Glands

Question 1

6. MRI of a mass in the parotid tail shows a well-circumscribed heterogeneous lesion with mixed cystic and enhancing solid components. Earlier US showed vessels in a hilar distribution with branches in the septa of the structure. There is no lymphadenopathy. What is the likely cause?

A. Warthin’s tumour

B. Ductal cyst

C. Lymphoepithelial cyst

D. Pseudoaneurysm from a branch of the external carotid artery

E. AVM

Answer 1

A. Warthin’s tumour

Warthin’s tumours are benign salivary gland tumours, accounting for 6-10% of all parotid tumours. Warthin’s tumours are bilateral in 15% of cases.

Question 2

34. A 40-year-old woman under investigation for hypoparathyroidism undergoes ultrasound of the neck. Which is the best answer regarding parathyroid adenoma?

A. Usually indistinguishable from margin of thyroid gland

B. High T1

C. Low T2

D. Typically hypoechoic nodules

E. Usually hypodense on CT

Answer 2

D. Typically hypoechoic nodules

Parathyroid adenomas are typically well circumscribed, round or oval hypoechoic nodules.

They are usually low signal on T1 and high on T2. However, they may appear as high signal on both in the presence of haemorrhagic change.

Parathyroid adenomas are usually hyperdense on CT.

Question 3

35. A 60-year-old with treated SCC of the orpharynx undergoes ultrasound neck to evaluate a new swelling. Which feature most likely indicates malignant nodes?

A. Matting

B. Calcification

C. Ovoid shape

D. Hilar vascularity

E. Peripheral vasculitis

Answer 3

E. Peripheral vasculitis

Matting is associated with tubercular lymph nodes. Increased peripheral vessels is a feature of malignant nodes.

Question 4

48. Which of the following is a case of increased radiotracer uptake in the thyroid gland?

A. Thyroid replacement therapy

B. Lithium therapy

C. Propylthiouracil

D. Chronic thyroidits

E. Radioiodine ablation

Answer 4

B. Lithium therapy

Other causes include early thyroiditis, hyperthyroidism, and rebound after withdrawal of anti-thyroid medications.

Question 5

@# 49. On a thyroid radioisotope study, which is a cause of a hot thyroid nodule?

A. Involutional nodule

B. Focal thyroiditis

C. Adenomatous hyperplasia

D. Granuloma

E. Abscess

Answer 5

C. Adenomatous hyperplasia

Other causes include autonomous adenoma and, very rarely, thyroid cancer. Any hot nodule on Tc-99m should be imaged with I-123 to differentiate between autonomous and cancerous lesions.

Question 6

@# 10) A 46-year-old patient presents with an enlarged level IV lymph node in the neck. Histology from FNA demonstrates metastatic squamous cell carcinoma. Which of the following is the most likely site of the primary malignancy?

a. oral cavity

b. nasopharynx

c. tongue

d. salivary gland

e. larynx

Answer 6

e. larynx

The lymph node chains in the neck are complex and consist of a superficial circular nodal group and a deep cervical chain.

Supraglottic laryngeal squamous cell carcinoma tends to spread to the high internal jugular vein chain of nodes, which are in level II, with tumours of the epiglottis, aryepiglottic folds and pyriform sinuses most likely to present with adenopathy.

This can be ipsilateral (most common), contralateral or bilateral.

Subglottic tumours tend to spread to bilateral middle- or lower-level nodes of the internal jugular vein chain in level III or IV.

The level IV lymph nodes also drain the hypopharynx, thyroid and upper oesophagus.

The oral cavity, including the tongue and nasopharynx, drains to the level II nodes.

The salivary glands drain to level I or II nodes.

Tumours confined to the vocal folds do not normally metastasize to lymph nodes.

Question 7

@# 26) A 43-year-old man presents with cough and numerous masses in the neck bilaterally. CT confirms multiple lymph nodes that enhance peripherally and contain areas of calcification. A cavitating lesion is noted in the right lung apex. What is the most likely diagnosis?

a. tuberculosis

b. metastatic laryngeal carcinoma

c. metastatic nasopharyngeal carcinoma

d. metastatic papillary thyroid carcinoma

e. metastatic squamous cell carcinoma of the lung

Answer 7

a. tuberculosis

Tuberculous lymphadenitis is the most common form of head and neck tuberculosis, representing 15% of all extrapulmonary tuberculous infections.

