Testis and epididymis

Author: Turki Al-Hussain, M.D. (see Authors page)

Revised: 5 April 2017, last major update August 2012

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PubMed Search: Cryptorchidism [title] Testis and epididymis

Cite this page: Cryptorchidism. PathologyOutlines.com website. http://pathologyoutlines.com/topic/testiscryptorchidism.html. Accessed April 23rd, 2017.
Definition / General
  • Permanent retention of testis outside scrotum
  • Due to complete or incomplete failure of intra abdominal testes to descend into scrotal sac, occasionally associated with other GU malformations such as hypospadias and with trisomy 13
  • Testicular descent occurs in 2 phases:
    1. Abdomen to pelvic brim: controlled by anti-Müllerian hormone
    2. Pelvic rim to scrotum: androgen dependent, may be mediated by androgen induced release of calcitonin gene related peptide from genitofemoral nerve
Clinical Features
  • Occurs in 3% of newborn boys, 1% of 1 year old boys; more common in premature infants; usually NOT due to endocrine disorder
  • Bilateral in 25% of cases
  • Cryptorchid testis usually (80%) in inguinal canal
  • Cryptorchid testes are prone to trauma, torsion, inguinal hernia (10 - 20% of cases) and sterility
  • Associated with 5 - 50× increased risk of testicular carcinoma, usually seminoma (higher risk if abdominal vs. inguinal location); may have cancer in normal descended testes too; biopsies suggested of both testes to detect intratubular germ cell neoplasia (50% with positive biopsy develop germ cell tumor at 5 years vs. minimal with negative biopsy)
  • Orchiopexy (placement in scrotal sac) should be done before age 2 - 3 to reduce risk of malignancy; deficient spermatogenesis persists in 10 - 60%; better fertility if orchiopexy done at younger age (Hum Pathol 1980;11:666)
Gross Description
  • Small, firm, brown testis
Micro Description
  • Marked hyalinization and thickening of tubular basement membrane, prominent Leydig cells, often hyperplastic Sertoli cells with atrophy of other cells (arrest in germ cell development)
  • Variable intratubular germ cell neoplasia
  • Other testis often has paucity of germ cells
  • May have nodules of hyperplastic Sertoli cells ("Pick's adenomas") or clusters of persistent immature tubules