Testis
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 (AKA interstitial cell).
- Large eosinophilic cell.
- Blood vessels.
Associated structures
- Epididymis - stores the sperm.
- Pseudostratified epithelium with cilia.
Image:
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:
- teratoma + embryonal carcinoma + endodermal sinus tumour (yolk sac tumour) (TEE).
- seminoma + embryonal (SE).
- embryonal + teratoma (TE).
- Common combinations:
- 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.
Tabular summary of GCTs
| Tumour | Key feature | Microscopic | IHC | Other | Image |
|---|---|---|---|---|---|
| Intratubular germ cell neoplasia (IGCN) | nests of small fried egg cells | large central nucleus, clear cytoplasm, squared-off nuclear membrane, nucleoli[1] |
CD117 | appearance similar to seminoma | Image |
| Seminoma | fried egg cells | fried egg-like cells (central nucleus, clear cytoplasm) with squared-off nuclear membrane, nucleoli, lymphocytic infiltrate, granulomata, syncytiotrophoblastic giant cells[2] |
D2-40 | Dysgerminoma | Image |
| Yolk sac tumour (endodermal sinus tumour) | Schiller-Duval bodies | Schiller-Duval b. = central blood vessel surrounded by epithelial-like cells a space and more epithelial-like cells, variable arch. | AFP | patterns: microcystic, solid, hepatoid | hepatoid YST |
| Embryonal carcinoma | prominent nucleoli, vescicular nuclei | var. arch.: tubulopapillary, glandular, solid, embryoid bodies (ball of cells in surrounded by empty space on three sides), +/-nuclear overlap, mitoses common | CD30 | usu. part of a mixed GCT | [1], [2] |
| Choriocarcinoma | key feature | detailed micro | beta-hCG | other | image |
| Teratoma | key feature | detailed micro | None | other | image |
| Spermatocytic seminoma | population of 3 cells | pop.: (1) small scant cytoplasm, (2) medium with nucleoli, (3) large - rare | nuclei round, no nucleoli rare/none | does not arise ITGCN, no lymphocytic infiltrate (like in seminoma) | ? |
| Mixed germ cell tumour | NA | common combinations: teratoma + embryonal carcinoma + endodermal sinus tumour (yolk sac tumour) (TEE); seminoma + embryonal (SE); embryonal + teratoma (TE) | NA | - | - |
Tabular summary of (male) SCSTs
| Tumour | Key feature | Microscopic | IHC | Other | Image |
|---|---|---|---|---|---|
| Leydig cell tumour | intersitial cell cluster with eosinophilic cytoplasm | cytoplasmic vacuolization, uniform nuclei with nucleoli | MART-1, calretin, inhibin | +/-Reinke crystals (cylindrical crystalloid eosinophilic cytoplasmic bodies) | [3] |
| Sertoli cell tumour | cells in cords or trabeculae | light staining bubbly cytoplasm +/- large cytoplasmic vacuoles, granular chromatin | ? | usu. no significant nuclear atypia, no mitoses | [4] |
![[3]](http://commons.wikimedia.org/wiki/File:Leydig_cell_tumour2.jpg){kind=link}
![[4]](http://commons.wikimedia.org/wiki/File:Sertoli_cell_tumour_low_mag.jpg){kind=link}
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:
- Spermatocytic seminoma.[3]
- Yolk sac tumours (endodermal sinus tumour).[4]
- Teratoma. (???)
Microscopic
Features:[5]
- Enlarged nuclei, vesicular.
- Clear cytoplasm.
- Nucleoli, prominent.
Image(s):
Seminoma
General
- Male counterpart of the dysgerminoma, which arise in the ovary.
Epidemiology & etiology
- Arises from intratubular germ cell neoplasia (ITGCN).
Microsopy
Features:
- Cells with fried egg appearance.
- Clear cytoplasm.
- Central nucleus, with prominent nucleolus.
- Nucleus has "corners", i.e. it is not round.
- Lymphoctyes common, not essential.
- May see syncytiotrophoblasts, AKA syncytiotrophoblastic giant cells (STGCs).[6]
- Large + irregular, vesicular nuclei.
- Eosinophilic vacuolated cytoplasm (contains hCG).
- Syncytiotrophoblasts = closest to mom in normal chorionic villi - covers cytotrophoblast.[7]
- 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.[8]
IHC
- D2-40 +ve.
- CD117 +ve (ckit).
- CD30 -ve.[9]
- Done to r/o embryonal carcinoma.
- Cytokeratins usu. -ve, may have weak focal positivity.[9]
Spermatocytic seminoma
General
- Rare tumour.
- Only one case of metastases in 200 cases.[10]
- Orchiectomy is curative.
- Not reported/found in females.[10]
Epidemiology
- Does NOT arise from intratubular germ cell neoplasia (ITGCN)[11] - not considered a subtype of seminoma.
Microscopy
Features:[12]
- Population of three cells.
- Mucoid lakes.
