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By;Col Abrar Zaidi
ADRENAL MEDULLA SURGICAL CONDITIONS CLINICAL FEATURES INVESTIGATIONS MANAGEMENT
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SEQUENCE
• INTRODUCTION• SURGICAL CONDITIONS
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INTRODUCTION
It is an overview with stress on certain
important surgical aspects
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Surgical importance why study this subject again ?
• Not an uncommon occurrence• All ages and both genders• Retroperitoneal masses• Incidental finding• Vague symptoms/diagnostic challenge
INTRODUCTION
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• The adrenal glands are bilateral, endocrine glands located near the upper pole of each
kidney• Each weighs 3–5 g and is bright yellow in color. • Vascular supply- Numerous small arteries from
the inferior phrenic artery, the aorta, and the renal artery.
• The right adrenal vein enters the posterior aspect of the vena cava; the left adrenal vein enters the left renal vein.
• Two main parts – cortex and medulla
INTRODUCTIONSURGICAL ANATOMY-ADRENALS
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INTRODUCTIONSURGICAL ANATOMY-ADRENALS
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• Adrenal Cortex• Adrenal Medulla
INTRODUCTIONSURGICAL ANATOMY-ADRENALS
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INTRODUCTIONSURGICAL ANATOMY-ADRENALS
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ADRENAL CORTEX
There are three cortical zones:• Zona glomerulosa, (aldosterone),• Zona fasciculata (cortisol). • Zona reticularis (sex steroids),
INTRODUCTIONSURGICAL ANATOMY-ADRENALS
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ADRENAL MEDULLA• Extremely vascular • consists largely of a reticular network of
catecholamine-secreting chromaffin cells with• Closely related plexus of venous sinusoids .
This facilitates release of catecholamines into the circulation. • Rich nerve supply derived mainly from the coeliac
and renal plexuses. The nerve endings terminate directly on the chromaffin cells
• synthesis and storage of catecholamines. adrenaline +smaller quantities of noradrenaline .
• Release - in flash of seconds
INTRODUCTIONSURGICAL ANATOMY-ADRENALS
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INTRODUCTIONSURGICAL ANATOMY-ADRENALS
ECTOPIC ADRENAL TISSUE The incidence of extra-adrenal medullary
tissue is very high compared to the incidence of extra-adrenal cortical tissue
Functioning extra-adrenal medullary tissue occurs in about 1 in 8 cases of medullary hyperfunction, it occurs in fewer than 1 in 1000 cases of adrenocortical hyperfunction.
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INTRODUCTIONPHYSIOLOGY-ADRENAL MEDULLAThe sympatho-adrenal system consists of:1- A sympathetic- neuronal component that uses
norepinephrine as the main neurotransmitter and 2- Adreno-medullary secretory hormone, epinephrine,
the main hormone secreted into the bloodstream. The system influences; cardiovascular, metabolic, and visceral activity, and
its typical effects are observed during severe stress. Release of norepinephrine at sympathetic nerve
endings is critical for maintenance of normal blood pressure, especially during upright posture.
Epinephrine metabolites (e.g., nor-meta-nephrine, meta-nephrine, and VMA) are excreted with catecholamines in the urine.
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SPECTRUM OF ADRENALS FUNCTIONS
• PITUTARY ADRENAL AXIS [ACTH]• RENO-ADRENAL CONNECTION [Aldos]• SYMPATHATIC CONNECTION [ Coeliac & renal plexuses con. With chromaffin cells]
INTRODUCTION
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INTRODUCTIONFUNCTIONS OF ADRENALS
• METABOLISM & IMMUNE RESPONSE human stress
response• FLUID & ELECTROLYTES • VASCULAR VOLUME,BLOOD
PRESSURE • SEXUAL FUNCTION
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SURGICAL CONDITIONS
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• Hypofunction Developmental /Acquired Agenesis,Anaplasia/
Hypoplasia• Hyperfuction• Mass Effects
SURGICAL PATHOLOGYADRENAL MEDULLA
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Loss of Medulary tissue –1. Fulminant infections2. Tumour invasion
/compression
SURGICAL PATHOLOGYADRENAL MEDULLA
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MEDULLARY-HYPERFUNCTION
Clinical conditions
1. Increased catecholamines action2. Adrenal medullary
tumours/masses Adenoma carcinoma
SURGICAL PATHOLOGYADRENAL MEDULLA
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ADRENAL TUMOURS PRIMARY VS SECODARIES
BENIGN VS MALIGNANT
SURGICAL PATHOLOGYADRENAL MEDULLA
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ADRENAL TUMOURS- FACTS • INCIDENTELOMAS- 0.6 percent of abdominal USG or CT
scans
• Most are usually benign, nonfunctional adenomas (autopsy incidence 10 percent).
