Adrenal Gland Tumors😍

Adrenal Gland Tumors

Adrenal Incidentaloma

• Incidentally detected adrenal tumour.

Adrenal adenoma

• The most common incidental adrenal lesion detected.

• Features:
• Fat-containing.
• Rapid wash-in and rapid wash-out of the contrast.

• Hounsfield unit (HU)
• Negative or <10 is considered → adrenal adenoma.
• If > 10 → take a delayed scan → shows ↑sed washout, s/o
• Low lipid Adrenal adenoma

Pheochromocytoma

• Lightbulb sign on T2 weighted MRI (T2W MRI).

• hyperintense in T2ZW MRI

• BIOPSY/FNAC → Contraindicated

Category	Investigation	Notes
Screening Test/ Initial	24-hour urine fractionated metanephrine. >> 24 hr urine VMA	Sensitivity and specificity: 98%.
Confirm → IOC/ Best investigation	Serum plasma free metanephrines	Most sensitive test 100% sensitivity.
Best / Radiological IOC	MRI abdomen.	Shows light bulb sign
IOC for Extra-adrenal Pheo	Gallium dotatate (DOTANOC) PET scan scan → detect somatostatin receptors / Tc 99 Dopa PET	Best for detecting metastasis/extra-adrenal sites
FOR METS	(Nucleotide scan) Metaiodobenzylguanidine (MIBG) scintigraphy	ㅤ
Localise Extra adrenal Pheo or mets	Radeon	ㅤ

Workup

• Serum cortisol.

• Plasma free metanephrines (to rule out phaeochromocytoma).

• Serum DHEA.

• Dexamethasone suppression test (Cushing's syndrome).

• Urinary cortisol.

• Functional Tumour: Manage accordingly.

• Non-functional tumour: MRI (Check for malignancy).

Radiological features suspicious of malignancy

• Diameter >4 cm and density >10 HU.

• CECT: Wash out.

• MRI chemical shift: No change in signal intensity on out of phase imaging.

• FDG PET: Positive uptake.

Management (U/L adrenal mass)

Radiological suspicion of malignancy: YES

• Local invasion:
• YES → Open adrenalectomy.

• Local invasion: NO:
• Diameter ≤6 cm: Open adrenalectomy.
• Diameter >6 cm: Individualized Sx approach.

Radiological suspicion of malignancy: NO

• Functional tumour:
• YES → Laparoscopic adrenalectomy.

• Functional tumour: NO:
• Imaging >25% ↑ in size:
• Laparoscopic adrenalectomy.
• Imaging <25% ↑ in size: 
• Monitor.

Neuroblastoma

One liners

• M/C abdominal malignancy in children:
• Neuroblastoma > Wilms tumour.

• Most common extra-cranial solid tumor in children.

• Second most common solid tumor in children
• [Most common: intracranial/brain Tumors]

• Most common malignancy in infancy.

Features

• M/C age: <5 years.

• Genetics: Shows N-MYC amplification.
• Mnemonic: N for N-MYC

Site of Involvement

• Site: Adrenal medulla > Sympathetic chain.

• Cell of origin: Neuroblasts (derived from neural crest tissue).

• Organs involved:
1. Adrenal gland
• AKA suprarenal tumor.
• most common 
2. Paravetebral sympathetic chain/ganglia
• second most common
3. Posterior mediastinum.
4. Pelvis.

Clinical Features

• Abdominal lump crossing midline 
• Wilms tumour: Does not cross

• >50% present with metastasis.

• Horner's syndrome: Anhydrosis, miosis, and ptosis.

• Heterochromia iridis: Variation in color of the two irises.

• Constitutional symptoms: Fever, weight loss, irritability.

Paraneoplastic Manifestations

• Myoclonus Opsoclonus ataxia.
• AKA dancing eye/dancing feet syndrome.
• Associated with anti-neuronal antibodies.

• VIP (Vasoactive intestinal polypeptide) hypersecretion
• Intractable watery diarrhea, hypokalemia.

