Observed in monorchidism, cryptorchidism, and after testicular injury.
Hypertrophy occurs prior to or during puberty, but thereafter the hypertrophic testis returns to normal or remains only slightly enlarged.
Results from alteration in the hypophyseal hormonal feedback, which increases secretion of FSH and enlargement of the remaining testis.
Idiopathic Benign Macroorchidism
Most likely a result of altered hormonal receptivity in the testicular parenchyma.
Generally seen in pubertal and prepubertal patients.
Increased mass is often due to increased length of the seminiferous tubules, but other minor changes may occur (increased tubular diameter, Leydig cell hyperplasia, etc.).