• Careful history and physical examination• Determinations of the 24-h urine for free cortisol level
(Cushing's syndrome), vanillylmandelic acid (VMA), and catecholamines (pheochromocytoma).
• Aldosterone and renin should be measured in any patient with hypertension or hypokalemia.
• A mass larger than 5 cm may be carcinoma and should be resected.
• Smaller masses should be remeasured by CT in 6 months and resected if larger or left alone if unchanged.
• If pheochromocytoma is excluded and metastatic disease is suspected, a fine-needle aspiration (FNA) may be helpful .
SURGICAL PATHOLOGYADRENAL MEDULLA
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TUMOURS OF THE ADRENAL MEDULLA
A-Neoplasms of the sympathetic neurons: 1-Ganglioneuroma, 2-Neuroblastoma (sympatheticoblastoma)B-Neoplasm of chromaffin cells: Phaeochromocytoma.
NEURONAL TUMOURS –CHROMAFFIN TUMOURS
SURGICAL PATHOLOGYADRENAL MEDULLA
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SURGICAL PATHOLOGYADRENAL MEDULLA
Clinical presentation in general
• An unsuspected tumor that is found on a CT scan performed for another reason: As CT scan evaluation of the abdomen has become widespread, an unsuspected swelling of the adrenal gland is frequently detected in many patients. These tumors should be carefully evaluated.
• Production of symptoms due to over secretion of hormones from the tumor: The adrenal gland may produce distinct syndromes based on the profile of the hormones that are secreted by the tumor.
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Tumours occurring at any age
• A relatively benign. • Symptom less• Grows to a large size • A type of retroperitoneal sarcoma • Only15 per cent involve the adrenal• Most occur in other position along the sympathetic chain. • cured If removed early
GANGLIONEUROMA
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Tumours occurring in infants and children• Malignant tumour of neural crest origin • Arise from sympathetic nervous tissue from the
orbit to the pelvis. • Three-quarters arise in the abdomen and half of
these from the adrenal gland. • The most common solid tumour of infancy and
childhood, and the most common in the newborn. • The incidence is approximately 1 per 10 000 live
births. • Ninety per cent of cases of neuroblastoma occur
under the age of 8; over half occur in children under 2 years.
NEUROBLASTOMA
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• An abdominal mass - pain and distension Three-quarters of patients
• Metastatic spread: via lymphatics and bloodstream, occurs at an early stage, and approximately 70 per cent of cases have metastases at the time of initial diagnosis .
• Weight loss, failure to thrive,• Fever and anaemia may be present.• Hypertension, flushing, general irritability sweating
Excessive catecholamine production, and. • watery diarrhoea and hypokalaemia -some tumours
produce VIP, which results in. • Acute cerebellar ataxia characterised by opsomyoclonus
and chaotic nystagmus or the ‘dancing eye syndrome is an unusual manifestation of neuroblastoma of unknown cause.
NEUROBLASTOMA - CLINICAL FEATURES
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NEUROBLASTOMA CLINICAL FEATURES Abdominal neuroblastomasThe most
common presenting symptom is an abdominal or flank mass.
Thoracic neuroblastoma - a posterior mediastinal mass on chest radiograph and may cause respiratory distress or cord compression.
Neck tumor - presents with a cervical mass. Pelvic tumor - usually involves the organ of
Zuckerkandl.
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NEUROBLASTOMA -DIAGNOSIS.• cate cholamine metabolites in the urine. Over 80 per cent of patients excrete The most common by products assayed -VMA and
HVA [homovanillic acid]
• Plain radiography shows fine, stippled calcification in 50 per cent of cases.
