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How are the adenohypophysis and intermediate zone formed embryologically?
Between 3-6 weeks, Rathke's pouch arises as an in-folding of oral ectoderm that loses its connection to the early oral cavity
How does the adenohypophysis tissue appear in adults?
How is the neurohypophysis formed embryologically?
Between 3-6 weeks of development, the neuroectoderm from the diencephalon grows downward to meet Rathke's pouch
How does the neurohypophysis tissue appear in adults?
What is major structure is superior to the Pituitary Gland?
What structure is directly above the Pituitary Gland?
What structure is directly behind the Pituitary Gland?
What structure is directly in front of the Pituitary Gland?
Where is the Pituitary Gland located?
Embedded in the sphenoid bone in a little pouch known as the sella turcica
What is the Pituitary Gland surrounded by laterally?
the cavernous sinus
What type of deficits may be seen with pituitary enlargement?
- Cranial Nerve Deficits
- Facial pain, diplopia (double vision), ptosis
What artery is located close to the pituitary?
What two arteries are directly lateral to the pituitary and are a source of blood supply?
Internal Carotid Arteries
What connects the pituitary gland to the hypothalamus?
Infundibulum (pituitary stalk)
What type of axons make up the optic chiasm?
Describe the blood supply to the adenohypophysis?
- Main blood supply is the low pressure venous system: carries hypophysiotropic factors with it from hypothalamus to pituitary; anterior lobe hormones drain into hypophyseal veins and thus into the general circulation
- Hypophyseal brances of ICAs: indirect supply
What are the two systems within the Hypothalamohypophyseal System?
- Supraoptic/ Paraventricular --> magnocellular
- Median Eminence (Tuberoinfundibular) --> parvicellular
What hormones in the median eminence are under anterior pituitary control (stimulating)?
- TRH --> TSH
- CRH --> ACTH
- GnRH --> FSH, LH
- GHRH --> GH
What hormones are under inhibitory control within the median eminence?
- Dopamine --> PRL (prolactin)
- Somatostatin --> GH, TSH
Where do the following hormones secreted by the anterior pituitary, have effect?
- TSH: thyroid
- ACTH: adrenal gland
- FSH: follicle in ovary, spermatogenesis
- LH: ovulation, testosterone
- GH: affects tons of tissues
How is the Adenohypophysis described histologically?
Lobular configuration of tissue with cells arranged in nests and cords with fine vascular network
Where are acidophils located within the adenohypophysis, and what hormones are secreted here?
- Lateral Wings
- Somatotrophs (GH) & Lactotrophs (PRL)
Where are basophils located within the hypophysis, and what types of hormones do they secrete?
- Aggregate at midline of pituitary
- Corticotrophs (ACTH), Thyrotrophs (TSH), & Gonadotrophs (FSH, LH)
What type of hormones do Chromophobes secrete within the adenohypophysis?
- Gonadotrophs (FSH, LH)
- Non-secretory cells
What are the two systems within the Neurohypophysis?
- Supraoptic (SO)
- Paraventricular (PV)
Neurons of the supraoptic (SO) or paraventricular (PV) nuclei produce what two hormones, which then are transmitted via fiber tracts to the posterior pituitary?
- ADH (vasopressin)
What are the two functions of Oxytocin?
- "Milk let-down" Reflex
- Uterine Contractions
What is the function of Vasopressin/ADH?
Controls resorption of water in the collecting duct to facilitate urine concentration (prevents from peeing a lot)
Describe the blood supply to the Neurohypophysis
Receives blood from Internal Carotids only
What hormones are produced by the Neurohypophysis?
None -- posterior pituitary is a storage area only
How does the Neurohypophysis appear histologically?
Posterior lobe looks neural; the fibrillar appearance could be confused with a glial tumor
What are three pathologies commonly seen in the Pituitary?
