title: Usefulness of thyroid transcription factor-1 immunohistochemical staining in the differential diagnosis of primary pulmonary tumors of dogs.
abstract: In a previous study, we characterized the reactivity of monoclonal antibody (MoAb) 8G7G3/1 to thyroid transcription factor-1 (TTF-1) in canine thyroid tumors. In this study, we have examined the reactivity of this antibody in 120 canine pulmonary tumors, including 78 primary epithelial tumors. Tissues had been fixed in formalin and routinely processed for histopathology. Nuclear staining for TTF-1 was detected in 64.2% of primary pulmonary epithelial tumors. The most common TTF-1-reactive tumor types were bronchioloalveolar carcinomas and bronchogenic carcinomas. Staining was diffuse, heterogeneous, or patchy. Nonpulmonary, metastatic epithelial tumors, except two of two thyroid carcinomas, did not react with antibody 8G7G3/1. Mesotheliomas and other mesenchymal tumors were also negative for this marker. A reduction or loss of reactivity was apparent in pulmonary epithelial tumors archived in paraffin blocks for 7-8 years. There was slight reduction in the number of positive cells or the intensity of the reaction in control tissues fixed longer than 1 week. On the basis of our limited studies and the human literature, it appears that MoAb 8G7G3/1 to TTF-1 is a highly specific (with the exception of thyroid tumors) and moderately sensitive marker for canine pulmonary epithelial tumors.
authors.affiliation: Animal Disease Diagnostic Laboratory, Purdue University, 406 South University, West Lafayette, IN 47907, USA. ramosja@purdue.edu
authors.forename: J A
authors.initials: JA
authors.lastname: Ramos-Vara
authors.forename: M A
authors.initials: MA
authors.lastname: Miller
authors.forename: G C
authors.initials: GC
authors.lastname: Johnson
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal; D003937:Diagnosis, Differential; D004283:Dog Diseases / Q000175:diagnosis* / Q000473:pathology*; D004285:Dogs; D007150:Immunohistochemistry / Q000379:methods / Q000662:veterinary; D008175:Lung Neoplasms / Q000175:diagnosis / Q000473:pathology / Q000662:veterinary*; D009687:Nuclear Proteins; D012680:Sensitivity and Specificity; D000074482:Thyroid Nuclear Factor 1; D014157:Transcription Factors
chemical_list: D000911:Antibodies, Monoclonal; C000614412:NKX2-1 protein, human; D009687:Nuclear Proteins; D000074482:Thyroid Nuclear Factor 1; D014157:Transcription Factors