It is frequently bilateral and, the more inferior the involved nodes, the higher the prevalence of associated pulmonary disease.

Peripherally enhancing lymph nodes are seen with tuberculosis, metastatic disease (usually squamous cell tumours), lymphoma or infection.

The presence of calcification suggests tuberculosis, but it may also be seen with papillary or medullary thyroid carcinoma.

The other diagnoses listed may cause cervical lymphadenopathy, but the lung lesion would be unusual in all except a cavitating squamous cell carcinoma of the lung.

Question 8

(Ped) 26) A 7-year-old boy presents with a painless, 2 cm midline mass in the neck just below the hyoid bone. This moves superiorly on protrusion of tongue. US shows a cystic lesion. What is the most likely diagnosis?

a. branchial cleft cyst

b. ectopic thyroid

c. thyroglossal duct cyst

d. obstructed laryngocele

e. necrotic lymphadenopathy

Answer 8

c. thyroglossal duct cyst

Thyroglossal duct cyst is the commonest congenital neck mass. It presents as a painless midline neck lump, which moves superiorly on protruding the tongue.

Imaging shows a smooth cystic lesion, which may take up pertechnetate on nuclear medicine studies due to the presence of functioning thyroid tissue.

Ectopic thyroid is an important differential diagnosis, as this may be the only functioning thyroid tissue present and therefore should not be excised.

Laryngoceles and branchial cleft cysts present with masses to the side of the neck rather than in the midline.

Lymphadenopathy will usually present as solitary or multiple solid lumps in either side of the neck, but may be ‘cystic’ when necrotic.

Question 9

44) A 62-year-old male patient presents with a mass in the right side of his neck. CT shows an enlarged, right-sided lymph node anterior to sternocleidomastoid, below the level of the hyoid bone and above the cricoid ring. At which level does the node lie?

a. level I

b. level II

c. level III

d. level IV

e. level V

Answer 9

c. level III

Levels II, III and IV lie anterior to the sternocleidomastoid.

Level II is from base of skull to hyoid,

level III from hyoid to cricoid,

and level IV from cricoid to clavicle.

Level I is the submandibular space.

Level V is posterior to sternocleidomastoid.

Question 10

51) A patient presents with colicky, right-sided, abdominal pain and is found to have multiple renal calculi. Blood tests reveal hypercalcaemia and hyperparathyroidism. Ultrasound scan shows a hypoechoic nodule posterior to the left lobe of the thyroid suggestive of parathyroid adenoma. Which features on parathyroid scintigraphy, using pertechnetate and sestamibi (with delayed washout images), would suggest a functioning parathyroid adenoma at this site?

a. increased uptake on pertechnetate and sestamibi studies with delayed washout

b. no uptake on pertechnetate; increased uptake on sestamibi with normal washout

c. no uptake on pertechnetate; increased uptake on sestamibi with delayed washout

d. no uptake on pertechnetate or sestamibi studies including delayed image

e. increased uptake on pertechnetate and no uptake on sestamibi study including delayed image

Answer 10

c. no uptake on pertechnetate; increased uptake on sestamibi with delayed washout

Parathyroid adenomas do not take up pertechnetate, which is accumulated by thyroid tissue, whereas sestamibi is taken up by both thyroid and parathyroid tissue. Subtraction of these two images can then be used to show any difference that can be attributed to a parathyroid adenoma. The delayed image typically shows retention of sestamibi in parathyroid adenomas (delayed washout) compared with normal parathyroid and thyroid. Small parathyroid adenomas are often missed by scintigraphy.

