title: Appraisal of the comparative utility of immunohistochemistry and electron microscopy in the diagnosis of childhood round cell tumors.
abstract: To provide an objective assessment of the comparative utility of fluorescence- and peroxidase-based immunohistochemistry and electron microscopy, an observer blinded study was conducted under realistic study conditions utilizing a large sampling of poorly differentiated pediatric round cell tumors. Working independently, using a single ancillary technique of particular expertise, each of three investigators attempted to render a specific diagnosis with regard to 50 diagnostically challenging tumors. The results were compared against the subsequent "file diagnosis" established by consensus with all relevant information made available. A grading scheme was applied wherein points were awarded based on the accuracy and confidence of diagnosis. A comparative efficiency rating, expressed as a percentage, was formulated by dividing the number of points awarded each technique by the total number of points theoretically available. Electron microscopy proved superior overall, with an efficiency rating of 89%. Immunoperoxidase and immunofluorescence studies yielded efficiency ratings of 71 and 61%, respectively. Used in combination, the techniques achieved an efficiency rating of 95%. Application of these ancillary techniques resulted in a revision of the provisional diagnosis in 11 of 50 cases, and left only two cases without a firm specific diagnosis.
authors.affiliation: Department of Pathology, Children's Hospital Denver, CO 80218, USA.
authors.forename: G W
authors.initials: GW
authors.lastname: Mierau
authors.forename: P J
authors.initials: PJ
authors.lastname: Berry
authors.forename: R L
authors.initials: RL
authors.lastname: Malott
authors.forename: D A
authors.initials: DA
authors.lastname: Weeks
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D007223:Infant; D008223:Lymphoma / Q000175:diagnosis / Q000276:immunology / Q000648:ultrastructure*; D008297:Male; D008637:Mesenchymoma / Q000175:diagnosis / Q000276:immunology / Q000648:ultrastructure*; D008854:Microscopy, Electron; D009447:Neuroblastoma / Q000175:diagnosis / Q000276:immunology / Q000648:ultrastructure*; D018241:Neuroectodermal Tumors, Primitive, Peripheral / Q000175:diagnosis / Q000276:immunology / Q000648:ultrastructure*; D010340:Pathology, Surgical / Q000379:methods*; D018335:Rhabdoid Tumor / Q000175:diagnosis / Q000276:immunology / Q000648:ultrastructure*; D012208:Rhabdomyosarcoma / Q000175:diagnosis / Q000276:immunology / Q000648:ultrastructure*; D012512:Sarcoma, Ewing / Q000175:diagnosis / Q000276:immunology / Q000648:ultrastructure*; D018228:Sarcoma, Small Cell / Q000175:diagnosis* / Q000276:immunology* / Q000648:ultrastructure; D009396:Wilms Tumor / Q000175:diagnosis / Q000276:immunology / Q000648:ultrastructure*