Mesothelial Lesions of the Testis: A Review. (PubMed, Adv Anat Pathol)
Architecturally more complex forms within this spectrum exist and have been labelled as having "uncertain malignant potential." Malignant mesothelioma of the tunica vaginalis is an uncommon but aggressive tumor that may show loss of BAP1 or MTAP immunostaining, supporting a distinct molecular pathogenesis. This review summarizes the clinicopathologic, immunohistochemically, and molecular features of mesothelial lesions of the paratestis, emphasizing their morphologic overlap, diagnostic pitfalls, and evolving framework for classification.