Testis

From Libre Pathology
Revision as of 15:34, 18 May 2010 by Michael (talk | contribs) (→‎IHC: +ref, correct. CD30)
Jump to navigation Jump to search

The Testes are important for survival of the species. Tumours occasionally arise in 'em. They generally are not biopsied. If they are biopsied, it is usually for fertility -- to understand whether they are really azoospermic.

Normal

Seminiferous tubules

  • Sertoli cells (aka sustentacular cell aka nurse cell).
    • Large cells with oval nucleus.
  • Primary spermatocyte.
    • Small cells with dark nucleus on basement membrane.
  • Secondary spermatocyte.
    • Rarely seen on light microscopy.
  • Spermatids.
    • Round small.
    • Usually close to the centre of the lumen.
  • Spermatozoa.
    • You don't see the tail on light microscopy.

Interstitium

  • Leydig cell.
    • Large eosinophilic cell.

Diagnoses

  • Benign.
    • Spermatid present/not present.
  • Infertility - azoospermic.
    • No sperm present.
  • Germ cell tumours (GCTs).
    • Intratubular germ cell neoplasia.
    • Seminoma.
    • Spermatocytic seminoma.
    • Yolk sac tumour (endodermal sinus tumour).
    • Embryonal carcinoma.
    • Choriocarcinoma.
    • Teratoma.
    • Mixed GCT - 60% of GCTs are mixed.
      • Common combinations:
        1. teratoma + embryonal carcinoma + endodermal sinus tumour (yolk sac tumour) (TEE).
        2. seminoma + embryonal (SE).
        3. embryonal + teratoma (TE).
  • Sex-cord stromal tumour.
    • Leydig cell tumour.
    • Sertoli cell tumour.

IHC for GCTs

ABCDs of GCTs:

  • AFP - yolk sac tumour.
  • Beta-hCG - choriocarcinoma.
  • CD30 - embryonal carcinoma.
  • D2-40 - seminoma.

Intratubular germ cell neoplasia

  • Considered the precursor lesion for germ cell tumours.
  • Not all germ cell tumours (GCTs) arise from intratubular germ cell neoplasia.

The following testicular GCTs do not arise from ITCGN:

Seminoma

Epi. & etiology

  • Arises from intratubular germ cell neoplasia (ITGCN).

Microsopy

Features:

  • Cells with fried egg appearance.
    • Clear cytoplasm.
    • Central nucleus.
      • Nucleus has "corners", i.e. it is not round.
  • Lymphoctyes common, not essential.
  • May see syncytiotrophoblasts.
    • Large + many irregular or lobular hyperchromatic nuclei.
    • Eosinophilic vacuolated cytoplasm (contains hCG).
    • Closest to mom in normal chorionic villi - covers cytotrophoblast.[3]
  • May see florid granulomatous reaction.

Memory device: 3 Cs - clear cytoplasm, central nucleus, corners on the nuclear membrane.

DDx:

  • Mixed germ cell tumour.
  • Solid variant of yolk sac tumour.
    • Lacks fibrous septae and lymphocytes.[4]

IHC

  • D2-40 +ve.
  • CD117 +ve (ckit).
  • CD30 -ve.[5]
    • Done to r/o embryonal carcinoma.
  • Cytokeratins usu. -ve, may have weak focal positivity.[5]

Spermatocytic seminoma

Microscopy[6]

  • Population of three cells.
    • Small cells - look like secondary spermatocytes.
    • Medium cells with nucleoli.
    • Large cells.

Epidemiology

  • Does NOT arise from intratubular germ cell neoplasia (ITGCN)[7] - not considered a subtype of seminoma.

Yolk sac tumour

Tumour also known as endodermal sinus tumour.

Microscopy

Classic feature:

  • Schiller-Duval bodies.
    • Look like glomerulus - central blood vessel surrounded by epithelial-like cells a space and more epithelial-like cells
  • Architecure - variable.
    • Most common microcystic pattern.[8]

Image:

Variants:

  • Hepatoid pattern.[9]
    • Vaguely resembles liver.
      • Hyaline globules (light red well-circumscribed globs).
      • Bile canaculi.
  • Solid pattern.[10]
    • Vaguely resembles seminoma.

Image:

Epidemiology

  • Most common GCT in infants and young boys.

IHC

  • AFP+
  • a1-AT+
  • cytokeratin+ ???

DDx

  • Embryonal carcinoma.


