Pathology of the Endocrine System Flashcards
Definition: “Endocrine glands are collections of specialized cells that ________, _____ and ______ release their secretory products into the ____ stream, resulting in physiological effects on target cells distant from the glands.”
Definition: “Endocrine glands are collections of specialized cells that synthesize, store and directly release their secretory products into
the blood stream, resulting in physiological effects on target cells distant from the glands
“The endocrine system consists of a highly integrated and widely distributed group of organs that orchestrate a state of metabolic ___________ or _________, among various organs of the body”
“The endocrine system consists of a highly integrated and widely distributed group of organs that orchestrate a state of metabolic equilibrium or homeostasis, among various organs of the body”
What has to happen in order for an organ to be considered dysfunctional ?
- Something’s been added
- Something’s been taken away
- Something’s not made right
What could have been added?
Hi, Fin!
Cells:
Hyperplasia
Neoplasia
Inflammatory
Fluid
Intra/extracellular
What could have been taken away?
Cells:
Atrophy
Apoptosis
Necrosis
What could not have been made right?
Aplasia
Hypoplasia
Dysplasia
Nodular hyperplasia is characterized as?
____ to ______
Generally _____ nodules
____/________
_____ demarcated
Not _______
Look like ______ cells
One to multiple
Generally small nodules
Uni/bilateral
Well demarcated
Not encapsulated
Look like normal cells
Adenoma is characterized as?
A for #1 –> Solitary, unilateral, well at all!
Usually solitary and unilateral
Well demarcated encapsulated
Normal….ish (cells deviate from perfectly normal
arrangement but not by much)
Carcinoma is characterized as?
Usually solitary and unilateral/bilateral
Poorly demarcated not encapsulated
Benign vs Malignant more difficult in
endocrine tissues but have features of
malignancy
Name the three features of malignancy.
Size
Cell morphology
Invasion
How is size a feature of malignancy?
Carcinomas tend to be ________, more likely to be __________ than adenomas
No hard-and-fast size cutoff (varies
depending on ______ of organ)
Rapid growth can lead to _________ and _________
Carcinomas tend to be larger, more likely to be bilateral than adenomas
No hard-and-fast size cutoff (varies
depending on size of organ)
Rapid growth can lead to necrosis and hemorrhage
How is cell morphology a feature of malignancy?
Cells more pleomorphic
Mitotic figures present, can be atypical
Anisocytosis
Anisokaryosis
Bi or multinucleated cells Bizarre cells
How is invasion a feature of malignancy?
Proliferative lesions can be?
Whether functional or not, large lesions
can ?
destroy the rest of the gland
and cause deficiencies in hormones secreted
by other populations of cells
What are the secondary changes that can occur in a case of malignancy?
Destruction of pituitary gland with lack of stimulatory hormone
Hyperplasia
Functional pituitary tumor: ↑ACTH
Developmental disorders
Aplasia –> ____ formed
Hypoplasia –> formed but _____
Dysplasia –> formed ________
Developmental disorders
Aplasia –> never formed
Hypoplasia –> formed but small
Dysplasia –> formed incorrectly
In cases of acute inflammation, most cases are secondary to _________ disease (_______, _______) or _____ extension rather than ______ infection suppurative
Most cases secondary to systemic disease (endotoxemia, septicemia) or local extension rather than primary infection suppurative
In cases of chronic inflammation, most cases are secondary to _____ disease with _______- evading agents (____, ___) or ________ disease
(pyo)granulomatous lymphoplasmacytic
Most cases secondary to systemic disease with immune- evading agents (fungal, MB) or autoimmune disease (pyo)granulomatous lymphoplasmacytic
Adenohypophysis
GH, ACTH, TSH, FSH, LH
Neurohypophysis:
ADH, Oxytocin
Adrenal cortex:
Cortisol, Aldosterone
Adrenal medulla:
Epinephrine, Norepinephrine
Thyroid gland:
T4, T3, Calcitonin
Parathyroid:
PTH
Islets of Langerhans:
Insulin, Glucagon, Gastrin, others
What are the general manifestations of endocrine disease?
- Endocrine diseases are common in _____ animal practice
- Alopecia with ______ or ______ disease
- Weight loss with feline ________
- Seizures caused by _________
- Bone fracture with _______
- Endocrine diseases are common in small animal practice
- Alopecia with hypothyroidism or Cushing’s disease
- Weight loss with feline hyperthyroidism
- Seizures caused by hyperinsulinism
- Bone fracture with hyperparathyroidism
- The neurohypophysis is derived from the?
