Brainscape's Knowledge GenomeTM

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


See full index

MBBS VI - SpC - Medicine > Endocrine - Thyroid mass > Flashcards

Endocrine - Thyroid mass Flashcards

1
Q

List all ddx of goitre

A

1) Simple goiter (endemic or sporadic) (70%)
- Diffuse
- Nodular

2) Neoplastic goiter (25%)
- Benign
- Malignant

3) Toxic goiter
- Diffuse toxic (Grave’s)
- Nodular toxic (Plummer’s)
- Toxic/ Functional adenoma

4) Thyroiditis
- Bacterial/ suppurative (acute)
- Viral (subacute)
- Lymphocytic/ Autoimmune (chronic)

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

List major histological types of thyroid carcinoma

A

1) Thyroid follicular epithelium-derived
a) Differentiated tumour:
o Papillary carcinoma (80 -90%)
o Follicular carcinoma (5 – 10%)
b) Undifferentiated tumour: Anaplastic carcinoma (5 – 10%)

2) Parafollicular cells (C-cells)-derived (produces calcitonin) Neuroendocrine tumour
o Medullary carcinoma (< 10%)

3) Other malignancy
• Lymphoma (1 – 2%)
• Sarcoma
• Metastatic cancer

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

Define simple goiter

List 5 histological subtypes

A

Any thyroid enlargement
Not due to neoplasia or inflammation
No thyroid dysfunction
Can be uninodular or multinodular

Colloid 
Haemorrhagic cystic 
Complex 
Hyperplastic 
Adenomatous

Adenomatous, hyperplastic, colloid polyps are multifocal

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

2 most common differentiated thyroid carcinoma

A 
Papillary CA (75%)
Follicular CA (10%)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Papillary CA

  • Specific risk factors
  • Cell origin
  • Histology
  • Number of nodules
  • Route of spread
A

RF: Radiation exposure, FAP, Gardner’s syndrome

Origin: Thyroid follicular epithelium, differentiated tumor

Histology: Orphan Annie eye nuclei, nuclear pseudoinclusions, papillary architecture, Psammoma bodies (microcalcs on USG),
tall cell variant (a/w poorer prognosis)

Number: Multifocal, Unilateral

Spread: Local or Lymphatics (Level VI LN first), hematogenous rarely

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

Follicular CA

  • Specific risk factors
  • Cell origin
  • Histology
  • Number of nodules
  • Route of spread
A

RF: Multinodular goitre

Cell: Thyroid follicular epithelium, differentiated tumor

Histology: capsular/vascular invasion cf follicular adenoma, Hurthle cell variant (a/w poorer prx)

Number: Solitary, Unilateral

Spread: haematogenous predilection
→ liver, lung, bone, brain

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

6 “P” Mnemonic for papillary CA of thyroid

A 
Popular (most common)
Palpable LNs
Positive 131I uptake
Positive prognosis
Post-op 131I to guide treatment
Psammoma bodies
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

4 “F” Mnemonic for Follicular CA of thyroid

A

Female predilection (3:1)
Far away metastasis (lungs, bones)
FNAC cannot diagnose
Favourable prognosis

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

Medullary CA

  • Cell origin
  • Specific Marker
  • Specific risk factor
  • Number of nodules
  • Mode of spread
  • Histology
A

Cell: Parafollicular cell (C-cell) derived, neuroendocrine tumor

Marker: CALCITONIN + CEA

RF: MEN2 syndrome, Familial MTC

Number: Multifocal, bilateral

Mode: Local, Lymphatics (70%)

Histology: Acellular amyloid deposit, multicentric C-cell hyperplasia

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

Anaplastic CA

  • Cell origin
  • Specific RF
  • Number of nodules
  • Spread
  • Histological features
A

Cell: thyroid follicular epithelium, Undifferentiated tumor

RF: Previous differentiated thyroid carcinoma

Number: Solitary, Unilateral

Spread: Local (main), hematogenous, lymphatic

Histological: Small blue round anaplastic cells

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

S/S of thyroid cancer

A

Thyroid nodule and neck swelling - Discomfort mainly (pain due to sudden increased mass in inflammation or hemorrhage)

