Difference between revisions of "Pituitary gland"

From Libre Pathology
Jump to navigation Jump to search
Line 177: Line 177:


==Craniopharyngioma==
==Craniopharyngioma==
===General===
{{Main|Craniopharyngioma}}
*Develop from remains of Rathke's pouch or squamous epithelial cell rests.<ref name=pmid17425791>{{Cite journal  | last1 = Garnett | first1 = MR. | last2 = Puget | first2 = S. | last3 = Grill | first3 = J. | last4 = Sainte-Rose | first4 = C. | title = Craniopharyngioma. | journal = Orphanet J Rare Dis | volume = 2 | issue =  | pages = 18 | month =  | year = 2007 | doi = 10.1186/1750-1172-2-18 | PMID = 17425791 }}</ref>
 
Comes in two flavours:<ref name=pmid17425791/>
*Adamantinomatous type.
**Adults and children. 
*Squamous papillary type.
**Adults individuals.<ref name=pmid6696166>{{Cite journal  | last1 = Giangaspero | first1 = F. | last2 = Burger | first2 = PC. | last3 = Osborne | first3 = DR. | last4 = Stein | first4 = RB. | title = Suprasellar papillary squamous epithelioma ("papillary craniopharyngioma"). | journal = Am J Surg Pathol | volume = 8 | issue = 1 | pages = 57-64 | month = Jan | year = 1984 | doi =  | PMID = 6696166 }}</ref>
**Usually solid.
 
Radiology:<ref name=pmid17425791/>
*Calcified - adamantinomatous type only.
*Solid & cystic.
 
===Microscopic===
====Adamantinomatous====
Features (adamantinomatous):<ref name=Ref_DCHH184>{{Ref DCHH|184}}</ref>
*Well-circumscribed (or pseudoinvasive border).
*Multicystic.
*Small-to-medium sized cells with moderate amount of basophilic cytoplasm.
*Bland nuclei (with occ. small nucleoli).
*"Wet" keratin - nests of whorled keratin.
*Calcifications (non-psammomatous).
 
=====Images=====
<gallery>
Image:Adamantinomatous_craniopharyngioma_-_very_low_mag.jpg | Adamantinomatous craniopharyngioma - very low mag. (WC/Nephron)
Image:Adamantinomatous_craniopharyngioma_-_intermed_mag.jpg | Adamantinomatous craniopharyngioma - intermed. mag. (WC/Nephron)
Image:Adamantinomatous_craniopharyngioma_-_very_high_mag.jpg | Adamantinomatous craniopharyngioma - very high mag. (WC/Nephron)
</gallery>
====Papillary====
Features (papillary):<ref name=Ref_PSNP406>{{Ref PSNP|406}}</ref>
*Non-keratinized squamous epithelium (without nuclear atypia).
*Fibrovascular cores (required for ''papillary'').
 
Notes:
*+/-Cilia (rare).
*+/-Goblet cell-like formations (rare).
 
=====Image=====
<gallery>
Image:Papillary_craniopharyngioma_-_intermed_mag.jpg |Papillary craniopharyngioma - intermed. mag. (WC/Nephron)
Image:Papillary_craniopharyngioma_-_very_high_mag.jpg |Papillary craniopharyngioma - very high mag. (WC/Nephron)
</gallery>
www:
*[http://library.med.utah.edu/WebPath/jpeg4/ENDO115.jpg Craniopharyngioma (med.utah.edu)].<ref>URL: [http://library.med.utah.edu/WebPath/jpeg4/ENDO115.jpg http://library.med.utah.edu/WebPath/jpeg4/ENDO115.jpg]. Accessed on: 6 December 2010.</ref>


==Autoimmune hypophysitis==
==Autoimmune hypophysitis==

Revision as of 21:10, 11 November 2013

The pituitary gland is known as the master gland.

Divisions:[1]

  • Anterior pituitary (AKA adenohypophysis).
  • Posterior pituitary (AKA neurohypophysis, neural pituitary).

Function

Anterior

Hormones:[2]

  • Growth hormone (GH).
  • Luteinizing hormone (LH)
  • Follicle-stimulating hormone (FSH)
  • Thyroid stimulating hormone (TSH)
  • Adrenocorticotropic hormone (ACTH)
  • Prolactin (PRL)

Mnemonic: "Go Look For The Adenoma Please" = GH, LH, FSH, TSH, ACTH, PRL.

