Tubular ectasia of the rete testis (TERT). Differential diagnosis of cystic testicular disorders.

The ultrasound scan plays an essential role in the urological-andrological diagnosis. High-resolution transducers (8-15 MHz) make it possible to prove increasingly small changes. The assessment of cystic masses in the testis can also be difficult for experienced doctors. However, a precise diagnosis is crucial for the patient to avoid further invasive diagnostics and therapy. The differential diagnosis of benign intra-testicular cystic lesions include the tubular ectasia of the rete testis (TERT), the cystic dysplasia, epidermoid cysts, dermoid cysts, simple testicular cysts and cysts of the tunica albuginea. Malign testicular tumours with cystic changes are particularly the mature teratoma, carcinomas of the epididymis and metastasis. The following overview shows different sonographic images and interpretations with a particular focus on TERT.