Benign intratesticular cystic lesions: US features.

Benign intratesticular lesions are rare, but recognition is important to avoid unnecessary surgical intervention. The ultrasonographic (US) features that help differentiate benign from malignant intratesticular lesions are emphasized by the authors. Benign lesions include intratesticular simple cysts, tubular ectasia, epidermoid cyst, tunica albuginea cyst, intratesticular varicocele, abscess, and hemorrhage (infarction). US features of cystic malignant neoplasms that help in differentiation of them from benign cystic lesions are also presented. The US appearance of epidermoid cysts varies with the maturation, compactness, and quantity of keratin present. Of the cystic malignant testicular tumors, which can occur anywhere in testicular parenchyma, teratomas are the most frequent to manifest as cystic masses. An abnormal rind of parenchyma with increased echogenicity usually surrounds these lesions. An intratesticular spermatocele communicates with the seminiferous tubules, whereas simple ectasia of the rete testis does not do so directly. These cysts contain spermatozoa and can be septate. The US findings of intratesticular varicocele are similar to those of extratesticular varicocele and include multiple anechoic, serpiginous, tubular structures of varying sizes. Improvements in gray-scale and Doppler US technology allow subtle distinctions between benign and malignant testicular lesions that were not possible a decade earlier.