Metastatic features

• Blueberry muffin lesions on skin
• Characteristic Skin Mets

• Raccoon eyes.
• peri-orbital swelling and ecchymosis
• retro-orbital region with infiltration 

• To bone (most common site) → Bony pain.

Investigations

• Urine markers
• initial investigation
• Metabolites of catecholamines (non specific):
• VMA (vanillylmandelic acid).
• HVA (homovanillic acid).

• NSE (Neuron specific enolase)
• Most specific.

IOC: 

• MRI (Tumour site, intratumoral calcifications).

CT abdomen (most common):

• Midline

• Encased vessels

• Stippled calcifications.

• Tumor mass displacing kidney inferolaterally
• (not seen in wilm's tumor).

Radionuclide scan

• ¹³¹MIBG (Meta Iodo Benzyl Guanidine) scintigraphy 

• To rule out metastases.

• M/c mets to bones

MIBG

Gross:

• Solid tumor.

Microscopy:

• Small, round, uniform blue cells.
• Scanty cytoplasm + hyperchromatic nuclei.

• Differential Diagnosis
• For small round uniform blue cells: → Starry sky pattern on biopsy
• Mnemonic: BLUE → BLRE
• Rhabdomyosarcoma
• Ewing's sarcoma/PNET
• Lymphoma
• Blastemal tumour group
• Neuroblastoma,
• Retinoblastoma,
• Hepatoblastoma,
• Medulloblastoma,
• Nephroblastoma /Wilms tumour

• Exhibits Homer-Wright pseudorosettes 
  (cells arranged in rosettes with pink material in center).



• Homer Wright rosettes or pseudomedullary rosettes
• Center → filled
• Mnemonic: Psudo friends → hide something inside their heart

 



• Flexner Winterstener Rosette
• Center → Pale or white
• Mnemonic: True friends wants what is good for you → heart (centre) is pure white
• Found in small round blue cell tumor

• Homer-Wright → pseudo rosettes.

• Mnemonic: MEN () R () Wright () and Men are Pseudo, Men are Blast
• Medulloblastoma
• Ewings/Ependymoma
• Neuroblastoma
• Retinoblastoma
• (Both rosettes → seen in Retinoblastoma).

Prognostic factors of neuroblastoma.

Mx

• Localised → Surgical resection of tumor.

• Disseminated → Surgery + Chemotherapy

• Dinutuximab:
• Mab against GD2 Glycolipid

Pheochromocytoma

 

• Adrenal gland tumor that produces epinephrine

• Neural crest cell tumor.

• Secretes catecholamines or their metabolites.

Origin and Types

• Adrenal Pheochromocytoma:
• Arises from chromaffin cells of the adrenal medulla (75% of cases).

• Extra-Adrenal Pheochromocytoma (Paraganglioma):
• Arises from ganglia (25% of cases).
• Types:
• Sympathetic ganglia:
• 20% of all pheos
• M/C site: Organ of Zuckerkandl (Sympathetic Chain)
• Have high malignant potential
• Parasympathetic ganglia:
• Most common sites: Carotid body or jugular bulb

Associated Syndromes

• MEN 2 (m/c).
• B/L

• Neurofibromatosis-1.
• U/L

• Von-Hippel-Lindau Syndrome.
• B/L

• Familial paraganglioma syndrome.

Rule of 10s (Classic):

• Update: 25% familial (not included in the classic 10% rule)

• 10% bilateral.
• But 50% in syndromic

• 10% in children.

• 10% extra-adrenal (referred to as paraganglioma).
• M/c site → Organ of Zuckerkandl

• 10% malignant.
• 40% in familial

• 10% do not cause hypertension

Familial pheochromocytoma

• Mutations in succinate dehydrogenase complex genes
• Also associated with Paragangliom

Clinical Features

• Palpitation: HR ↑

• Headache (m/c symptom).
• paroxysmal/episodic,
• vasoconstriction

• Diaphoresis: ++sweating
• Mnemonic: PHD

• Misdiagnosis: Anxiety neurosis

• Weight loss

• Nausea, vomiting, abdominal pain

• Tremors

• Episodic HTN (m/c sign) in young patients

• Note: Young onset HTN D/D → Hyperthyroidism, renal artery stenosis, polycystic kidney disease, phaeochromocytoma.

