title: Distinguishing malignant mesothelioma from pulmonary adenocarcinoma: an immuno-histochemical approach using a panel of monoclonal antibodies.
abstract: A panel of six monoclonal antibodies (MAbs) was employed to evaluate antigen expression in pulmonary adenocarcinomas and mesotheliomas. Monoclonal anti-human milk fat globulin (HMFG-2), anti-carcinoembryonic antigen (NP-2), anti-epithelial membrane antigen (EMA), anti-cytokeratin (PKK-1), anti-tumor-associated antigen 72 (B72.3), and anti-human myelomonocytic antigen (Leu M-1) antibodies were used to localize their respective antigens in formalin-fixed, paraffin-embedded tumors by using the avidin-biotin-complex immunoperoxidase technique. In all, 28 mesotheliomas obtained from Ohio State University Anatomic Pathology files and from a Southwest Oncology Group (SWOG) protocol were compared to 22 pulmonary adenocarcinomas by using this MAb panel. None of the mesotheliomas demonstrated positive staining with MAbs NP-2 (anti-CEA) or Leu M-1. However, 95% (21/22) of adenocarcinomas stained with one of these two antibodies. Although neither of these two MAbs stained all adenocarcinomas, each antibody demonstrated positive immunostaining in more than 90% of the adenocarcinomas studied. Therefore, MABs NP-2 and Leu M-1 are, individually, quite useful for distinguishing mesothelioma from adenocarcinoma. However, in our study, no single MAb could be used to distinguish these two tumor types in every case. MAb B72.3 stained 91% (20/21) adenocarcinomas but also stained 7% (2/28) of mesotheliomas. MAb HMFG-2 reacted positively with 95% of adenocarcinomas, but also stained 39% of the mesotheliomas, usually in a membranous pattern. MAbs EMA and PKK-1 were not found useful in distinguishing mesothelioma from adenocarcinoma. We conclude that MAbs Leu M-1 and NP-2 were both useful in distinguishing mesothelioma from pulmonary adenocarcinoma in that positive staining was demonstrated in adenocarcinomas and not mesotheliomas.
authors.affiliation: Department of Pathology, Ohio State University Hospitals, Columbus.
authors.forename: S E
authors.initials: SE
authors.lastname: Tuttle
authors.forename: J G
authors.initials: JG
authors.lastname: Lucas
authors.forename: D M
authors.initials: DM
authors.lastname: Bucci
authors.forename: J
authors.initials: J
authors.lastname: Schlom
authors.forename: J
authors.initials: J
authors.lastname: Primus
mesh_terms: D000230:Adenocarcinoma / Q000175:diagnosis* / Q000473:pathology; D000911:Antibodies, Monoclonal; D003937:Diagnosis, Differential; D006801:Humans; D007124:Immunoenzyme Techniques; D008175:Lung Neoplasms / Q000175:diagnosis* / Q000473:pathology; D008654:Mesothelioma / Q000175:diagnosis* / Q000473:pathology
chemical_list: D000911:Antibodies, Monoclonal