Question 11

90) A 43-year-old female presents on an ultrasound list for a thyroid FNA. She has an enlarging thyroid gland, right lobe more so than the left, and is biochemically euthyroid. Ultrasound scan shows multiple solid nodules with some cystic areas and foci of calcification throughout both lobes and the isthmus, with no obvious dominant nodule. Regarding FNA, how should the radiologist proceed?

a. target solid lesion

b. target calcification

c. use multiple passes in both lobes

d. use single pass at multiple sites

e. do not perform FNA

Answer 11

e. do not perform FNA

The appearances are characteristic of a multinodular goitre, and FNA can be misleading in these cases. Imaging diagnosis alone is usually sufficient. If there is a dominant nodule that is clearly larger than the others or a solitary enlarging nodule found on follow-up, then FNA should be performed to exclude malignancy.

Question 12

4 A 45 year old female inpatient is sent to the US department for investigation of her goitre. Imaging reveals an enlarged thyroid gland with a lobulated outline. Multiple ill-defined hypoechoic areas are separated by echogenic septae. Blood results are unavailable.
What is the most likely diagnosis?

(a) Grave’s disease

(b) Hashimoto’s thyroiditis

(c) Multinodular goitre

(d) De Quervain’s thyroiditis

(e) Plummer’s disease

Answer 12

(b) Hashimoto’s thyroiditis

Hashimoto’s thyroiditis is the most common cause of goitrous hypothyroidism. Diagnosis is usually biased on serology rather than imaging. The appearances depend upon the stage of the disease: small avascular hypoechoic foci in the acute phase, followed by the chronic appearances described in the question and then by a small, end-stage, heterogeneous gland. None of the other conditions are associated with fibrous, echogenic septae.

Question 13

13 A patient was discovered to have elevated serum ionic calcium on routine blood tests, and was referred for further investigations. Which of the following appearances would be least consistent with a diagnosis of a parathyroid adenoma?

(a) A one centimetre hypoechoic mass posterior to the lower lobe of the left thyroid gland on US imaging

(b) A focus of increased uptake on 99mrc-sestamibi imaging

(c) An intensely enhancing nodule adjacent to the crico-thyroid junction on CT

(d) A high-signal lesion within the body of the thyroid gjand seen on T2W MR imaging

(e) A focus of increased tracer uptake on 99mrc-Pertechnetate Imaging

Answer 13

(e) A focus of increased tracer uptake on 99mrc-Pertechnetate Imaging

99mTc-Pertechnetate localises to the thyroid but not the parathyroid gland. This feature is exploited in combined studies where the 99mTc Pertechnetate scintigram is subtracted from a similarly acquired study using thallium-201 (which localises to both thyroid and parathyroid tissue).

Question 14

22 A thyroid nodule is found to be malignant. The tumour is 3 cm in size and limited to the gland. What is the local staging?

(a) T1

(b) T2

(c) T3

(d) T4

(e) TS

Answer 14

(b) T2

the staging is: Tl: tumour 2 cm or less, confined to the thyroid. T2: tumour > 2 cm but < 4 cm, confined to the thyroid. T3: tumour> 4 cm, limited to the thyroid; or any tumour with limited extension. T4: a) extension into the subcutaneous tissues, larynx, trachea, oesophagus or recurrent laryngeal nerve; b) extension into the prevertebral fascia or incases the carotid artery/ mediastinal vessels. There is no T5.

Question 15

28 Incidentally, an elderly man is found to have lesions in the tails of both parotid glands. These are sharply marginated with parenchymal inhomogeneity. There are thin-walled cystic components. The solid elements display only minimal enhancement. What is the most likely diagnosis in this asymptomatic patient?

(a) Mucoepidermoid carcinoma

(b) Pleomorphic adenoma

(c) Squamous cell carcinoma metastasis

(d) Warthin tumour

(e) Sjogren’s syndrome

Answer 15

(d) Warthin tumour

Although pleomorphic adenoma are the most common lesion, well circumscribed multiple/ bilateral parotid masses in an asymptomatic patient should be considered Warthin’s tumours.

Question 16

6 A patient presents with an enlarged, palpable cervical lymph node. Thyroid carcinoma is suspected, and an US is performed. What imaging feature would make a malignant node more likely?