• Impaired glucose tolerance (↑FBS, 2 hr value)

• Late: Orthostatic hypotension

Gross:

• Yellow/tan brown in color

• Areas of necrosis & hemorrhage.

• Chromaffin reaction
• Fresh tissue incubated in dichromate solution
• Yellow brown colour
• Due to release of catecholamine

Catecholamine Secretion Profile

• Adrenal Pheochromocytoma:
• Secretes adrenaline > noradrenaline.

• Extra-adrenal Pheochromocytoma:
• Exclusively secretes noradrenaline.

• Pulsatile release of catecholamines is characteristic.

Investigation

• Lightbulb sign on T2 weighted MRI (T2W MRI).

• hyperintense in T2ZW MRI

• BIOPSY/FNAC → Contraindicated

Category	Investigation	Notes
Screening Test/ Initial	24-hour urine fractionated metanephrine. >> 24 hr urine VMA	Sensitivity and specificity: 98%.
Confirm → IOC/ Best investigation	Serum plasma free metanephrines	Most sensitive test 100% sensitivity.
Best / Radiological IOC	MRI abdomen.	Shows light bulb sign
IOC for Extra-adrenal Pheo	Gallium dotatate (DOTANOC) PET scan scan → detect somatostatin receptors / Tc 99 Dopa PET	Best for detecting metastasis/extra-adrenal sites
FOR METS	(Nucleotide scan) Metaiodobenzylguanidine (MIBG) scintigraphy	ㅤ
Localise Extra adrenal Pheo or mets	Radeon	ㅤ

Neuroendocrine Tumors

 

• Pheochromocytoma

• Paraganglioma

• Carcinoid tumor

• Carotid body tumor





• Lyre sign on angiography : Splaying of carotids.

• Highly vascular tumor.

• Small cell carcinoma of lung

• Most functional Pancreatic tumor → Insulinoma

• Medullary Carcinoma Thyroid

Imaging

• Best → PET >> MRI

Microscopy:

• Nesting pattern (Zellballen pattern)
• Cells within a Nest
• Fibrous septa (Lined by flattened sustentacular cells)
• Speckled chromatin (Salt and pepper chromatin)

Two types of cells within nests:

1. Chief cells:
• Main neuroendocrine cells 
• Neuroendocrine markers:
• Synaptophysin
• Chromogranin
• Bombesin
• CD56, CD57,
• NSE
• New marker for NET:
• INSM1 (nuclear)
• Mnemonic:
• NET (NET) ittu pidichu → Bombitt () sincheyth () 56, 57 () vayssulla alkkare kollunnu → To Nicely (NSE) End Colorful (chromogranin) Insan (INSM1)

2. Sustentacular cells:
• Supporting cells,
• S100 positive.

Electron Microscopy:

• Shows dense neurosecretory granules (black granules).

Mnemonic:

• Selven (Zellballen pattern) Chrome (Feochromo) use cheythapo Net (NET) poi

• Chief (chief cells) avane suspend (sustentacular cells) cheyythu 100 (s100) divasathekk

• Para vachatha (Paraganglioma)

• Pullikk Small (Small cell) car (Carcinoid, Carotid body) ee ollu

• Pullikk oru PET (PET) um ind

Management

• Treatment of Choice:
• Laparoscopic → retroperitoneal approach
• Open adrenalectomy → If malignancy.

Pre-operative Preparation

• α blockade f/b β blockade.

• Alpha Blockers:
• Start 7-10 days before surgery.
• Phenoxybenzamine (nonselective) is the Drug of Choice (DOC).
•  → ↑ Dose gradually till postural hypotension.

• Beta Blockers:
• Start 2-3 days before surgery
• Beta after Alpha blockade
• Atenolol is commonly used.

• Fluid Replacement:
• Correct intravascular volume depletion by administering a large volume of fluids.

Management of Hypertensive Crisis

• IV Sodium nitroprusside (most important)

• IV Nicardipine.

• IV Phentolamine.

Post-operative Follow-up

• Follow up with 24-hour urine fractionated metanephrine.