Adrenal gland

A drawing of the adrenal glands.

Adrenal gland is a little organ that hangs-out above the kidney. Pathologists rarely see it. It uncommonly is affected by tumours.

Anatomy & histology

Adrenal cortical rest redirects here.

Anatomy

• Cortex.
• Medulla.

Note:

• Adrenal tissue may be associated with gonads or between gonads and adrenal gland proper.

Microscopic

It is composed of a cortex and a medulla.

Cortex

It has three layers - mnemonic: GFR (from superficial to deep):

1. Zona glomerulosa - salt (e.g. aldosterone).
   • Eosinophilic cytoplasm. (???)
   • Layer normally discontinuous.
2. Zona fasciculata - sugar (e.g. cortisol).
   • Clear cytoplasm - key feature.
   • Largest part of the cortex ~ 70%.
   • Cells in cords/nests. (???)
3. Zona reticularis - steroid (e.g. dehydroepiandrosterone).
   • Marked eosinophilia of cytoplasm - key feature.
   • Granular/reticular cytoplasm.

Note:

• Normal cortex may not be completely encapsulated, i.e. the adrenal capsule may have defects.
  • In other words: the cortex may "spill" into the surrounding fat.

Medulla

It consists of two cell types:

1. Chromaffin cells.
   • Arise of neural crest.
2. Sustentacular cells (supporting cells).

Produce NED: norepinephrine, epinephrine, dopamine.

Images

• 

  Adrenal medulla. (WC)

• 

  Adrenal cortex & medulla (right of image), and tumour (left of image). (WC/Nephron)

• 

  Adrenal rest - low mag. (WC/Nephron)

www

• Adrenal medulla (webpathology.com).

IHC

Adrenal cortex:

• Chromogranin A -ve.
• Synaptophysin +ve.
• Alpha-inhibin +ve.
• Vimentin +ve.
• Melan A +ve.
• AE1/AE3 -ve.

Clinical

Patients getting a bilateral adrenalectomy get pre-treatment with steroids.

Adrenal insufficiency is an immediate danger post-op.

Benign

The section covers non-neoplastic pathologies of the adrenal gland. These uncommonly come to the pathologist.

• Adrenal incidentalomas
  • Adrenal tumors
  • Greater than 1 cm
  • Identified on imaging performed for other indications
• Found in up to 10% of patients undergoing abdominal imaging.
• Management problematic
  • Guidelines incorporate lesion size, functional status and imaging features.
  • Resection is generally advocated for
    • Functioning lesions.
    • Radiographic features suggestive of malignancy.
    • Growth during observation.

Stress response

• In fetuses - fat content increases due to stress -- see: Fetal_autopsy#Adrenal_fetal_fat_pattern.
• In newborns/children/adults - fat content decreases due to stress.

Spironolactone bodies

Main article: Spironolactone bodies

Hemorrhagic adrenalitis

• AKA Waterhouse-Friderichsen syndrome.

General

• Classically thought to be only due to Neisseria meningitidis; however, more recently also associated with Staphylococcus aureus, and Streptococcus pneumoniae.

Gross

Features:

• Massive haemorrhage within the substance of the adrenal gland.

DDx (autopsy):

• Post-mortem changes.

Microscopic

Features:

• Massive haemorrhage within the substance of the adrenal gland.

Image: Haemorrhage in adrenal (nih.gov).

• 

  Adrenal hemorrhage -low power - E. coli sepsis (SKB)

• 

  Adrenal hemorrhage - medium power - E. coli sepsis (SKB)

Adrenal cytomegaly

• AKA adrenocortical cytomegaly.
• AKA adrenal gland with cytomegaly.

General

May be associated with:

• Beckwith-Wiedemann syndrome.
• Prematurity.
• Rh-incompatibility.

Microscopic

Features:

• Large cells in the adrenal cortex.

Addison disease

General

• Chronic adrenocortical insufficiency.

Clinical:

• Brown skin - due POMC (a precursor of ACTH and melanocyte stimulating hormone (MSH)).
  • POMC presence implies the pituitary gland intact.
• Hypotension.
• Nausea and vomiting.

DDx:

• Autoimmune.
• Tuberculosis.
• AIDS.
• Malignancy.

Notes:

• Secondary adrenocortical insufficiency (due to pituitary pathology):
  • No hyperpigmentation (as no POMC).
  • Aldosterone usu. normal.

Microscopic

Features:

• Atrophy adrenal cortex - specifically zona fasciculata and zona reticularis.

Notes:

• There is preservation of zona glomerulosa and medulla.

Benign neoplasms

Adrenal hemangioma

Radiographic incidentalomas but may be large and calcified raising a radiographic ddx of adrenal cortical carcinoma.

• Rare.
• 40 and 70 years.
• 2:1 female-to-male ratio

• 

  Adrenal hemangioma - low power (SKB)

• 

  Adrenal hemangioma - medium power (SKB)

Adrenal cortical adenoma

Main article: Adrenal cortical adenoma

Pheochromocytoma

Main article: Pheochromocytoma

Adrenal ganglioneuroma

Main article: Ganglioneuroma

General

• May be retroperitoneal.
• Multiple ganglioneuromas may be due to multiple endocrine neoplasia IIb.

Gross

• Solid.
• White.
• Firm.
• Well-circumscribed.
• May be nodular.

DDx (gross):

• Leiomyoma.

Images:

• Adrenal ganglioneuroma (WC).
• Ganglioneuroma (webpathology.com).

Microscopic

Features:

• Ganglion cells - key feature.
  • Large cells with large nucleus.
    • Prominent nucleolus.
• Disordered fibrinous material.

Images:

• Ganglion - benign (WC).

Adrenal myelolipoma

Main article: Adrenal myelolipoma

Adenomatoid tumour

See: Adenomatoid tumours (uterine tumours).

Malignant neoplasms

Adrenocortical carcinoma

• AKA adrenal cortical carcinoma.
• Abbreviated ACC.

Main article: Adrenocortical carcinoma

Neuroblastoma

Main article: Neuroblastoma

See also

• Small round cell tumours.