Immunohistochemical characterization of mesothelioma in 6 large felids

Abstract

Mesothelioma has been reported frequently in large felids. These neoplasms present a diagnostic challenge given their highly variable morphology that mimics carcinomas or sarcomas at different locations. Our goal was to characterize mesotheliomas morphologically and immunohistochemically to determine if a panel of antibodies could be used to more accurately support the diagnosis of these neoplasms in large felids. Mesotheliomas from 6 large felids, including 4 clouded leopards, 1 Bengal tiger, and 1 cheetah, were immunohistochemically labeled for vimentin, E-cadherin, pancytokeratin, Wilms tumor 1 (WT1), MUC-1, and calretinin. The mesotheliomas of the 4 clouded leopards and the tiger were of the epithelial subtype; the mesothelioma from the cheetah was biphasic. All 6 mesotheliomas had strong immunohistochemical labeling for vimentin, E-cadherin, and pancytokeratin. All cases had cytoplasmic labeling for WT1, and 2 also had nuclear labeling. The 3 mesotheliomas with distinct papillary fronds were weakly positive for MUC-1. These and one other epithelial mesothelioma were also positive for calretinin. Our study demonstrates that the morphologic and immunohistochemical phenotypes of mesothelioma that have been identified in humans and domestic species can occur in large felids, and a panel of pancytokeratin, vimentin, WT1, and calretinin can be utilized to support the diagnosis of these neoplasms.

Chemosensitivity of three patient-derived primary cultures of canine pericardial mesothelioma by single-agent and combination treatment

“…Because most cancers are typically labeled positively by either pan-cytokeratin or vimentin alone, positive staining with both markers often provides an initial clue for the potential diagnosis of mesothelioma. Thus, dual positivity is usually considered one of the characteristic features of mesothelioma, and both markers are traditionally used in combination for the presumptive identification of mesothelial cells, especially in veterinary medicine, where reliable antibodies are limited (1,2,6,(28)(29)(30)(31). As a few other cancers can show dual positivity, antibodies specific to mesothelial cells, namely WT1 and CK5, were also used in our study.…”

Primary Hepatic Neoplasia in Three Adult Bamboo Sharks (Chiloscyllium Plagiosum and Chiloscyllium Punctatum) in an Aquarium Population

“…Tissue samples (hepatic FFPE blocks) from Cases 1 and 2 were submitted to Michigan State University (Lansing, MI, USA) for immunohistochemistry (IHC) utilizing previously published methodologies. 8 Briefly, IHC for pancytokeratin (Agilent Technologies, M0821, 1:800 dilution; Santa Clara, CA 95051, USA) was performed on serial sections from the tissue block using the BOND-MAX automated staining system, and Bond polymer detection system (Vision BioSystems; Leica, Deer Park, IL 60010, USA) with 3,3 0 -diaminobenzidine as the chromogen. Antigen retrieval was performed utilizing enzymatic antigen retrieval for 20 min.…”