- The adenohypophysis is derived from the?
- The neurohypophysis is composed of the?
- The adenohypophysis is composed of the?
Pituitary embryology
The embryo, diencephalon, and the pharynx. The invagination of the ectoderm of the pharynx and the outpouching of the diencephalon. This forms the future neurohyposis derived from the diencephalon and the hypophyseal pouch (oropharynx epithelium) will form the future adenohyphophysis.
The adenohypophysis is composed of the pars distalis and pars intermedia. Outpouching of diencephalon you have the pars nervosa.
Development of the pituitary gland
- What is the major part of the adenohypophysis?
- What surrounds Raucci’s pouch? What does it also separate?
- The pars nervosa is a continuation of?
- What is the pars nervosa composed of?
- What type of cells make up the Pars distalis?
- Pars distlais = major part of adenohyposphis
- Pars intermedia surrounding the raucci’s pouch and separating the pars distalis from nervosa.
- Pars nervosa is a continuation of the hypothalamus.
- Nervosa is composed of axons from neurons of the hypothalamus.
- Pars distalis has multiple cell types that secrete the trophic hormones.
The pars distalis is the ________ portion and is composed of several endocrine cell populations that secrete _____ hormones. Endocrine cells are surrounded by abundant _______.
The pars distalis is the largest portion and is composed of several endocrine cell populations that secrete pituitary hormones. Endocrine cells are surrounded by abundant capillaries.
Pituitary function
- Name the three different cell types that are found in the pituitary gland.
- List the 3 different types of basophillic cells in the pituitary gland.
- List the 2 different types of acidophils cells in the pituitary gland.
- List the functions of chromophobe cells found in the pituitary gland.
- Basophils, chromophobes, acidophils.
- Corticotrophs = ACTH, Thyroidotrophs = TSH, Gonadotrophs = FSH, LH
- Somatotrophs = GH, Lactotrophs = prolactin
- Chromophobes contain few secretory granules, can secrete any of the hormones; stem cells.
- Name the condition below.
- This condition results in the failure of the _______ ectoderm to develop into hormone-secreting cells of the pars _______. An enlarged _____ replaces almost all of the pituitary gland; its contents may have a ________ look.
- What does this condition lead to?
- Cystic Rathke’s pouch
- This condition results in the failure of the oropharyngeal ectoderm to develop into hormone-secreting cells of the pars distalis. An enlarged cyst replaces almost all of the pituitary gland; its contents may have a gelatinous look.
- Pituitary dwarfism (juvenile panhypopituitarism). Common in GSF.
Affected 5-month-old pup with normal
littermate
Dwarf pups appear normal from birth until
approximately 2 months of age
Dwarf pup: stunted growth and partial
alopecia
Dwarf pups appear normal from birth until
approximately 2 months of age
5-month old German Shepherd dog with pituitary dwarfism.
Retention of puppy hair coat and areas of alopecia
- Name the condition pictured below.
- Describe what this condition can be.
- If large enough, what impact would this have on surrounding structures?
- Adenoma of the pars distalis
- It can be large/small, functional/nonfunctional. If functional it would secrete ACTH.
- Suppress the optic chiasm, the rest of the pituitary gland, and the hypothalamus
In cases of functional adenomas of the pars distalis, a commonly associated pathology is?
diffuse hypertrophy of adrenal cortices.
Additional Complication of Hyperadrenocorticism
Pulmonary Thrombosis
Hypercoagulable state:
Impaired fibrinolysis (↑ PAI)
↑ clotting factors
- What condition is pictured below?
- Is this tumor usually functional or non-functional? If so, what hormone does it commonly secrete?
- This condition mostly effects what part of the brain?
- Is this tumor capable of metastasis?
- Carcinoma of pars distalis
- Most are non-functional. If functional, secretes ACTH.
- Optic chiasm
- Rest of gland, hypothalamus, brain, extend into the bone
PPID
Associated pathology
Hirsutism
Laminitis
Result of failure to seasonally shed
The condition pictured below is an associated pathology of ________ and is called _________. This condition causes –> insulin ______ ________–> believed to be the cause of ________.
PPID, resistant hyperglycemia, laminitis
Pituitary pathology
Pituitary pathology
- Name the condition pictured below.
- Nonencapsulated, multiple, discrete
Seen in older animals
Histologically resembles ZG with lipid droplets
- Nodular cortical hyperplasia
- What condition is pictured below?
- Is this tumor functional or non-functional?
- Is this tumor well or poorly demarcated?
- Is it easy or difficult to distinguish this tumor grossly?
