Testicular adrenal rests
Testicular adrenal rests are a rare cause of a testicular mass.
Can be found in the testis and surrounding tissues in 7.5-15% of newborns and ~1.5% of adults.
Usually adrenal rests are asymptomatic. If these cells are exposed to elevated levels of adrenocorticotropic hormone, they can enlarge to form masses. They can be clinically identified in patients with congenital adrenal hyperplasia and rarely in patients with Cushing syndrome.
Aberrant adrenal rests represent collections of cells that have become trapped within the developing gonad during fetal development. They are usually less than 5 mm.
As with evaluating other testicular pathology, ultrasound is the modality of choice.
The sonographic appearance of adrenal rests is variable, with some series describing predominantly hypoechoic masses and others reporting heterogeneously hyperechoic masses with shadowing. Lesions are typically multiple, bilateral, and eccentrically located.
Treatment and prognosis
It is important to suggest this in the differential diagnosis in the appropriate setting as they are benign lesions and unnecessary orchiectomy can be avoided.
Treatment with glucocorticoid replacement therapy results in stabilization or regression of the masses.