Posterior

Hormones:[2]

  • Oxytocin.
  • Antidiuretic hormone (ADH).

Anatomy and histology

Anatomy

Basic anatomy (simplified):[3]

  • Anterior:
    • Pars distalis.
    • Pars intermedia.
  • Posterior:
    • Pars nervosa.

Embryological origin:[3]

  • Anterior - Rathke's pouch (roof of mouth).
  • Posterior - diencephalon (ventral aspect).

Images:

Histology

Anterior

  • Acidophils (40% of cells) = red or orange.
    • GH, PRL.
  • Basophils (10% of cells) = basophilic (light blue).
    • TSH, LH, FSH, ACTH.
  • Chromophobes (50% of cells) = amphophilic (purplish/grey).

Notes:

  • The cellular product (i.e. hormone produced) is not strictly correlated with the cell type.[4]
  • The cells can be typed using IHC; somatotrophs (GH), lactotrophs (PRL), corticotrophs (ACTH), thyrotrophs (TSH), gonadotrophs (FSH, LH).[5]

Posterior

Features:[4]

  • Herring bodies - key feature.
    • Eosinophilic axonal dilations filled with lysosomes and neurosecretory granules.
  • Less cellular.
    • Usually more cellular in perivascular location.

Image: Herring bodies (ouhsc.edu).

DDx for stellar lesions

Pituitary necrosis

  • Rare.

Causes of pituitary necrosis

  • Sheehan syndrome - secondary to blood loss in childbirth.[6]
  • Syphilis (fetal-maternal transmission).[7]
  • Mollaret's meningitis - very rare.[8] (???)
  • Spontaneous necrosis of pituitary tumours - case reports.[9]

Images:

Specific entities

Pituitary adenoma

General

  • Clinical:[10]
    • Classically: visual field defects (bitemporal hemianopsia).
    • Others (increased intracranial pressure): headache, nausea, vomiting.

Classification:

  1. Microadenoma <= 1 cm.
  2. Macroadenoma > 1 cm.

Notes:

  • May be classified by what they secrete. Cushing disease is due to pituitary gland hypersecretion of ACTH (due to a pituitary adenoma or CRH hypersecretion from the hypothalamus).[11] Cushing syndrome is hypercortisolism not due to pituitary gland pathology.

Familial pituitary adenomas

A pituitary adenoma may be part of a familial syndrome:[12][13]

Syndrome Gene Notes
Multiple endocrine neoplasia I MEN1 characterized by the 3 Ps: pituitary adenoma, parathyroid adenoma, pancreatic neuroendocrine tumour
MEN-1-like syndrome CDKN1B[14] also known as Multiple endocrine neoplasia IV [14]
Carney syndrome PRKAR1A other findings (mnemonic NAME): nevi, atrial myxoma, myxoid neurofibroma, ephelides (freckles)
Isolated pituitary adenoma[15] AIP classically GH-producing adenoma - leads to acromegaly

Microscopic

Features:[16]

  • Loss of fibrous stroma.
    • The cells of a normal (anterior) pituitary are nested.

Notes:

  • Smears very well.[17]

Images

www:

Stains

  • Reticulin - loss of reticulin between tumour cells.

IHC

  • LH.
  • FSH.
  • TSH.
  • GH.
  • Prolactin.
  • ACTH - Cushing disease.

Rathke cleft cyst

General

  • Benign counterpart of craniopharyngioma.
  • Arises from intermediate lobe of pituitary gland (pars intermedia of pituitary gland).

Radiology:

  • Typically no calcifications.[18]

Radiologic DDx:[18]

Microscopic

Features:

  • Lined by a layer of cuboidal or columnar epithelial with cilia.
  • +/-Goblet cells.[19]
  • +/-Squamous metaplasia ~ may be several layers thick.
  • Cholesterol clefts may be seen in association with rupture.[21]

DDx:

Images:

Craniopharyngioma

Autoimmune hypophysitis

General

Features:[22]

  • Rare.
  • Autoantigens are unknown.
  • May be misdiagnosed as a nonsecreting adenoma.

Microscopic

Features:[22]

  • Lymphocytic infiltration.