• Abdominal ultrasound examination shows the anatomical margins and extent of the disease.
• CT -demonstrates calcium in 80 per cent of cases and accurately evaluates intraspinal extension as well as hepatic and renal metastatic disease.
• MRI is - supersede CT in many patients. It will also evaluate bone marrow metastases.
• Meta-iodobenzyl-guanidine (MIBG, ] is metabolised by neuroblastoma cells -used for imaging--especially in small residual tumours not evident on other conventional imaging studies.
• Bone-seeking isotope (technerium-99m)- bone involvement,
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NEUROBLASTOMA IMMAGING & STAGING
CT is the best imaging study for patients with neuroblastoma and should be performed to determine the extent of disease.
Useful nuclear medicine studies include a technetium bone scan and a 131I-MIBG scan.
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NEUROBLASTOMA -TREATMENTTreatment depends on the stage of disease. Stage I and II tumors can be resected. Most abdominal tumors involve major
vessels. Unresectable abdominal tumors; Biopsy-radiation or chemotherapy, Then syrgery [if possible] Radiation therapy is useful in : a-nodal disease b-infants with spinal cord compression. chemoresponsive. Well responsive
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NEUROBLASTOMA -TREATMENT• Surgical excision - mainstay of cure in
localised disease, disease confined to one side of the midline delayed treatment following control by chemo- and radiotherapy. • No role of surgery as primary treatment in case of widespread disease at presentation • Multi drug chemotherapy and radiotherapy
are instituted in advanced /widespread disease. • cure rare remains low with an • overall survival rare of 30—35 per cent. • Age has an important favourable influence on
prognosis — the younger the patient the better the prognosis, and children in the first year of life have a long-term survival rare of 70 per cent.
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• It owes its name to the presence of chromaffin granules.
• usually pinkin colour composed of large, differentiated, sympathetic gan glion cells and a few fibres, enclosed in a delicate capsule.
• soft, vascular tumour usually less than 5 cm in diameter but occasionally very much larger.
PHEOCHROMOCYTOMA
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• The ‘10 per cent tumour’ - 10 per cent are bilateral, malignant, extra-adrenal, multiple, familial and occur in children.
• 90 per cent of phaeochromocytoma arise in the adrenal medulla
• May be found anywhere along the paraganglionic system. The most common extra-adrenal site is the organ of Zuckerkandl at the aortic bifurcation and less common sires are the urinary bladder, renal hilum, chest and neck.
• Extra-adrenal tumours - incidence of malignancy of 25—40 per cent.
PHEOCHROMOCYTOMA
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• Both sexes, early adult life or middle age.
• Produces intermittently or continu ously, excess of adrenaline, and especially of nor-adrenaline: the ratio of the latter to the former often being as high as 20:1 causing hypertension which is either paroxysmal or persistent.
• The persistent hypertension indicates a late stage of the disease.
• 0.5per cent- 3 per cent of cases of hypertension
• All patients under 60 years of age who suffer from sustained arterial hypertension deserve routine tests to confirm or exclude a phaeochromocytoma.
• Untreated, it progresses to a fatal termination from cardiac dysrhythmia or cerebral haemorrhage.
• A component of MEN II.
PHEOCHROMOCYTOMA Clinical features
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PHEOCHROMOCYTOMAClinical features
• Sudden attacks of panic and anxiety-A typical complaint is that of fear — ‘I thought I was going to die’.
• The most common symptoms, in order of frequency, are: headache (55 per cent), palpitation, vomiting, swearing, dyspnoea, weakness and pallor — i.e. the symptoms of adrenal overdosage. The paroxysmal attack may vary from a few minutes to some hours. The blood pressure may be very high and hyperglycaemia present.
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PHEOCHROMOCYTOMAClinical features D/D Symptoms may be mistaken for:
Hyperthyroidism, Hypo calcaemia, An acute anxiety state, Paroxysmal atrial tachycardia Carcinoid syndrome. failure to think about phaeochromocytoma
is the main cause of delayed diagnosis
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PHEOCHROMOCYTOMAAssociated SyndromesTen percent of pheochromocytomas occur as part of
inherited conditions. Bilateral medullary pheochromocytomas components of multiple endocrine neoplasia (MEN) types IIA and IIB. May occur in families without other manifestations of
MEN syndromes. They occur in 25 percent of patients with von Hippel–
Lindau's disease and in 1 percent of patients with neurofibromatosis and von Recklinghausen's disease.
