Testis & paratestis



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PubMed Search: Cryptorchidism [TI] testis and epididymis

Christopher Dall, M.D.
Debra L. Zynger, M.D.
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Cite this page: Dall C, Zynger DL. Cryptorchidism. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/testiscryptorchidism.html. Accessed June 9th, 2023.
Definition / general
  • Absence of one or both testes in the scrotum
  • Most common congenital abnormality of the genitourinary tract (Transl Pediatr 2016;5:233)
  • Associated with infertility and subfertility, testicular germ cell tumor, testicular torsion and inguinal hernia
Essential features
  • Absence of one or both testes in the scrotum most commonly due to failure of descent into the scrotum during fetal development
  • Increased risk of reduced fertility and testicular germ cell tumor
  • Cryptorchidism: absence of one or both testes in the scrotum
  • Anorchia or vanishing testis syndrome: absence of one or both testes
  • Orchiopexy or orchidopexy: procedure that tethers the testicle into the scrotum
  • Ectopic testis: testis is situated away from normal path of descent; differs from undescended testicle
ICD coding
  • ICD-10:
    • Q53.1 - undescended testicle, unilateral
    • Q53.2 - undescended testicle, bilateral
    • Q53.9 - undescended testicle, unspecified
  • Undescended testicle may be located in the abdomen or inguinoscrotal region
  • Testicular descent from initial position on abdominal wall is divided into 2 stages with abnormalities of migration thought to be associated with undescended testicle (Endocr Rev 2008;29:560)
    • Transabdominal descent: the gubernaculum, a caudal ligament connecting the testicle to the internal ring, holds testicle near internal ring as abdominal cavity develops; insulin-like factor 3 (INSL3) and anti-Müllerian hormone dependent
    • Inguinoscrotal descent: the gubernaculum shortens, pulling testicle through inguinal canal to position within scrotum; androgen dependent
  • May be a component of testicular dysgenesis syndrome, which includes increased levels of testicular malignancy, poor semen quality and hypospadias
Clinical features
  • 80% of undescended testicles palpated within inguinal canal or high scrotal area
  • 20% of undescended testicles not palpated
  • Associated with increased risk of testicular germ cell tumor
    • Increasing risk of malignancy with delayed treatment (J Urol 2009;181:452)
    • Relative risk of malignancy is 2 - 8x; higher risks associated with delayed repair, bilateral cryptorchidism, additional endocrinopathies, abnormal karyotype and intra-abdominal testes
    • Seminoma is most common malignancy
  • In cases of bilateral undescended testicles, hormonal studies (LH, FSH, Müllerian inhibiting substance [MIS] and testosterone) may support diagnosis of gonadal dysgenesis with abnormal hCG stimulation test (Am Fam Physician 2000;62:2037)
Radiology description
Prognostic factors
  • Delayed repair reduces fertility, which is worse with bilateral cryptorchidism
  • Relative risk for testicular germ cell tumor is 2.2x with prepubertal repair versus 5.4x with postpubertal repair (N Engl J Med 2007;356:1835)
Case reports
Clinical images

Images hosted on other servers:

Intra-abdominal mass

Abdominal testis

Mass with right gonadal vein

Scrotum with cryptorchidism

Abdominal wall ectopic testis

Gross description
  • Smaller and atrophic compared to descended testis
Gross images

Contributed by Debra L. Zynger, M.D.

Cryptorchid testicle

Microscopic (histologic) description
  • Histopathologic differences become much more pronounced after 2 years of life and are increased with delayed orchiopexy (J Urol 2009;182:704)
  • Peritubular fibrosis
  • Seminiferous tubule atrophy
  • Decreased / absent spermatogenesis
  • Sertoli cells may demonstrate granular cell change with eosinophilic granular cytoplasmic lysosomes
  • Sertoli cell only seminiferous tubules: tubules with only bland, monotonous pale cells with granular cytoplasm attached to the basement membrane; absent germ cells and no spermatogenesis
  • Sertoli cell nodule: nodules composed of immature elongated Sertoli cells (Pick adenoma) may be present; can have central microliths
  • Increased microliths within seminiferous tubules
  • Retained Leydig cells give appearance of hyperplasia
  • Evaluate for germ cell neoplasia in situ (GCNIS): large, pleomorphic, basally located cells within the seminiferous tubules may be present; use immunostains for confirmation
Microscopic (histologic) images

Contributed by Debra L. Zynger, M.D.

Sertoli cell only tubules

Absent spermatogenesis

Peritubular fibrosis

Sertoli cell nodule

Retained Leydig cells

Granular cell change within Sertoli cells


Cytology description
  • Not used to evaluate a cryptorchid testis
Positive stains
Sample pathology report
  • Ectopic testis, removal:
    • Seminiferous tubules with Sertoli only tubules, peritubular fibrosis, no spermatogenesis and microliths consistent with cryptorchid testis
Differential diagnosis
  • Germ cell neoplasia in situ (GCNIS):
    • Atypical cells with large nuclei located next to the basement membrane of the seminiferous tubules
    • Cytoplasmic clearing around nuclei
    • Heterogeneity of cells within seminiferous tubules
    • Positive for CD117, PLAP, D2-40, OCT 3/4 (but can be falsely positive in boys < 2 years old with cryptorchidism)
Board review style question #1
A 24 year old man with a history of untreated cryptorchidism presents with a painful abdominal mass. Pathology is most likely to be consistent with which of the following?

  1. Dermoid cyst
  2. Germ cell neoplasia in situ
  3. Mixed germ cell tumor
  4. Seminoma
  5. Sertoli cell tumor
Board review style answer #1
D. Seminoma is the most common malignancy in the setting of cryptorchidism.

Comment Here

Reference: Cryptorchidism
Board review style question #2

What histological changes are most likely to be observed in a nonneoplastic cryptorchid testis?

  1. Atrophic seminiferous tubules, peritubular fibrosis and nodules of cells containing dark nucleoli and eosinophilic granular cytoplasm
  2. Bland appearing cysts lined with cuboidal epithelium and ciliated cells
  3. Cysts lined by squamous cells filled with keratin
  4. Glycogen rich cells with large, irregular nuclei arranged in sheets
  5. Rod-like cytoplasmic inclusions with a diffuse growth pattern and rare mitotic cells
Board review style answer #2
A. Atrophic seminiferous tubules, peritubular fibrosis and nodules of cells containing dark nucleoli and eosinophilic granular cytoplasm are findings consistent with an undescended testicle. B is incorrect because these might be the findings associated with benign glands, such as those seen in endometriosis or endosalpingiosis. C is incorrect because this histology may be associated with teratoma. D is incorrect because these might be the findings of a seminoma, which are more common in undescended testicles. E is incorrect because Leydig cell tumors often contain Reinke crystals, described in this answer choice.

Comment Here

Reference: Cryptorchidism
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