Thyroid dysfunction - Hyper- or hypothyroidism

Local pressure symptoms - Dysphagia/ choking/ aspiration; SOB/ cough/ sputum; Hoarseness/ vocal cord paralysis/ stridor

SVC obstruction - retrosternal extension

Cervical lymphadenopathy

Distant metastatic symptoms (e.g. pleural effusion, neurological signs, bone pain…etc)

Constitutional symptoms

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

List 4 risk stratification systems for thyroid CA

A

TNM staging: predicts disease-specific mortality

MACIS system: predicts disease-specific mortality

AMES risk stratification: predicts disease-specific mortality
→ Age >45y, Metastasis, Extrathyroid extension, Size >4cm

ATA risk stratification: predicts disease recurrence risk

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

Outline investigations for thyroid nodule: biochemical, radiological and histological

A
  1. Biochemical:
    - CBC with differentials
    - Serum Ca and PO4
    - TFT: Serum TSH and fT3, fT4
    - Thyroid autoantibodies: Anti-thyroglobulin (recurrence after total resection)
    - Serum thyroglobulin (marker for differentiated tumor)
    - Serum calcitonin (marker for differentiated tumor, medullary carcinoma)
    - Serum CEA (marker for differentiated tumor, medullar carcinoma)
    - Genetic test: RET mutation in MEN2, TSH receptor mRNA RT-PCR
  2. Radiological:
    - Ultrasound of neck
    - FNAC
    - Thyroid Radioscintigraphy
    - CXR: Tracheal deviation, retrosternal extention
    - CT thorax: retrosternal extension, local invasion
    - Bronchoscopy and OGD: upper aerodigestive tract invasion
    - PET/CT, CT/MRI for distant metastasis
  3. Histological:
    Thyroidectomy for biopsy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Thyroid mass characteristics that suggest malignancy

A

Mass factors:

  • Solitary or multiple nodules (solitary more likely malignant)
  • Nodule characteristics (size, consistency, fixation)
  • Cervical LN enlargement
  • RLN palsy
  • Distant metastatic symptoms (e.g. pleural effusion, bone pain…etc)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Ultrasound evaluation of thyroid mass

  • Mode
  • Advantage
  • Disadvantage
  • Indication
A

Mode: B-mode real-time scanner at 10mHz probe

Advantage:

  • Non-invasive
  • No radiation
  • Convenient and cheap

Disadvantage:

  • High sensitivity but low specificity, cannot confirm Dx
  • Operator dependent

Indication:

  • All patients with goiter/ palpable nodule
  • Guide needle aspiration
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Patient risk factors of malignant thyroid mass

A

Female sex

Middle age

Family history: Thyroid cancer, FAP (Papillary carcinoma), MEN2 (medullary carcinoma), Gardner’s syndrome

Head and neck irradiation: childhood leukaemia, bone marrow transplant, environmental radiation

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

Outline T staging of TNM staging for thyroid cancer (AJCC UICC)

A

TX: Primary tumour cannot be assessed
T0: No evidence of primary tumour

T1: ≤ 2 cm in greatest dimension limited to thyroid

T2: > 2 cm but ≤ 4 cm in greatest dimension limited to thyroid

T3: > 4 cm in greatest dimension limited to thyroid OR gross extrathyroid extension invading only strap muscles

T4: gross extrathyroidal extension to subcutaneous soft tissues, larynx, trachea, esophagus, or recurrent laryngeal nerve; prevertebral fascia or encases carotid artery or mediastinal vessels

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

Outline the N and M staging of TNM staging for thyroid cancer

A

N0 - No met/ histologically confirmed benign LN

N1 - Regional LN metastasis to Level VI or VII; metastasis to Level I-V; metastasis to retropharyngeal LN

M0 - No distant met.
M1 - Distant met. present

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

Ddx midline neck mass

A 
 Thyroid nodule (isthmus)
 Thyroglossal cyst
 Dermoid cyst
 Ranula
 Level I lymph node
20
Q