See also

References

  1. http://www.vivo.colostate.edu/hbooks/pathphys/endocrine/hypopit/histo.html
  2. 2.0 2.1 http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/P/Pituitary.html
  3. 3.0 3.1 URL: http://www.vivo.colostate.edu/hbooks/pathphys/endocrine/hypopit/histo_pit.html. Accessed on: 31 October 2010.
  4. 4.0 4.1 Perry, Arie; Brat, Daniel J. (2010). Practical Surgical Neuropathology: A Diagnostic Approach: A Volume in the Pattern Recognition series (1st ed.). Churchill Livingstone. pp. 26. ISBN 978-0443069826.
  5. Kumar, Vinay; Abbas, Abul K.; Fausto, Nelson; Aster, Jon (2009). Robbins and Cotran pathologic basis of disease (8th ed.). Elsevier Saunders. pp. 1098-9. ISBN 978-1416031215.
  6. URL: http://www.mayoclinic.com/health/sheehans-syndrome/DS00889. Accessed on: 16 November 2010.
  7. URL: http://pediatrics.aappublications.org/cgi/content/full/104/1/e4. Accessed on: 16 November 2010.
  8. Dancer CM, Woods ML, Henderson RD, Robertson T, Mungomery M, Allworth A (July 2008). "Mollaret's meningitis and pituitary failure associated with a Rathke's cleft cyst". Intern Med J 38 (7): 609–11. doi:10.1111/j.1445-5994.2008.01709.x. PMID 18715308.
  9. Sachdev Y, Evered DC, Hall R (April 1976). "Spontaneous pituitary necrosis". Br Med J 1 (6015): 942. PMC 1639254. PMID 1268492. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1639254/pdf/brmedj00512-0028a.pdf.
  10. Kumar, Vinay; Abbas, Abul K.; Fausto, Nelson; Aster, Jon (2009). Robbins and Cotran pathologic basis of disease (8th ed.). Elsevier Saunders. pp. 1100. ISBN 978-1416031215.
  11. Kumar, Vinay; Abbas, Abul K.; Fausto, Nelson; Aster, Jon (2009). Robbins and Cotran pathologic basis of disease (8th ed.). Elsevier Saunders. pp. 1148. ISBN 978-1416031215.
  12. Elston, MS.; McDonald, KL.; Clifton-Bligh, RJ.; Robinson, BG. (Aug 2009). "Familial pituitary tumor syndromes.". Nat Rev Endocrinol 5 (8): 453-61. doi:10.1038/nrendo.2009.126. PMID 19564887.
  13. Mitchell, Richard; Kumar, Vinay; Fausto, Nelson; Abbas, Abul K.; Aster, Jon (2011). Pocket Companion to Robbins & Cotran Pathologic Basis of Disease (8th ed.). Elsevier Saunders. pp. 554. ISBN 978-1416054542.
  14. 14.0 14.1 Online 'Mendelian Inheritance in Man' (OMIM) 600778
  15. Korbonits, M.; Storr, H.; Kumar, AV. (May 2012). "Familial pituitary adenomas - Who should be tested for AIP mutations?". Clin Endocrinol (Oxf). doi:10.1111/j.1365-2265.2012.04445.x. PMID 22612670.
  16. Perry, Arie; Brat, Daniel J. (2010). Practical Surgical Neuropathology: A Diagnostic Approach: A Volume in the Pattern Recognition series (1st ed.). Churchill Livingstone. pp. 36. ISBN 978-0443069826.
  17. MUN. 24 November 2010.
  18. 18.0 18.1 URL: http://emedicine.medscape.com/article/343629-overview. Accessed on: 14 November 2010.
  19. URL: http://www.endotext.org/neuroendo/neuroendo3/neuroendo3.html. Accessed on: 27 May 2010.
  20. Perry, Arie; Brat, Daniel J. (2010). Practical Surgical Neuropathology: A Diagnostic Approach: A Volume in the Pattern Recognition series (1st ed.). Churchill Livingstone. pp. 408. ISBN 978-0443069826.
  21. URL: http://path.upmc.edu/cases/case177/dx.html. Accessed on: 8 January 2012.
  22. 22.0 22.1 Tzou SC, Lupi I, Landek M, et al. (July 2008). "Autoimmune hypophysitis of SJL mice: clinical insights from a new animal model". Endocrinology 149 (7): 3461–9. doi:10.1210/en.2007-1692. PMC 2453094. PMID 18388197. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2453094/.

External links