemical staining for general neuroendocrine markers, use of Ki67 staining to assess proliferation, and the relationship of tumor grade to degree of differentiation. On the basis of the results of the Delphic voting, a minimum pathology data set was developed. Although there remains disagreement among experts about the specific classification system that should be used, there is agreement about the fundamental pathology data that should be reported. Examination of the areas of disagreement reveals significant opportunities for collaborative study to resolve unanswered questions.
authors.affiliation: Department of Pathology, Memorial Sloan-Kettering Cancer Center, New York, NY 10065, USA. klimstrd@mskcc.org
authors.forename: David S
authors.initials: DS
authors.lastname: Klimstra
authors.forename: Irvin R
authors.initials: IR
authors.lastname: Modlin
authors.forename: N Volkan
authors.initials: NV
authors.lastname: Adsay
authors.forename: Runjan
authors.initials: R
authors.lastname: Chetty
authors.forename: Vikram
authors.initials: V
authors.lastname: Deshpande
authors.forename: Mithat
authors.initials: M
authors.lastname: Gönen
authors.forename: Robert T
authors.initials: RT
authors.lastname: Jensen
authors.forename: Mark
authors.initials: M
authors.lastname: Kidd
authors.forename: Matthew H
authors.initials: MH
authors.lastname: Kulke
authors.forename: Ricardo V
authors.initials: RV
authors.lastname: Lloyd
authors.forename: Cesar
authors.initials: C
authors.lastname: Moran
authors.forename: Steven F
authors.initials: SF
authors.lastname: Moss
authors.forename: Kjell
authors.initials: K
authors.lastname: Oberg
authors.forename: Dermot
authors.initials: D
authors.lastname: O'Toole
authors.forename: Guido
authors.initials: G
authors.lastname: Rindi
authors.forename: Marie E
authors.initials: ME
authors.lastname: Robert
authors.forename: Saul
authors.initials: S
authors.lastname: Suster
authors.forename: Laura H
authors.initials: LH
authors.lastname: Tang
authors.forename: Chin-Yuan
authors.initials: CY
authors.lastname: Tzen
authors.forename: Mary Kay
authors.initials: MK
authors.lastname: Washington
authors.forename: Betram
authors.initials: B
authors.lastname: Wiedenmann
authors.forename: James
authors.initials: J
authors.lastname: Yao
mesh_terms: D014408:Biomarkers, Tumor / Q000032:analysis; D002454:Cell Differentiation; D049109:Cell Proliferation; D057189:Checklist / Q000592:standards*; D003245:Consensus Statements as Topic; D003697:Delphi Technique; D005821:Genetic Techniques / Q000592:standards; D006801:Humans; D007150:Immunohistochemistry / Q000592:standards; D009367:Neoplasm Staging / Q000592:standards*; D018358:Neuroendocrine Tumors / Q000737:chemistry / Q000145:classification / Q000473:pathology* / Q000556:secondary; D017410:Practice Guidelines as Topic; D011237:Predictive Value of Tests; D011379:Prognosis; D015203:Reproducibility of Results; D009626:Terminology as Topic
chemical_list: D014408:Biomarkers, Tumor