- Intratubular spread.
Notes:
- Spireme = the tangle of filaments in prophase portion of mitosis.[13]
Images:
Yolk sac tumour
General
- Tumour also known as endodermal sinus tumour.
- Usually paediatric population.
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.[14]
Image:
Variants:
- Hepatoid pattern.[15]
- Vaguely resembles liver.
- Hyaline globules (light red well-circumscribed globs).
- Bile canaculi.
- Vaguely resembles liver.
- Solid pattern.[16]
- 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:[17]
- 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+ ???[18]
- CD30 +ve.
Choriocarcinoma
Clinical
- Aggressive clinical course.
Microscopy
- Syncytiotrophoblasts:
- Large + many irreg. or lobular hyperchromatic nuclei.
- Eosinophilic vacuolated cytoplasm (contains hCG).
- Cytotrophoblasts:
- Clear cytoplasm.
- Polygonal shaped cells in cords/masses.
- Distinct cell borders.
- Single uniform nucleus.
- +/-Hemorrhage.
- +/-Necrosis.
Image(s):
Notes:
- See: Chorionic villi.
IHC
- beta-hCG +ve.
Teratoma
- Consists of all three germ layers.
- Endoderm.
- Mesoderm.
- Ectoderm.
Classification
- Divided into:
- Mature.
- Immature.
Immature
- Immature if neural tissue is present:[19]
- Vaguely resembles pseudostratified respiratory epithelium.
- Islands of small hyperchromatic cells - "blastema".
- +/-Cartilage.
Images:
- Immature teratoma - myxomatous stroma (webpathology.com).
- Immature teratoma - blastema (webpathology.com).
- Immature teratoma - primitive neuroepithelium (webpathology.com).
Leydig cell tumour
- Arises from interstitial cell.
- AKA interstitial cell tumour.
Microscopic
Features:[20]
- Vacuolization - key feature.
- Cytoplasm - clear to eosinophilic.
- Nucleoli common.
- Reinke crystals, cylindrical crystalloid eosinophilic cytoplasmic bodies (not always present).
Images:
- Leydig cell tumour - low mag. (WC).
- Leydig cell tumour - intermed. mag. (WC).
- Leydig cell tumour - high mag. (WC).
IHC
- Inhibin-alpha.
- Calretinin.[21][22]
- Melan A.[23]
- AKA MART-1.
- Expressed in melanoma, adrenal tissue, steroid-secreting tumours.
Sertoli cell tumour
- Arises from Sertoli cells (AKA nurse cells).
Microscopic
Features:
- Groups of cells in cords or trabeculae (beam-like arrangement).
- Cells have:
- Light staining bubbly cytoplasm +/- large cytoplasmic vacuoles.
- Slightly irregular nucleoli.
- Granular irregular appearing chromatin.
Negatives:
- Mitoses are rare.
- No significant nuclear atypia.
Image(s):
See also
References
- ↑ GUP P.538.
- ↑ GUP P.542.
- ↑ Müller J, Skakkebaek NE, Parkinson MC (February 1987). "The spermatocytic seminoma: views on pathogenesis". Int. J. Androl. 10 (1): 147–56. PMID 3583416.
- ↑ 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.
- ↑ URL: http://www.webpathology.com/image.asp?case=30&n=1. Accessed on: 18 May 2010.
- ↑ GUP P.542.
- ↑ URL: http://upload.wikimedia.org/wikipedia/commons/4/45/Gray37.png. Accessed on: 31 May 2010.
- ↑ URL: http://webpathology.com/image.asp?case=34&n=8. Accessed on: March 8, 2010.
- ↑ 9.0 9.1 PMID 16867864.
- ↑ 10.0 10.1 10.2 Eble JN (October 1994). "Spermatocytic seminoma". Hum. Pathol. 25 (10): 1035–42. PMID 7927308.
- ↑ 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.
- ↑ 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.
- ↑ URL: http://www.thefreedictionary.com/spireme. Accessed on: 4 June 2010.
- ↑ URL: http://webpathology.com/image.asp?case=34&n=1. Accessed on: March 8, 2010.
- ↑ URL: http://webpathology.com/image.asp?case=34&n=6. Accessed on: March 8, 2010.
- ↑ URL: http://webpathology.com/image.asp?case=34&n=8. Accessed on: March 8, 2010.
- ↑ GUP P.549
- ↑ NEED REF.
- ↑ RS. 2 May 2010.
- ↑ GUP P.581.
- ↑ URL: http://www.antibodybeyond.com/reviews/cell-markers/leydig-cell-marker.htm. Accessed on: 18 May 2010.
- ↑ Bar-Shira Maymon B, Yavetz H, Yogev L, et al. (2005). "Detection of calretinin expression in abnormal immature Sertoli cells in non-obstructive azoospermia". Acta Histochem. 107 (2): 105–12. doi:10.1016/j.acthis.2005.02.002. PMID 15950053.
- ↑ PMID 12966351.
