Paraneoplastic nephritic syndrome and concurrent solitary mediastinal lymph node metastasis from mesothelioma of testis diagnosed by endobronchial ultrasound: Unusual manifestations of an extremely rare tumor.

Malignant mesothelioma is most commonly found in the pleura, peritoneum and pericardium, whereas mesothelioma of the tunica vaginalis testis is exceedingly rare. The usual sites of metastasis are inguinal nodes, retroperitoneal lymph nodes and lung. Herein, we describe a patient with mesothelioma of testis, who presented with paraneoplastic glomerulopathy and asymptomatic solitary mediastinal lymphadenopathy on serial computed tomography imaging after radical orchiectomy. A diagnosis of metastatic lymph nodal disease was set by using convex-probe endobronchial ultrasound (EBUS) with transbronchial needle aspiration. We also briefly discuss clinical, etiological, pathological and therapeutical aspects of the disease, and highlight the paramount importance of real-time EBUS as the preferred method in the diagnostic approach of mediastinal lesions.