- Hypersecretion (Hyperpituitarism)
- Hyposecretion (Hypopituitarism)
- Mass Effects
What are three possible causes of Hyperpituitarism?
- Hypothalamic Hypersecretion: rare
- Loss of Negative Feedback: normally, target gland hormones feedback to the hypothalamus-pituitary axis
- Autonomous Pituitary Secretion: most commonly due to functional pituitary adenomas
What is the most common cause of Hyperpituitarism, and what is the most common cause of this?
Autonomous Pituitary Secretion: most commonly due to functional pituitary adenomas
This type of pituitary adenoma, seen in 10% of the population, is described as an adenoma of < 1 cm in diameter. Therefore, this adenoma type cannot produce mass effects. If these are non-secreting and have no mass effect, there is no treatment necessary.
This type of pituitary adenoma can produce mass effects even if non-funcitonal. These are usually treated even if not secretory due to the possibility of mass effects.
Prolactin-producing cells in the normal gland are laterally placed and are both _______ and ________.
What tonically inhibits prolactin release?
What two things can lead to hyperprolacinemia?
- DA antagonists
- Physical damage to teh hypothalamus/stalk
What normally stimulates prolactin production? Keeping this in mind, what can lead to hyperprolactinemia?
- Hypothyroidism can lead to hyperprolactinemia
How do Prolactinomas typically present in women?
- Typically microadenomas
- Present with galactorrhoea, menstrual irregularity (amenorrhea), and infertility
How do Prolactinomas typically present in men?
- Typically macroadenomas
- Present with galactorrhoea, visual field abnormalities, headaches, and impotence
What is the most common type of pituitary adenoma?
What visual field deficit is commonly seen in Prolactinoma?
Bitemporal Hemianopsia due to compression of crossing fibers in the optic chiasm. Can't see lateral visual field
Normal somatotrophs (GH) are ________.
Secretion of GH is regulated by what two hormones?
GH has an indirect action on cells via what hepatic somatomedin?
What are some of the symptoms associated with Hypersomatotropism? How two hormones are involved?
- Symptoms: Prepubertal -- Giantism; Postpubertal -- Acromegaly (thick skin; enlarged hands, feet, jaws, forehead)
- Hormones: GH, PRL
What are the three metabolic effects associated with Hypersomatotropism?
- Glucose Intolerance
Corticotrophs are ________ in the central adenohypophysis. ACTH stimulates the production of ________ hormones.
Excess glucocorticoids lead to characteristic signs including what 7 features?
Excess glucocorticoids lead to charactistic signs including obesity, hypertension, DM, amenorrhea, hirsuitism, atrophy, and depression. When diagnosed clinically, what is this known as?
Excess glucocorticoids lead to characteristic signs including obesity, hypertension, DM, amenorrhea, hirsuitism, atrophy, and depession. When this arises from an ACTH-producing pituitary adenoma, what is it called?
Endogenous Cushing Syndrome is usually caused by what?
This is an adenoma hemorrhage and/or infarcts causing rapid expansion of the sella mass. Null cell adenomas are most prone to this phenomenon.
This syndrome has a varied presentation. Symptoms of hypothyroidism are seen, such as weight gain, cold intolerance, and fatigue. Symptoms of secondary adrenal failure can also be seen: nausea/vomiting, weakness, hypotension, and hyponatremia. In addition, decreased sex hormone production can also be seen, such as testicular atrophy and amenorrhea.
These are adenomas that grossly invade the dura or erode the sella turcica
This is very rare. A diagnosis requires metastatic tumor, spread in the CSF (cord, SA space), and brain invasion.
What is a suprasellar cause of hypopituitarism?
20% of all adenomas fall into this category. If clinically important, this is due to mass effects and there may be evidence of hypopituitarism.
Null Cell Adenomas
This most often results from postpartum pituitary necrosis. In this, pituitary hyperplasia during pregnancy induces a vascular vulnerability with prolonged/ excessive hemorrhage during/ after delivery. This can present with difficulties lactating in the postpartum period.
