• Histopathology
• autopsy pathology
• morbid anatomy

Paratesticular mesothelioma is a rare tumour, representing only 0.3–5% of all mesotheliomas; approximately 223 cases have been described to date.1 Morphologically, most paratesticular mesotheliomas are epithelial, or mixed epithelial and sarcomatoid; with papillary, tubulopapillary or solid architectural patterns.2 ,3 Papillary mesotheliomas can be difficult to distinguish from papillary serous carcinoma on morphological grounds alone and usually require immunohistochemical and ultrastructural studies. Mesotheliomas are typically positive for calretinin, CK5/6, D2-40, vimentin and thrombomodulin but negative for BerEp4, LeuM1, CEA and CK20; whereas carcinomas typically show the reverse pattern.1 ,3–5 Rare BerEp4 and LeuM1 positivity is well documented in mesothelioma, although the staining is usually weak …