- A cortical adenoma
- Can be functional or non-functional
- This tumor is usually a well-demarcated single nodule.
- Can be difficult to distinguish grossly from a solitary hyperplastic nodule; histo shows it is encapsulated.
- Name this condition
- Most likely to invade?
- Cortical carcinoma
- Caudal vena cava
- Describe the color of the mass pictured below. Based on the color, what is the origin of this tumor?
- This tumor is made up of what type of cells? These cells originate from where? What is this condition called?
- What species is this condition most common in?
- Pale tan = cortex, red to brown is from the medulla.
- Red to brown nodule in the medulla.
- This is a tumor from the chromaffin cells called Pheochomocytoma. Chromaffin cells are from the neural crest.
- Common in dogs and ruminants.
What condition is pictured below?
Chronic production of catecholamines –> hypertension. This is a very common of a function pheochromocytoma.
Secondary to hypertension–> cardiac hypertrophy –> arteriosclerosis and widespread hypertrophy.
This paper discussed a common sequelae of Pheochromocytomas: cardiomyopathies. Please describe the pathology of this associated condition.
Chronic hypertension –> ventricular hypertrophy –> arrhythmia –> systemic hypertension –> heart murmurs
Very well known condition in dogs.
Both malignant pheochromocytoma and adrenocortical carcinoma will commonly invade the ?
Both malignant pheochromocytoma and adrenocortical carcinoma will commonly invade the caudal vena cava.
Hypoadrenocorticism (Addison’s disease)
Causes:
1) Idiopathic (_______ hypoadrenocorticism): ________ pathogenesis; likely _______ mediated destruction of _____ (________ _________)
2) Secondary hypoadrenocorticism
- Pituitary tumor (lack of _____ secretion)
- Iatrogenic: ____ discontinuation of ______ corticosteroid administration, or _____ with o,p”-DDD (______) for treatment of hyperadrenocorticism
Hypoadrenocorticism (Addison’s disease)
Causes:
1) Idiopathic (Primary hypoadrenocorticism): Unknown pathogenesis; likely immune mediated destruction of cortex (lymphocytic adrenalitis)
2) Secondary hypoadrenocorticism
- Pituitary tumor (lack of ACTH secretion)
- Iatrogenic: Acute discontinuation of chronic corticosteroid administration, or overdosage with o,p”-DDD (mitotane) for treatment of hyperadrenocorticism
- What condition is pictured below?
- This condition is secondary to ________/_______ (Waterhouse-Friderichsen) and can also be seen with _____ trauma and terminal _______ (such as a trapped horse or chased wild animal).
- Adrenal hemorrhage
- This condition is secondary to septicemia/endotoxemia (Waterhouse-Friderichsen) and can also be seen with birth trauma and terminal overexertion (such as a trapped horse or chased wild animal).
- What is the condition below?
- Most common microbes you may see here?
- Describe the morphological characteristics.
- Adrenalitis
- Common b/c the adrenal gland is a forgotten tissue for pathologists. They are small. In cases of systemic diseases, it is common to see lesions here since there is a high blood supply, etc.
- Toxo, Histo, Crypto, Cocci, herpes, any type of systemic infection.
- Hypermia, swollen, edematous.
- What condition is this?
- Is this a common condition?
- In one large study, the rate of involvement of the adrenal glands in metastatic neoplasia for the following species was?
- Dogs
- Cats
- Horses
- Cattle
- Metastatic tumor of the adrenal gland secondary to another condition. This is very common due to its high blood supply.
- E..g lymphoma, mammary carcinoma, hemangiosarcoma.
The thyroid can be missed sometimes because it looks like muscle and sits on the larynx.
The majority of the thyroid is composed of _______-secreting epithelial cells lining _______-filled follicles (______ cells).
Between the follicles, you have the C-cells that secrete ________.
- Many _______
Some species have _______ parathyroid gland embedded within the gland.
The thyroid can be missed sometimes because it looks like muscle and sits on the larynx.
The majority of the thyroid is composed of hormone-secreting epithelial cells lining colloid-filled follicles (follicular cells).
Between the follicles, you have the C-cells that secrete calcitonin.
- Many capillaries
Some species have internal parathyroid gland embedded within the gland.
Around pink = follicles.
Colloid = pink
Follicles vary in size
Bet. here and interstitium you have the C cells that we only ID by IHC.
Around pink = follicles.
Colloid = pink
Follicles vary in size
Bet. here and interstitium you have the C cells that we only ID by IHC.
- What condition is pictured below?
- This condition is commonly seen in animals of what age?