There is secondary necrosis of the pituitary tissue due to the weak blood supply combined with oxygen deprivation due to hemorrhage during delivery.
This is a syndrome resulting from herniation of leptomeninges through an enlarged sellar diaphragm. Compression of normal pituitary by arachnoid/CSF gives this syndrome the appearance responsible for its name. This is more common in obese, multiparous women.
"Empty Cell" Syndrome
Concerning Posterior Pituitary Syndromes, there are no real syndromes associated with Oxytocin. What are the syndromes associated with ADH?
- Excess: Syndrome of inappropriate ADH (SIADH): trauma, small cell CA; can lead to significant hyponatremia
- Deficiency: Diabetes Insipidous: can be central or peripheral and this impacts therapy with ADH analogues; hypernatremia
These are paired endocrine organs
What two things make up the Adrenal Cortex?
- Outer Cortex
- Inner Medulla
What is the Adrenal Cortex derived from embryologically?
Mesoderm of Urogenital Ridge
Where is the yellow-brown color of the Adrenal Cortex derived from?
Lipochrome pigments & lipid precursors (cholesterol & cholesterol esters) of steroid hormones
Normal adult adrenal glands are ____ to ____ grams each.
What effect does acute stress have on the adrenal glands?
What effect does prolonged stess have?
- 4-8 grams each
- Acute Stress: lipid depletion and reduction in weight
- Prolonged Stress: can induce hyperplasia of cortical cells and increase weight to more than twice normal
What are the three layers of the Adrenal Cortex?
- Zona Glomerulosa
- Zona Fasciculata
- Zona Reticularis
This layer of the adrenal cortex is subscapular and narrow. It is derived of clusters of cells with scant cytoplasm and few lipid droplets
This layer of the adrenal cortex is a broad middle layer. It comprises 75% of the total cortex. It is derived of columns of cells with clear cytoplasm containing lipid precursors
This layer of the adrenal cortex is narrow. It abuts the medulla, and is derived of clusters of more darkly staining cells with lipochrome pigments
What steroid hormone, secreted by the zona glomerulosa, promotes reabsorption of sodium (and water) and excretion of potassium?
Minaralocorticoid secretion is regulated primarily by serum ________ levels and ______-________-system (no significant response to ACTH under normal conditions)
The secretion of cortisol and sex steroids is regulated by what molecule?
What stimulates pituitary corticotrophs to secrete ACTH?
Hypothalamic CRH (corticotrophin releasing hormone)
This dysfunction of the Adrenal Cortex is characterized by cortical hyperplasia, cortical adenomas, and cortical carcinoma.
This defect, seen in Adrenocortical Hyperfunction, is usually the result of pituitary hypersecretion of ACTH. It may also occur with secretion of ectopic ACTH by a nonendocrine neoplasm. It is bilateral (endogenous stimulation); and has multiple hyperplastic cortical nodules.
This defect, seen in Adrenocortical Hyperfunction, is relatively common, and results in a yellow-orange nodule of variable size. It is usually less than 30 grams, and can be functional (produces aldosterone, cortisol, or sex steroids) or non-functional. Most are nonfunctional and may not be detected clinically.
This defect, seen in Adrenocortical Hyperfunction, is rare. It is highly malignant, and associated with a poor prognosis. Most are functional, and are usually large and infiltrative at the time of diagnosis.
What are the two diseases of the Adrenal Cortex?
- Adrenocortical Hyperfunction
- Adrenocortical Hypofunction
This type of hypercortisolism is caused by low serum ACTH
This type of hypercortisolism is caused by high serum ACTH
What effect does increased cortisol production have on pituitary ACTH?
What accounts for the majority (70%) of cases of endogenous hypercortisolism?