Ddx anterior neck mass

A

Cysts and nodules:
 Thyroid nodules, thyroglossal cyst
 Branchial cleft cyst
 Laryngocele

Carotid artery:
 Carotid body tumour (Chemodectoma)
 Carotid artery aneurysm

 Submandibular gland mass

 Level II – IV lymph node enlargement

21
Q

Ddx posterior neck mass

A

 Schwannoma
 Cystic hygroma
 Cervical rib
 Level V lymph node (from NPC)

22
Q

Ddx supraclavicular neck mass

A

Supraclavicular lymph node

• Malignancy metastasize from below the clavicle such as gastrointestinal, lung and gynaecological sources

23
Q

Differentiate reactive, infective, lymphoma and malignant LN on P/E

A
  • Discrete, mobile, firm or rubbery but not rocky hard, slightly tender = Reactive LN
  • Isolated, asymmetric, tender, warm and erythematous, fluctuant = Infected LN
  • Firm, rubbery, rapidly expanding = Rapidly growing lymphoma
  • Rock-hard, fixed (invasion through capsule and fixed to underlying structures) and non-tender = Malignancy
24
Q

Ultrasound features of low-risk vs high-risk thyroid cancer

A
25
Q

Outline the Bethesda classification for thyroid mass

A
26
Q

Indications for performing FNAC after US exam of thyroid mass

A
27
Q

Why is core needle biopsy of thyroid mass not performed?

A

Core needle biopsy is NOT performed
o Lead to massive bleeding since thyroid is a very vascularized structure
o FNAC is very accurate in identifying type of thyroid cancer

28
Q

Indications of FNAC for thyroid mass Dx

A

Indications
o Sonographic criteria for FNA
o Hypofunctioning (cold) nodules in thyroid scintigraphy
o Dominant or atypical nodule in multinodular goitre
o Nodules associated with abnormal LN
o Complex or recurrent cystic nodules

29
Q

Thyroid scintigraphy

  • Function
  • Isotopes
  • Results (hot vs cold?)
  • Disadvantages
A

Function:
• Functional assessment of thyroid nodule
• Combined with LOW Serum TSH level indicates overt or subclinical hyperthyroidism which increases the possibility that a thyroid nodule is hyperfunctioning

Isotopes:
- IV radioisotope I-123 or Tc-99m

Results:

  • Hyperfunctioning (hot) nodules (uptake is greater than surrounding thyroid tissues) are rarely cancer and hence does NOT require FNA
  • Hypofunctioning (cold) nodules (uptake is less than surrounding thyroid tissues) has 10 – 20% of being cancer and hence requires FNA provided that sonographic criteria are met

Disadvantage:
Expensive, radiation, low specificity and sensitivity

30
Q

ATA guideline on USG evaluation and FNAC criteria for Thyroid mass

A
31
Q

Indications of surgery for benign thyroid nodules/ nodular goiter

A
  1. Pressure symptoms
  2. Rapid increasing size
  3. Retrosternal extension
  4. Suspected malignancy/ malignant potential
  5. Cosmetics and patient wish
32
Q

Surgical Treatment options for benign thyroid nodules (2)

Indication, risks, advantages

A

Hemithyroidectomy

  • Indication: uninodular goiter
  • Risks: Low chance of hypothyroidism, safe, minimal morbidities
  • Advantage: easy to re-operate on contralateral lobe in Completion Total Thyroidectomy

Bilateral Thyroidectomy

  • Indication: Multinodular goiter
  • Risks: Surgical risk, hypoparathyroidism, long-term thyroxine
  • Advantage: No recurrence
33
Q

Non-surgical treatment options for benign thyroid nodule

  • Types
  • Indication
  • Advantages and disadvantages
A

Types:

1) Ethanol injection (PEI)
2) HIFU
3) Radiofrequency ablation (RFA)
4) Percutaneous laser ablation (LA)
5) Microwave ablation (MWA)