Embryonal carcinoma

General

  • Affects young adults.
    • May be seen in women.

Microscopy

Features:[11]

  • Cell border indistinct.
  • Mitoses common.
  • Variable architecture:
    • Tubulopapillary,
    • Glandular,
    • Solid,
    • Embryoid bodies - ball of cells in surrounded by empty space on three sides.
  • Nuclei overlap.

Notes:

  • Cytoplasmic staining variable (eosinophilic to basophilic).

DDx

  • Yolk sac tumour.

IHC

  • Cytokeratin+ ???[12]
  • CD30+ ???


Choriocarcinoma

  • Syncytiotrophoblasts (eosinophilic cytoplasm with vacuoles (contain hCG), multiple hyperchromatic nuclei)
    • Large + many irreg. or lobular hyperchromatic nuclei
    • Eosinophilic vacuolated cytoplasm (contains hCG)
  • Cytotrophoblasts (polygonal shape, borders, clear cytoplasm, in cords, single nucleus)
    • Polygonal shaped cells in cords/masses
    • Distinct cell borders
    • Clear cytoplasm
    • Single uniform nucleus
  • +/-Hemorrhage
  • +/-Necrosis

Clinical:

  • Aggressive clinical course.

IHC

  • beta-hCG+.

Also see: Chorionic villi.

Teratoma

  • Consists of all three germ layers.
    • Endoderm.
    • Mesoderm.
    • Ectoderm.

Classification

  • Divided into:
    • Mature.
    • Immature.

Immature

  • Immature if neural tissue is present:[13]
    • Vaguely resembles pseudostratified respiratory epithelium.

Leydig cell tumour

  • Arises from interstitial cell.
  • AKA interstitial cell tumour.

Microscopic

Features:[14]

  • Vacuolization - key feature.
  • Cytoplasm - clear to eosinophilic.
  • Nucleoli common.
  • Reinke crystals, cylindrical crystalloid eosinophilic cytoplasmic bodies (not always present).

Images:

IHC

  • Inhibin-alpha.
  • Calretinin.[15][16]
  • Melan A.[17]
    • AKA MART-1.
    • Expressed in melanoma, adrenal tissue, steroid-secreting tumours.

See also

References

  1. ↑ Müller J, Skakkebaek NE, Parkinson MC (February 1987). "The spermatocytic seminoma: views on pathogenesis". Int. J. Androl. 10 (1): 147–56. PMID 3583416.
  2. ↑ Manivel JC, Simonton S, Wold LE, Dehner LP (June 1988). "Absence of intratubular germ cell neoplasia in testicular yolk sac tumors in children. A histochemical and immunohistochemical study". Arch. Pathol. Lab. Med. 112 (6): 641–5. PMID 2837162.
  3. ↑ [1]
  4. ↑ URL: http://webpathology.com/image.asp?case=34&n=8. Accessed on: March 8, 2010.
  5. ↑ 5.0 5.1 PMID 16867864.
  6. ↑ Cotran, Ramzi S.; Kumar, Vinay; Fausto, Nelson; Nelso Fausto; Robbins, Stanley L.; Abbas, Abul K. (2005). Robbins and Cotran pathologic basis of disease (7th ed.). St. Louis, Mo: Elsevier Saunders. ISBN 0-7216-0187-1.
  7. ↑ Müller J, Skakkebaek NE, Parkinson MC (February 1987). "The spermatocytic seminoma: views on pathogenesis". Int. J. Androl. 10 (1): 147–56. doi:10.1111/j.1365-2605.1987.tb00176.x. PMID 3583416.
  8. ↑ URL: http://webpathology.com/image.asp?case=34&n=1. Accessed on: March 8, 2010.
  9. ↑ URL: http://webpathology.com/image.asp?case=34&n=6. Accessed on: March 8, 2010.
  10. ↑ URL: http://webpathology.com/image.asp?case=34&n=8. Accessed on: March 8, 2010.
  11. ↑ GUP P.549
  12. ↑ NEED REF.
  13. ↑ RS. 2 May 2010.
  14. ↑ GUP P.581.
  15. ↑ URL: http://www.antibodybeyond.com/reviews/cell-markers/leydig-cell-marker.htm. Accessed on: 18 May 2010.
  16. ↑ PMID 15950053.
  17. ↑ PMID 12966351.

External links

Retrieved from "https://librepathology.org/w/index.php?title=Testis&oldid=215"