Testicular masses associated with congenital adrenal hyperplasia: MRI findings

[Testicular adrenal rests: the role of imaging]

Testicular adrenal rests are encountered in ACTH hypersecretion syndromes, most often in congenital adrenal hyperplasia attributable to a deficit in 21-hydroxylase. They are discovered clinically or on systematic sonography, generally in the young adult. On sonography, they appear as confluent hypoechogenic masses, often bilateral, that have developed in the region of the testicular hilum. At a late stage, they take on a highly suggestive attenuating aspect. In color Doppler, they have a regular vascular architecture. They generally regress or stabilize with replacement glucocorticosteroid treatment. They can sometimes progress, which then poses the problem of the type of lesion. Biopsy or spermatic vein samples are not reliable. MRI contributes very little more than sonography. Diagnosis comes with follow-up or, as a last resort, orchidectomy.

From the archives of the AFIP: tumors and tumorlike lesions of the testis: radiologic-pathologic correlation

Testicular carcinoma represents only 1% of all neoplasms in men, but it is the most common malignancy in the 15-34-year-old age group. Germ cell tumors constitute 95% of all testicular tumors. Germ cell tumors are a varied group of neoplasms whose imaging features reflect their underlying histologic characteristics. Seminomas are generally well-defined homogeneous lesions, whereas the nonseminomatous tumors (embryonal carcinoma, yolk sac tumor, choriocarcinoma, teratoma, and mixed germ cell tumor) have a much more varied appearance. Germ cell tumors follow a predictable pattern of spread via the lymphatic drainage to the retroperitoneal nodes. Choriocarcinoma, which has a proclivity for early hematogenous spread, is a notable exception. Testicular tumors may also arise from the sex cords (Sertoli cells) and stroma (Leydig cells). Although 90% of these tumors are benign, there are no reliable imaging criteria to differentiate them from malignant masses. Some benign testicular masses can be recognized, obviating an unwarranted orchiectomy. A dilated rete testis is a normal variant and appears as a series of small tubules near the mediastinum testis. Other benign lesions that can be suspected on the basis of imaging findings and history include intratesticular cysts, epidermoid cysts, congenital adrenal hyperplasia, and sarcoidosis.