Indications:
- Patient factors: symptomatic, single hyperfunctional nodule with growth, histologically benign on 2 FNAC

Advantage:
- Preserve function, minimal invasive, better cosmetics, no GA

Disadvantage:
- Fail to cure, regrowth, risk of ablation, expensive, long follow-up procedures

34
Q

Surgical Tx plan for Papillary CA of thyroid

A 
Hemithyroidectomy (1-4cm without extra-thyroidal extension)
Total thyroidectomy (>4cm with extra-thyroid extension and metastasis)

LN dissection:

  • Central compartment (Level VI) dissection as prophylaxis (high risk tumor) or therapeutic
  • Lateral compartment dissection for therapeutic removal
35
Q

Surgical Tx plan for Follicular thyroid CA

A

Hemithyroidectomy first after FNAC
Completion thyroidectomy for follicular carcinoma

LN dissection:

  • Central compartment (Level VI) dissection as prophylaxis (high risk tumor) or therapeutic
  • Lateral compartment dissection for therapeutic removal
36
Q

Surgical Tx plan for Medullary thyroid CA

A

ALL patients undergo Total Thyroidectomy (high risk, aggressive tumor, prone to metastasis)

LN dissection:

  • Central compartment (Level VI) dissection as prophylaxis for ALL patients
  • Lateral compartment dissection for therapeutic removal
37
Q

Surgical Tx plan for Anaplastic thyroid CA

A

Total thyroidectomy with post-operative chemotherapy/ combined chemo and radiotherapy

Chemotherapy or Radiotherapy with External Beam Radiotherapy (EBRT) for surgically inoperable tumor

Tracheostomy for upper airway obstruction

38
Q

Pre-operative preparation before thyroidectomy

A

 Anti-thyroid drugs or β-blockers
• Prevention of thyroid storm

 Calcium supplements and vitamin D
• Prevention of postoperative hypocalcemia
• Prevention of hungry bone syndrome (HBS)

 Lugol’s solution
• Block iodine uptake and secretion of thyroid hormone
• Decrease vascularity of thyroid gland to reduce intraoperative bleeding

39
Q

Compare total thyroidectomy vs hemithyroidectomy

  • Risk of recurrence
  • Risk of hypoparathyroidism
  • Risk of RLN palsy
A
40
Q

Compare post-op management plan after hemithyroidectomy vs total thyroidectomy

A

Total thyroidectomy needs:

  • RAI scan for recurrence
  • Adjuvant RAI ablation for residual tumor
  • Lifelong T4 replacement
  • Thyroglobulin monitoring for recurrence

None for hemithyroidectomy

41
Q

Outline 3 techniques of LN dissection for thyroid cancer

A
42
Q

Advantage and disadvantage of cervical LN dissection for thyroid cancer

A

Advantages:

  • Lower recurrence rate
  • Prevent mircometastasis

Disadvantage:

  • Detection of LN micrometastasis may lead to upstaging of disease
  • Risk of damaging parathyroid gland
  • Cosmetic: Lateral LN dissection require separate incision and scar
43
Q

Induction of radioactive Iodine uptake in thyroid cancer (check)

A

Thyroxine withdrawal for 4 weeks to induce hypothyroidism and increase TSH uptake

Give Thyrogen (synthetic TSH) 1-2 days before operation to increase radioactive iodine uptake

44
Q

Indication for post-operative radioactive Iodine

A

Stage I and II, Low risk tumor:

  • RAI for short-term ablation of occult microscopic tumor foci
  • Use for disease surveillance and recurrence

Stage III and IV, High risk tumor:

  • RAI for longer therapy to clear persistent/ residual tumor
  • RAI to clear nodal or distal metastasis
45
Q

Papillary thyroid microcarcinoma

  • Typical TNM stage
  • Risk
  • Prognosis
  • Treatment
A

Typical:
< 1cm and incidentally detected, Stage I

Risk: Extremely low, rare metastasis

Prognosis: Excellent survival

Treatment: Active observation after biopsy confirmation

MBBS VI - SpC - Medicine (80 decks)

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