- Is this tumor functional or non-functional?
- Nodular hyperplasia and adenomas.
- Older animals.
- Usually functional except in cats.
- What condition is seen here?
- This condition is characterized by?
- What is a major finding on serum biochemistry?
- What is a pathology commonly associated with this condition?
- This condition should NOT be confused with?
- Thyroid hyperplasia caused by Feline hyperthyroidism
- Characterized by Weight loss, despite polyphagia
- High serum T4 and T3 concentrations; Function of thyroid hormones is to Increases basal metabolic rate in the body.
- Associated pathology: Left ventricular hypertrophy
- Don’t confuse with feline HCM
- Classically HCM is a genetic disease and usually affects young/adult middle age cats, usually male castrated cats. LVH of the hyperthyroidism affects older cats b/c tumor in thyroid or nodular hyperplasia of thyroid.
- What condition is pictured below?
- This condition is common in what species?
- Can this be palpated on physical exam?
- Often have central areas of ____ and _________, _____ surrounding structures and vessels. More likely to be ______ b/c of metastasis: 1/3 _____, 2/3 _____. Very common to see metastasis in _______ lymph nodes and ______.
- Follicular cell carcinomas
- Very common in dogs; usually benign in cats.
- Large enough to palpate on physical exam.
- Often have central areas of necrosis and hemorrhage, invasion surrounding structures and vessels. More likely to be bilateral: 1/3 mobile, 2/3 fixed. Very common to see metastasis in regional lymph nodes and lungs.
- What condition is pictured below?
- Thyroid tumors sometimes bypass the regional lymph nodes and go to the ____.
- Follicular cell carcinoma
- lungs
There can be ectopic thyroid tissue present anywhere along the ______ neck from the ___ to the ____ of the heart and even _____ the heart.
DDx for disease in base of the heart: Ectopic thyroid carcinoma, lymphoma, hemangiosarcoma, and one more that is seen later in lecture
There can be ectopic thyroid tissue present anywhere along the ventral neck from the chin to the base of the heart and even within the heart.
- What condition is seen here?
- Common in?
- Pathogenesis?
- Associated with multiple endocrine neoplasia syndrome, which is common in humans but not so much in animals. C-cell tumors can also be associated with bilateral pheochromo ,pituitary adneomas.
C-cell tumors that affect horses –> usually older horses and it is an incidental finding. It is not idiopathic.
- C-cell tumor (ultimobronchial)
- Common in ruminants and horses.
- In ruminants it affects bulls on high calcium diet. The c-cell reacts to lower calcium levels –> hyperplastic and can become neoplastic.
- What condition is seen here?
- Very common in what species?
- Pathogenesis: _______ inflammation of thyroid; _____ mediated, kind of auto-immune. ______ will destroy the thyroid gland (autoantibodies directed against ______ or TSH _______)
- What can be seen on histo?
- Hypothyroidism (lymphocytic thyroiditis)
- dogs
- Lymphocytic inflammation of thyroid; immune mediated, kind of auto-immune. Lymphocytes will destroy the thyroid gland.
- Multifocal to coalescing infiltrates of lymphocytes and plasma cells.
- What condition can be seen below?
- This condition commonly causes what disease seen in geriatric dogs?
- This condition is characterized by ________ loss of thyroid tissue with replacement of _____ tissue and minimal to no ________.
- Idiopathic thyroid atrophy
- Common cause of hypothyroidism that is not immune-mediated.
Affects geriatric species, specifically dogs. - This condition is characterized by progressive loss of thyroid tissue with replacement of adipose tissue and minimal to no inflammation.
Associated pathology of hypothyroidism Myxedema with _________ facial skin folds and _____ facial expression + thickening of usually the _____ arteries and narrowing of the lumen due to deposition of _____.
_______ in metabolic rate so there is decrease in mobilization of _____ –> accumulation of cholesterol in the blood vessel wall. Not very well known, but atherosclerosis is an ______ finding in dogs, which is different from humans because it is the most common cause of cardiac infarcts in cases of hypercholesterolemia. In dogs, they usually do not cause cardiac infarcts.
Associated pathology of hypothyroidism Myxedema with thickened facial skin folds and tragic facial expression + thickening of usually the coronary arteries and narrowing of the lumen due to deposition of cholesterol.
Decrease in metabolic rate so there is decrease in mobilization of FA –> accumulation of cholesterol in the blood vessel wall. Not very well known, but atherosclerosis is an incidental finding in dogs, which is different from humans because it is the most common cause of cardiac infarcts in cases of hypercholesterolemia. In dogs, they usually do not cause cardiac infarcts.
