Authors: Macfarlane, Michael T.
Title: Urology, 4th Edition
Copyright 2006 Lippincott Williams & Wilkins
> Table of Contents > Part One - Chief Presentations > Chapter 11 - Empty Scrotum
Cryptorchidism is a common disorder in pediatric urology. It has been observed to occur in 3% of term infants and 30% of premature infants; however, 75% and 90% of these undescended testes, respectively, will have spontaneously descended by age 1 year, leaving a true incidence of close to 1% (0.8%) of the male population. Ten percent of cases are bilateral, 3% of which will have one or both testes absent. The etiology is unclear, and although many genetically inherited diseases have a high association with cryptorchidism, most cases of the undescended testis are isolated with no evidence of a genetic component.
A 20-fold increased risk of developing a testicular malignancy has been noted with undescended testes. Ten percent of testicular cancers arise in an undescended testis, 60% of which will be seminomas. The intraabdominal testis is four times more likely to undergo malignant degeneration than is an inguinal testis.
Fertility is impaired. Only 30% of patients with bilateral cryptorchidism will be fertile. Spermatogenic damage appears to increase with higher position and longer periods of extrascrotal habitation.
A high incidence of associated inguinal hernias (25%) occurs because of the patent processus vaginalis.
An increased susceptibility to torsion exists, especially in the postpubertal period.
Intraabdominal (10%) testis is located proximal to the internal inguinal ring within the abdominal cavity.
Inguinal canal testis is located between internal and external inguinal rings.
Ectopic testis is located distal to the internal ring but outside its normal path of descent. Most are found in the superficial inguinal pouch or in the perineum, femoral canal, suprapubic area, and, rarely, in the contralateral scrotal compartment.
Absent testes (4%) 20% of nonpalpable testes are absent.
Retractile testis testis is not truly undescended. Its extrascrotal location is secondary to hyperactive contraction of the cremasteric muscle. It is commonly found in the prescrotal or low inguinal area and with gentle manipulation can be placed in the scrotum without tension.
Carefully palpate both scrotal compartments, the inguinal canals, perineum, suprapubic area, and femoral canal. A palpable testis will be inguinal, ectopic, or retractile. If the testis can be easily placed within the scrotum without tension, it is retractile. Note that the cremasteric reflex is most active between ages 2 and 7 years, making this diagnosis difficult. A nonretractile palpable testis is either inguinal or ectopic.
A nonpalpable testis is either intraabdominal, ectopic, inguinal, or absent. If both testes are impalpable, then measure serum testosterone response to human chorionic gonadotropin (hCG) stimulation (hCG 2,000 IU qd 3 days) and basal follicle-stimulating (FSH) and luteinizing hormone (LH) levels. A negative testosterone response to hCG and elevated basal FSH and LH levels are reliable evidence of anorchism (bilateral testicular absence). Bilateral or unilateral nonpalpable nondescensus can be further investigated by ultrasound, computed tomography, laparoscopy, and surgical exploration. Most testes will be found at surgery close to the internal inguinal ring.
Why Treat Undescended Testis?
To decrease the potential for malignant degeneration and to make the testis easier to palpate
To improve prospects for fertility
To repair inguinal hernias
To decrease risk of torsion
To avoid potential psychological complications
Therapy should be undertaken between ages 6 and 18 months. This will allow adequate time for spontaneous descent to occur and should minimize the potential complications of infertility and malignant degeneration. Retractile testes need no further therapy; however, periodic reexamination to confirm the diagnosis would be prudent. The truly undescended testes can be treated with either hormonal or surgical therapy or both.
Exogenous gonadotropin-releasing hormone or hCG has been reported to be successful in bringing down the testis in up to 70% and 50% of patients, respectively. Hormonal therapy is contraindicated with ectopic testes, in the setting of a hernia, and after prior orchiopexy or herniorrhaphy.
Several different procedures for orchiopexy are effective, all based on the principles of adequate mobilization and fixation and repair of the associated hernia. Exploration for a nonpalpable testis is most commonly done with diagnostic laparoscopy. Orchiectomy should be performed if the testis cannot be placed in an easily palpable position and perhaps with all intraabdominal testes.