Pituitary Cushing Syndrome
This type of Cushing Syndrome is associated with a cortisol-secreting cortical neoplasm or bilateral nodular hyperplasia. If it is caused by a neoplasm, the contralateral adrenal becomes arrophic. This is a type of primary hypercortisolism.
Adrenal Cushing Syndrome
What are the two types of primary hypercortisolisms?
ACTH-Independent Cushing Syndrome
In this type of Cushing Syndrome, the adrenals function autonomously to produce excess cortisol independent of pituitary ACTH. The increased cortisol leads to decreased pituitary ACTH.
Cortisol levels do not decrease with dexamethasone (synthetic glucocorticoid which normally suppresses pituitary ACTH)
ACTH-Independent Cushing Syndrome
This type of Cushing Syndrome is associated with bilateral diffuse or nodular adrenal cortical hyperplasia.
Cortisol levels decrease with dexamethasone (synthetic glucocorticoid which suppresses pituitary ACTH)
Pituitary Cushing Syndrome
What are the two types of Secondary Hypercortisolisms?
- Pituitary Cushing Syndrome
- Paraneoplastic Cushing Syndrome
This type of Cushing Syndrome is due to secretion of ectopic ACTH by nonpituitary tumors, e.g. small cell carcinoma of lung or other neoplasms. The adrenal glands undergo bilateral cortical hyperplasia.
Cortisol levels do not decrease with dexamethasone (synthetic glucocorticoid which normally suppresses pituitary ACTH).
Adrenal enlargement is usually overshadowed by a rapid downhill course related to cancer.
Paraneoplastic Cushing Syndrome
This type of Cushing Syndrome is due to administration of exogenous glucocorticoids (anti-inflammatory Rx).
This is the most common cause of Cushing Syndrome.
It results in bilateral adrenal cortical atrophy (mostly zona fasciculata and zona reticularis) due to suppression of pituitary ACTH.
Iatrogenic Hypercortisolism is associated with _____ serum ACTH
What hormone serves to:
Promote fat deposition (face, neck, and trunk)
Induce gluconeogenesis & inhibit uptake of glucose by cells with resultant hyperglycemia, glucosuria, & polydipsia
Increase protein breakdown causing loss of collagen & bone resorption
Impair inflammatory response
What syndrome is associated with moon facies, buffalo hump, truncal obesity, abdominal striae, hirsutism, impaired glucose tolerance, proximal muscle weakness, osteoporosis, menstrual disorders, emotional lability, easy bruisability, and susceptibility to infection?
Adrenogenital or virilizing syndromes are due to excess _________.
What regulates adrenal androgen formation?
What two things can cause excess ACTH production?
- Adrenocortical Neoplasms (usually carcinomas)
- Congenital Adrenal Hyperplasia
This is a group of inherited metabolic errors each characterized by deficiency or lack of a particular enzyme in the biosynthesis of cortical steroids, particularly cortisol.
Steroidogenesis is channeled into other pathways, leading to increased androgens and virilization.
Congential Adrenal Hyperplasia
In Congenital Adrenal Hyperplasia, various metabolic errors all:
Block or partially block the production of _________ and shunt the steroid pathway toward _________ production.
Decrease the ___________ ___________ on the pituitary.
Increase serum _________.
Lead to bilateral cortical _________ and increased synthesis of __________.
- Cortisol; Androgen
- Feedback Inhibition
- Hyperplasia; Testosterone
A deficiency in what enzyme shunts the steroid pathway away from cortisol and toward androgen production? This is the most common cause of Congenital Adrenal Hyperplasia (90% of cases). The deficiency may range from partial to total.
Virilizing-21 Hydroxylase Deficiency
What does a Virilizing-21 Hydroxylase Deficiency cause in females? In males?
- Ambiguous Genitalia
- Precocious Puberty & Exaggerated Secondary Sex Characteristics
What does a total lack of Virilizing-21 Hydroxylase cause?
