Painless palpable mass
How would you interpret these lesions?
The first lesion proved to an epidermoid cyst during operation.
The classic sonographic description of an epidermoid cyst is a mass with a target or onion ring appearance. However this is often not the case. The lesion can be inhomogeneous with cystic elements. Histologically the tumor consists of cystic cavities lined by squamous epithelium and contains desquamated keratinized epithelium.
The second and third lesion both proved to be teratomas.
Only one of the teratomas showed some vascularity within the lesion. There is considerable overlap of the sonographic appearances of teratomas and epidermoid cysts of the testis, so in these cases the histological examination is crucial.
The treatment of these lesions is different The epidermoid cyst can be treated by local enucleation, and the teratoma requires radical orchiectomy.
References
Dogra VS, Gottlieb RH, Rubens DJ, Liao L.
Benign intratesticular cystic lesions: US features.
Radiographics. 2001 Oct;21 Spec No:S273-81. Review