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PHEOCHROMOCYTOMADiagnostic tests The basis of the laboratory diagnosis is measurement of elevated catecholamines and metabolites in urine and
blood.• Urine studies. Confirmation of the diagnosis made by: measurement of free catecholamines, VMA Metadrenalines (metanephrines) in 24-hour collections Patients with phaeochrornocytoma usually excrete: free catecholamines in excess of 100 ag/24 hours, VMA in excess of 7 mg/24 hours metadrenalines in excess of 1.3 mg/24 hours. Laboratories vary in the reliance they place on these various
estimations; False-positive elevations of metadrenaline excretion in patients taking monoamine oxidase-inhihiting drugs in those who have recently had angiographic contrast studies.
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PHEOCHROMOCYTOMA IMAGING-Localization
• Ultrasonography• Computerised tomography method of choice for localisation with an accuracy of 90—95
per cent • Arterio graphy and selective venous sampling.-obsolete.• Radionuclide imaging. -, iodine-labelled MIBG
localisation of adrenal and ectopic phaeochromocytomas. Only abnormal areas of adrenergic tissue show uptake
of MIBG- normal adrenals do not visualise. MIBG scanning may be particularly valuable in locating an
ectopic phaeochromocytoma when CT shows normal adrenals
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PHAEOCHROMOCYTOMATreatment
Medical and surgical management of pheochromocytoma ---------- Mayo - described in the United States Crout et al 1960s, elucidated the biochemical pathways and diagnostic catecholamine studies, allowing diagnostic ability prior to exploration.2
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PHAEOCHROMOCYTOMAPreoperative preparation
• Catecholamine-secreting Tumours are a challenge • Hypovolaemic because of the contraction of the vascular
bed • Handling of the tumour raise catecholamine levels up to
600-fold .• Severe hypotension may follow removal of the
tumour.
• Preoperative preparation. Effective blockade of the effects of high circulating catecholamines has significantly reduced the operative mortality and is mandatory.
• The alpha-adrenergic blocking drug phenoxybenzamine in an initial dose of 20—40 mg/day is increased until hypertension is controlled and mild orthostatic hypotension induced.
Preparation takes 1—3 weeks.• Beta-blocking drug propranolol is added for 3~7 days
before operation to control tachycardia and arrythmias. • Extra fluids should be given iv.
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PHAEOCHROMOCYTOMAOperation
• During surgery, intravenous infusions of alpha- and beta-blocking drugs are - determined by the blood pressure, pulse rate and central venous pressure.
• Hazardous phases during the induction of anesthesia, positioning of the patient on the operating table, when the tumour is manipulated, immediately after removal of the tumour. Sodium nitroprusside, a direct peripheral
vasodilator• Multiplicity of tumours (intra- and extra-adrenal)
and the need to avoidexcessive tumour manipulation necessitate a generous transabdominal approach. The tumour should be manipulated as little as possible and the main adrenal vein ligated as a first step. Inadvertent rupture of the tumour should be avoided as this may result in local spread and recurrence of even apparently benign tumours.
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PHAEOCHROMOCYTOMAMALIGNANT PHEOCHROMOCYTOMA
Metastases may not develop for years. The basic principle is to resect
recurrences of metastases whenever possible and to treat hypertension with appropriate blockade.
Radiotherapy. Painful bony metastases
Chemotherapy with cyclophosphamide, vincristine, and dacarbazine has been beneficial.
Five-year survival is 36–60 percent.
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ADRENALECTOMY• Open Surgery• Adrenalectomy may be done using a
posterior approach through the bed of the twelfth rib
• laparoscopy - using a lateral approach. The laparoscopic approach is suited for small aldosteronomas or cortisol-secreting adenomas or hyperplastic adrenal glands.
It is not recommended for Phaeochromocytoma because need for tumor manipulation and because
the adrenal vein cannot be controlled early.
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