- Deficient cortisol synthesis
- Interferes with aldosteron production
- Salt wasting leads to hyponatremia and hyperkalemia
A deficiency in this enzyme shunts the steroid pathway away from cortisol and towards androgens. It also causes a buildup of an aldosterone precursor which is a potent mineralocorticoid.
This results in hypernatremia, hypokalemia, and hypertension.
Lack of 11-hydroxylase
Hyperaldosteronism is a chronic excess in mineralocorticoids due to excess aldosterone secretion. What two metabolic derangements does this cause?
- Sodium Retention (hypernatremia & hypertension)
- Potassium Secretion (hypokalemia, hypokalemic alkalosis, & increased urine potassium)
This is hyperaldosteronism due to autonomous overproduction of aldosterone with suppression of the renin-angiotensin system and decreased plasma renin activity. This may be related to an adrenocortical neoplasm (commonly an adenoma, rarely a carcinoma) or it may be related to an idiopathic bilateral adrenocortical hyperplasia
This is hyperaldosteronism due to activation of the renin-angiotensin system resulting in increased plasma renin. It is encountered in conditions related to: renal hypoperfusion (ischemia), arterial hypovolemia, renin producing tumors (e.g. some renal cell carcinomas).
Clinical manifestations include hypernatremia, hypokalemia, and high serum renin
What are the clinical manifestations associated with primary hyperaldosteronism?
- Hypernatremia: hypertension
- Hypokalemia: chronic fatigue, neuromuscular symptoms (weakness, rarely paralysis), and cardiac arrhythmias
- Decreased Renin production from kidney and LOW SERUM RENIN
This syndrome is most frequently seen in middle-aged females. It is usually caused by a solitary aldosterone-secreting adenoma <2 cm in size. The remainder of cases are associated with bilateral cortical hyperplasia.
Conn Syndrome (primary hyperaldosteronism)
Unlike cortical adenomas associated with Cushing Syndrome, aldosterone-secreting adenomas do not usually suppress ______ secretion. Therefore, the adjacent adrenal cortex and contralateral adrenal are not __________.
What are the clinical manifestations associated with secondary hyperaldosteronism?
- High Serum Renin
This may be caused by acute or chronic adrenocortical insufficiency, or by decreased stimulation of the adrenals due to deficiency of ACTH.
This form of Hypoadrenalism results from progressive destruction of the adrenal cortex. Clinical manifestations of insufficiency require compromise of at least 90% of adrenal cortex and significantly decreased levels of glucocorticoids and mineralocorticoids.
Clinical manifestations of this are insidious in onset, as there must be a significant decrease in glucocorticoids and mineralocorticoids. Progressive weakness and fatigue are seen, along with GI problems including anorexia, weight loss, N&V, diarrhea, hypotension, adn hyperpigmentation of skin.
Primary Chronic Adrenocortical Insufficiency -- Addison's Disease
What symptoms are associated with Addison Disease (primary chronic hypoadrenalism)?
- Progressive weakness & fatigue
- GI symptoms -- norexia, weight loss, N&V, diarrhea
- Hyperpigmentation of skin
- Volume Depletion
- Hypoglycemia (caused by decreased glucocorticoid levels)
What causes the hyperpigmentation of skin seen in Addison Disease (primary hypoadrenalism)?
Increased levels of ACTH precursor, pro-opiomelanocortin, that stimulates melanocytes
How is the diagnosis of Addison Disease (primary hypoadrenalism) made?
- Decreased serum and urine cortisol
- Lack of adrenal response to ACTH stimulation
More than 90% of cases of Addison Disease are attributed to what four disorders?
- Autoimmune Adrenalitis
- Metastatic Cancers
Autoimmune adrenalitis may be idiopathic and occur as an isolated disease, or it may occur in association with other autoimmune diseases as part of a sporadic or inherited clinical syndrome. Which accounts for the majority (60-70%) of cases?
The majority of patients with Addison Disease associated with autoimmune adrenalitis have autoantibodies to __________ _________ resulting in autoimmune destruction of steroidogenic cells and autoantibodies to key steroidogenic enzymes.
