Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Endocrine > Thyroid pathology > Flashcards

Thyroid pathology Flashcards

1
Q

Describe the path of descent the thyroid goes through in embryological developmment

A

Develops from invagination of pharyngeal epithelium.

Descends from the foramen caecum to the normal place at the thyroglossal duct.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Failure to descend in embryological development

A

Lingual thyroid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Excessive descent in embryological development

A

Located retrosternally in mediastinum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Parafollicular cells are also known as

A

C cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Histological appearance of parafollicular cells

A

Larger cells (than follicular cells) that have clear cytoplasm.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Where does TSH act on the thyroid?

A

Thyroid follicular epithelium.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Histological appearence of a colloid

A

Big pink circles (the biggest cells in the thyroid) surrounded by small follicular cells.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How would you distinguish between follicular cells and parafollicular cells on a histological slide?

A

Parafollicular cells have a clear cytoplasm whereas follicular cells stain pink/purple.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What issue in the pituitary can cause hyperthyroidism?

A

TSH secreting pituitary adenoma.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What pathology in the ovaries can cause hyperthyroidism?

A

Struma ovarii- rare tumour in the ovaries that is made up of thyroid tissue.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is thyrotoxicosis? What can cause thyrotoxicosis?

A

Excessive release of thyroid hormones (of any cause). Causes include graves, hyperfunctioning neoplasms e.g. adenomas and carcinomas.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Triad of features associated with graves disease

A

Hyperthyroidism with diffuse enlargement of the thyroid
Eye changes (exopthalmos)
Pretibial myxoedema.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How do autoantibodies cause damage to the thyroid in Hashimotors?

A

Anti-thyroglobulin and anti-peroxidase bind to the thyroid receptors and cause antibody dependent cell mediated toxicity.
CD8+ T cells mediate destruction of the thyroid epithelium.
T cell activation causes gamma interferon (cytokine) to be realised- recruiting macrophages to the site causing damage to the thyroid follicles.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Histological findings of Hashimotors disease?

A

Lymphoid follicles present within the thyroid gland.

Beginning to lose thyroid follicles.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Why does a reduction in T3 and T4 production cause goitre?

A

Reduction in levels of T3 and T4 mean that to compensate- levels of TSH increase. This stimulates gland enlargement.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Diffuse goitre

A

Enlargement of the whole thyroid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Nodular goitre

A

Enlargement of part of the thyroid.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Causes of diffuse goitre

A

Ingestion of substances that limit T4/T3 production.

Inborn errors of metabolism (dysmorphogenesis)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Causes of nodular goitre

A

Variation of response of follicular cells to external stimuli- mutation in the TSH signalling pathway
Rupture of follicles- could be due to heamorrhage, scarring, calcification.

20
Q

What types of neoplasms (new growths) can you get in the thyroid gland?

A

Benign- adenoma

Malignant- carcinoma

21
Q

Name the types of carcinoma that can present in the thyroid gland?

A 
Papillary carcinoma (75-80%)
Follicular carcinoma (10-20%
Medullary carcinoma (5%)
Anaplastic carcinoma (<5%)
22
Q

Name the type of adenoma that presents in the thyroid gland

A

Follicular adenoma

23
Q

Presentation of an adenoma on the thyroid?

A

Discrete solitary mass.
Encapsulated by a collagen cuff.
Made up of thyroid follicle cells.

24
Q

What can a follicular adenoma be difficult to distinguish from?

A

Follicular cell carcinoma or a dominant nodule in multinodular goitre.

25
Q

Genetic association of adenomas

A

Some patients have mutant ras or PIK3CA

Some patients have mutations in TSHR (thyroid stimulating hormone receptor) pathway.

26
Q

Who is most likely to be affected by carcinomas of the thyroid gland?

A

Female predominance

Predominantly occurs in early adulthood.

27
Q

What environmental factors are said to make you susceptible to thyroid carcinomas?

A

Ionising radiation to the neck

Iodine deficiency

28
Q

Presentation of papillary carcinoma

A

Usually solitary nodule in the thyroid. (however can be multifocal)
Often cystic
May be calcified.

29
Q

Characteristics of papillary carcinoma

A

Predisposed to having very early lymph node involvement. (different to follicular cell carcinoma because it spreads via blood)

30
Q

Typical presentation of papillary carcinoma in a patient

A

Patient comes in with nodule on neck. Moves when swallowing. Patient also has enlarged lymph node.

31
Q

Survival rate of papillary carcinoma

A

10 year survival is above 95%.

32
Q

Presentation of a follicular cell carcinoma

A

Generally a slow growing, painless, singular nodule.
It is non-functional.
May have surrounding capsule

33
Q

How do follicular cell carcinomas spread and to where would they go?

A

They spread via the blood. Generally to the bones, liver and lungs.
They won’t spread to the lymph nodes- good way to distinguish between them and papillary carcinomas.

34
Q

What differentiates a follicular cell adenoma from a follicular cell carcinoma?

A

For it to be a carcinoma you need capsular or vascular infiltration.
Also has more solid, and less follicular cell, architecture.

35
Q

Prognosis of follicular carcinoma

A

Dependent on level of invasion. If it is a high stage at presentation- 10 year survival is about 50%.
Minimally invasive lesions- 90% 10 year survival

36
Q

Medullary thyroid carcinoma (MTC) origin

A

Derived from C cells (also known as parafollicular cells).

37
Q

What do MTC’s secrete?

A

Calcitonin.

38
Q

What are MTCs associated with?

A

Associated with multiple endocrine neoplasia (types IIA or IIB) (multiple tumours in the endocrine system).
Familial medullary carcinoma.

39
Q

Most MTC cases are?

A

Sporadic (70%).

40
Q

Sporadic MTC cases present as

A

One solitary nodule

41
Q

Familial cases of MTC present as

A

Multicentric or bicentric.

42
Q

Histological description of MTC tumours

A

Composed of spindal or polygonal cells arranged in nests, trabeculae or follicles.
Calcitonin depositing.

43
Q

Describe the characteristics of MTCs

A

They are aggressive tumours. Sporadic cases will show a neck mass with local effects of dysphagia, hoarseness, airway compromise.

44
Q

Characteristics of anaplastic carcinomas

A

They are aggressive and rapidly growing tumours. They involve neck structures and are undifferentiated.

45
Q

Who is likely to get an anaplastic carcinoma

A

Older people

People who have had another sort of thyroid cancer.

Endocrine (20 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions