title: The value of Wilms tumor susceptibility gene 1 in cytologic preparations as a marker for malignant mesothelioma.
abstract: BACKGROUND
  It has been shown that detection of the Wilms tumor susceptibility gene 1 protein (WT1) has diagnostic utility in the distinction of mesothelioma from adenocarcinoma in tissue sections of pleural tumors. This immunohistochemical study evaluates the effectiveness of WT1 as a marker for malignant mesothelioma in paraffin sections of cell block preparations derived from effusion specimens.
  
  
  METHODS
  The authors evaluated 111 cell blocks for WT1 immunoreactivity, including 14 mesotheliomas and 97 metastatic adenocarcinomas from various sites.
  
  
  RESULTS
  Nuclear reactivity for WT1 was observed in all samples of mesothelioma. However, only 22 of 97 samples (23%) of metastatic adenocarcinoma, nearly all of which were of ovarian origin (91%), exhibited nuclear reactivity for WT1. In 14 other samples (most of pulmonary derivation), WT1 staining restricted to the cytoplasm was observed for some tumor cells and was regarded as nonspecific.
  
  
  CONCLUSIONS
  Based on this staining profile, WT1 represents an effective marker for mesotheliomas in cell block preparations and can aid in its distinction from pulmonary adenocarcinoma. In assessment of effusion specimens with metastatic carcinoma, nuclear reactivity for WT1 is highly suggestive of an ovary primary tumor
authors.affiliation: Department of Pathology, Brigham and Women's Hospital, Boston, Massachusetts 02115, USA.
authors.forename: Jonathan L
authors.initials: JL
authors.lastname: Hecht
authors.forename: Benjamin H
authors.initials: BH
authors.lastname: Lee
authors.forename: Jack L
authors.initials: JL
authors.lastname: Pinkus
authors.forename: Geraldine S
authors.initials: GS
authors.lastname: Pinkus
mesh_terms: D000230:Adenocarcinoma / Q000378:metabolism* / Q000473:pathology / Q000556:secondary; D014408:Biomarkers, Tumor / Q000378:metabolism*; D001706:Biopsy; D001826:Body Fluids / Q000378:metabolism; D003937:Diagnosis, Differential; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D016162:Genes, Wilms Tumor; D006801:Humans; D007124:Immunoenzyme Techniques; D008175:Lung Neoplasms / Q000378:metabolism / Q000473:pathology / Q000556:secondary; D008297:Male; D008654:Mesothelioma / Q000378:metabolism* / Q000473:pathology; D009362:Neoplasm Metastasis; D009369:Neoplasms / Q000378:metabolism*; D010051:Ovarian Neoplasms / Q000378:metabolism / Q000473:pathology; D012680:Sensitivity and Specificity; D025721:WT1 Proteins / Q000378:metabolism*
chemical_list: D014408:Biomarkers, Tumor; D025721:WT1 Proteins