Autoimmune adrenalitis related Addison Disease may occur in association with other autoimmune diseases as part of a sporadic or inherited clinical syndrome. What are two such syndromes?
- Autoimmuo Polyendocrine Syndrome type I (APS1)
- Autoimmuo Polyendocrine Syndrome type II (APS2)
This form of Autoimmune related Addison Disease is characterized as:
autoimmune disease involving other organs
abnormalities of skin, dental enamel, and nails
? defect in T suppressor cell function
Autoimmune Polyendocrine Syndrome Type I (APS1)
This form of Autoimmune related Addison Disease is associated with:
autoimmune thyroid disease and/or insulin-dependent diabetes
associated with polymorphisms in HLA loci
Autoimmune Polyendocrine Syndrome Type II (APS2)
This form of hyopadrenalism is caused by decreased stimulation of adrenals due to ACTH deficiency associated with various disorders of hypothalamus or pituitary. These disorders may include cancer, infection, infarction, or irradiation involving hypothalamus or pituitary.
Secondary Hypoadrenalism -- Decreased Pituitary ACTH
In secondary Hypoadrenalism, the decreased ACTH secretion from the pituitary and decreased serum ACTH lead to:
- Decreased Cortisol and Androgens
- Normal or near normal Aldosterone Synthesis (no hyponatremia or hyperkalemia)
- Lacks cutaneous hyperpigmentation of primary Addison's because levels of ACTH percursor (pro-opiomelanocortin) are not elevated
How is secondary Hypoadrenalism diagnosed?
- Low serum ACTH
- Exogenous administration of ACTH leads to rise in serum cortisol
A primary acute adrenocortical insufficiency occurs in a variety of clinical settings: it can occur as a crisis in patients with chronic adrenocortical insufficiency precipitated by stress (trauma, infection, surgery, etc.). When this happens, the adrenal glands are incapable of responding with an increase in steroid output. This crisis may result in hypotension, shock, and vascular collapse. What is it called?
A primary acute adrenocortical insufficiency occurs in a variety of clinical settings: is can occur in patients maintained on exogenous corticosteroids. This may be precipitated by a rapid withdrawal of steroids or failure to increase steroid doses in response to acute stress. This in turn may precipitate a crisis as a result of an inability of atrophic adrenals to produce glucocorticoid hormones. What is this called?
A primary acute adrenocortical insufficiency occurs in a variety of clinical settings: it can occur as a result of a massive ___________ ___________. This may destroy the adrenal cortex as a result of: trauma (esp in newborns with prolonged & difficult labor), in patients maintained on anti-coagulant therpay, in postsurgical patients who develop disseminated intravascular coagulation (DIC), or as a complication of bacteremia.
This is an uncommon catastrophic syndrome that can occur at any age but is somewhat more common in children. It is comprised of an overwhelming bacterial infection due to Neissseria Meningitidis or other organisms. Patients develop DIC with widespread purpura, particularly of the skin. There is massive bilateral adrenal hemorrhage that leads to rapid adrenocortical insufficiency. The massive bilateral adrenal hemorrhage converts the glands to sacs of clotted blood. Patients develop rapidly progressive hypotension leading to shock. This is fatal if therapy is not instituted immediately -- death follows within hours to a few days.
These cells are present within the adrenal medulla, and other endocrine organs, and are widely dispersed. They may be derived from cells that migrated from the neural crest to endocrine glands during embryogenesis, from cells programmed by the neural crest, or from non-endocrine tissues during neoplastictransformation.
Tumors derived from ________ cells may present as mass lesions (nonfunctional) or may produce hormones or other substances with functional activity.