What condition is pictured here?
What is the pathogenesis?
Thyroid gland that is gray/white b/c of the lymphocytic infiltration –> destruction of thyroid gland and atherosclerosis in thyroid artery. This is due to decrease metabolism of fat –> hypercholesterolemia –> cholesterol deposited here –> atherosclerosis
- What condition is pictured below?
- This condition is a gross enlargement of ______ glands due to diffuse ________ or increased _____.
- The causes are?
- Dietary iodine ________
- Dietary iodine ________
- _________ compounds
- Genetic “________ goiter”
- Goiter
- This condition is a gross enlargement of thyroid glands due to diffuse hyperplasia or increased colloid.
- The causes are?
- Dietary iodine deficiency
- Dietary iodine excess
- Goitrogenic compounds
- Genetic “congenital goiter”
Another cause of goiter is when an animal consumes foods containing goitrogenic compounds that binds to ______, inhibiting ______ absorption by thyroid glands. Common ones: ?
Another cause of goiter is when an animal consumes foods containing goitrogenic compounds that binds to iodine, inhibiting iodine absorption by thyroid glands. Common ones: broccoli, cabbage, kale, cauliflower.
The parathyroid is attached to the thyroid. The anatomy ____ amongst species. This one pictured is from a _____. This species has ___ external and ____ internal.
Parathyroid is a classic endocrine organ. _____ of cells with multiple ____. Secretes ____ in response to reduced Ca++ in the blood.
The parathyroid is attached to the thyroid. The anatomy varies amongst species. This one pictured is from a dog. Dogs have two external and two internal.
Parathyroid is a classic endocrine organ. Clusters of cells with multiple capillaries. Secretes PTH in response to reduced Ca++ in the blood.
Describe parathyroid function
- What condition is pictured below?
- Is this a common condition?
- When this condition is functional, what hormone does it secrete?
- The difference between carcinoma and adenoma is ______ invasion, increased cellular ________, _____, and ______ and _______ invasion.
- Parathyroid carcninoma
- No!
- PTH
- The difference between carcinoma and adenoma is capsular invasion, increased cellular pleomorphism, mitoses, and vascular and local invasion.
- What is the condition pictured below? What is its alternative name?
- What is this caused by?
- What does this condition commonly cause?
- List the other conditions that cause hypercalcemia in dogs? Cats?
- Pseudohyperparathyroidism. This syndrome is also called humoral calcemia of malignancy.
- Caused by tumors tht secrete a substance closely related to PTH, PTHrP (p= peptide).
- Hypercalcemia in dogs and cats.
- In dogs, the most common one if lymphoma and apocrine gland carcinoma of the anal sac glands. Abscess or infection of the anal sac gland, epithoid gland adenoma (good prognosis). Anal sac gland is usually malignant. Another tumor? multiple myeloma (tumors from plasma cells)
- What condition is pictured below?
- This tumor is located _____ to or in the ________ or, it can be in the _____ mediastinum. Usually an ______ finding. Can enlarge and rupture and lead to inflammation. Just have to monitor the size.
- Parathyroid (Kursteiner’s) cyst
- This tumor is located close to or in the parathyroid or, it can be in the cranial mediastinum.
- Below is a histological image from what organ?
- What can be seen scattered throughout the exocrine tissue?
- _______ to _______ clusters of approximately 50-100 cells scattered among the acini of the _______ (insert organ name here). Exocrine cells have ______, ________ _______ granules. Islet cells have moderate amounts of _____ _______ to _________ cytoplasm.
- The pancreas
- Islets of Langerhans
- Circular to irregular clusters of approximately 50-100 cells scattered among the acini of the exocrine pancreas. Exocrine cells have bright, eosinophillic zymogen granules. Islet cells have moderate amounts of pale eosinophillic to amphophillic cytoplasm.
Label the histological image below
See below.
- What condition is pictured below?
- In what species, and in what situation, is this most common in?
- Describe the pathogenesis of this condition.
- Islet vacuolar regeneration
- Chronic type II diabetes in cats
- Islet cells are reduced in number and vacuolated. Develops due to long-term overstimulation d/t peripheral insulin resistance.
- What condition is pictured below?
- This condition is common in which species?
- Pancreatic necrosis
- Common in dogs and cats. Enlarged with areas of inflammation, hyperemia, fibrin, edema, areas of necrosis. This will destroy the exocrine and endocrine pancreas due to severity of the process. When this happens, if dog survives, animals may develop diabetes because acute pancreatic necrosis destroyed endocrine pancreas.