What endocrine disease is often associated with the thyroid gland? It is derived from parafollicular cells or neuroendocrine cells that secrete calcitonin. The neuroendocrine cells form nests, and acellular deposits of amyloid (derived from altered calcitonin polypeptides) may be present in adjacent stroma. This can occur sporadically, or in association with other endocrine neoplasms as part of Multiple Endocrine Neoplasia (MEN) Syndrome.
Medullary Carcinoma of the Thyroid
This is a group of genetically inherited diseases resulting in proliferative lesions (hyperplasias, adenomas, and carcinomas) of multiple endocrine organs.
Multiple Endocrine Neoplasia (MEN) Syndrome
This structure is embryologically, functionally, and structurally distinct from the adrenal cortex. It is composed of specialized neural crest (neuroendocrine) cells termed chromaffin cells. This is normally a major source of catecholamines, and also contains a variety of other bioactive amines and peptides.
The adrenal medulla is a major source of what hormones?
Catecholamines (norepinephrine and epinephrine)
The adrenal medulla is composed of two cell types derived from the neural crest. What are they? What are the two important neoplasm types associated with the adrenal medulla?
- Ganglion Cells & Pheochromocytes
- Neoplasms derived from Ganglion Cells (neuroblastic tumors) & Pheochromocytomas
This family of tumors are derived from embryonal neural crest cells. This is a common childhood tumor, most common in infants and children <5 (median age of diagnosis is 18 months). Most cases arise in the adrenal medulla or along the sympathetic ganglia in the abdomen or posterior mediastinum.
What is the typical presentation of a neuroblastoma?
- Generally present as abdominal mass, weight loss, malaise, fever in children < 2 yo.
- Older children may present with effects of metastases to bone, lung, or GI tract (e.g. bone pain, respiratory symptoms, GI problems)
What do most neuroblastomas secrete (90%)?
- There are elevated blood catecholamines and elevated urinary catecholamine metabolites
Are patients with neuroblastomas typically hypertensive?
How is a laboratory diagnosis of Neuroblastoma made?
Elevated metabolic catecholamine by-products in urine: metanephrine, normetanephrine, vanillylmandelic acid (VMA), homovanilic acid (HVA)
Grossly, this is usually large, soft, gray, and relatively well circumscribed. It has areas of hemorrhage, necrosis, and cystic change often present. It may invade adjacent structures (kidneys, renal vein, vena cava).
Histologically, it has "small, blue, round cell tumors" along with Homer-Wright Rosettes.
What are the two neuroblastomas that demonstrate potential for spontaneous or therapy-induced differentiation of primitive neuroblasts into mature elements? (spontaneous tumor regression is rarely reported in infants)
What is the typical course for neuroblastomas in children <2? In older children?
- Tumors remain localized and are amenable to complete resection
- Tumors are often unresectable and may present with widespread metastases (liver, lung, and bone marrow are common sites)
What is the prognosis of neuroblastomas dependent on?
- Age & Stage
- Children < 18 mo have excellent prognosis regardless of stage
- Children > 5 yr have guarded prognosis regardless of stage
This is a tumor that is composed of adrenal medullary cells that synthesize & release catecholamines. Patients often present with hypertension (dominant clinical manifestation in 90% of pts).
Patients with this tumor type commonly demonstrate chronic sustained elevation in BP punctuated by paroxysmal episodes of an abrupt increase in BP associated with tachycardia, palpitations, headache, sweating, tremor, and anxiety. Cardiac complications may include congestive heart failure, pulmonary edema, myocardial infarction, and cerebrovascular accidents
How are Pheochromocytomas diagnosed?
Elevated urinary catecholamine metabolites: vanillylmandelic acid (VMA) & metanephrine
What is the clinical significance of Pheochromocytomas?
They are a surgically correctable form of hypertension
What is the "10% tumor"?
10% of sporadic adrenal ones are bilateral in adrenal glands
10% biologically malignant
10% familial -- inherited as AD disease or in association with MEN syndrome
Histologically, these are arranged in well-defined (Zellballen) with a rich vascular network.