(a) Short axis to long axis ratio (S/L) of 0.25

(b) Echogenic hilum

(c) Punctate calcification

(d) Central hilar flow pattern on colour doppler imaging

(e) Absence of visible subcapsular flow on colour doppler Imaging

Answer 16

(c) Punctate calcification

A number of features are suggestive of nodal metastases: a round, rather than elliptical shape (S/L axis ratio > 0.5), the absence of an echogenic hilum, a cystic area suggestive of necrosis, an ill-defined border, peripheral colour flow with regions of relative avascularity and subcapsular vessels, and punctate calcification (seen in metastases from papillary thyroid carcinoma).

Question 17

17 A patient presents with a lump thought to be arising from the thyroid gland. An US is arranged for further evaluation which confirms the solid lesion is thyroid in origin. Which imaging feature would be most suggestive of a malignant lesion?

(a) Cystic nature

(b) Complete low-echogenicity halo

(c) Comet tail artefact

(d) Coarse calcification

(e) Hypoechoic

Answer 17

(e) Hypoechoic

A number of features are suggestive of a benign, rather than malignant, lesion. Cystic lesions are usually benign; a comet tail artefact usually indicates a (benign) colloid cyst; a complete lowechogenicity ‘halo’ increases the odds of a benign lesion 12 times. The overall echogenicity is another indicator: 96% of hyperechoic lesions are benign, compared to 74% of isoechoic and 39% of hypoechoic lesions.

Question 18

30 A teenager presents with a small midline neck lump. On examination, the lump is noted to move superiorly upon protrusion of the tongue. Which of the following statements is incorrect regarding such lesions?

(a) They are characteristically suprahyoid

(b) Presentation with a painless mid line mass is common

(c) Can appear anechoic by US imaging

(d) Can appear uniformly echogenic by US imaging

(e) Can appear heterogeneous by US imaging

Answer 18

(a) They are characteristically suprahyoid

A thyroglossal duct cyst is described. Many are infrahyoid (25-60%), the US appearances can be extremely variable.

Question 19

@# 30. Regarding radionuclide imaging of thyroid cancers, which radiological finding best fits the diagnosis?

a. Usually concentrates radioiodine – follicular carcinoma

b. Usually concentrates pertechnetate – papillary carcinoma

c. Usually concentrates pertechnetate and radioiodine – papillary carcinoma

d. No radioiodine or pertechnetate uptake but frequently concentrates thallium-201 – medullary carcinoma

e. No radioiodine or pertechnetate uptake but frequently concentrates thallium-201 – anaplastic carcinoma

Answer 19

30. d. No radioiodine or pertechnetate uptake but frequently concentrates thallium-201 – medullary carcinoma

Types of thyroid carcinoma in order of worsening prognosis are papillary, follicular, medullary and anaplastic.

Papillary tumours usually concentrate radioiodine,

follicular tumours concentrate pertechnetate but fail to accumulate radioiodine,

and anaplastic tumours show no radioiodine uptake.

Question 20

35. A 48 year old woman presents with symptoms of hyperparathyroidism. Radionuclide and ultrasound imaging suggest the cause is a solitary parathyroid adenoma. The surgeon requests further localisation with MRI prior to surgery. Which imaging sequence and plane would you choose as the most sensitive for detection of the adenoma?

a. T1-weighted in the axial plane

b. T2-weighted in the coronal plane

c. FLAIR in the coronal plane

d. T2 fat-suppressed in the axial plane

e. Gradient-echo in the axial plane

Answer 20

35. d. T2 fat-suppressed in the axial plane

Question 21

37. A 50 year old woman presents with a palpable lump in her neck. Imaging demonstrates a malignant-looking mass in the thyroid gland. Which of the following findings would direct you towards a confident diagnosis?

a. Complex mass with areas of necrosis – papillary carcinoma

b. Calcified lymph nodes – medullary carcinoma

c. Osteosclerotic bone metastases – follicular carcinoma

d. Intratumoural calcifications – anaplastic carcinoma

e. Regional lymphadenopathy – anaplastic carcinoma

Answer 21

37. b. Calcified lymph nodes – medullary carcinoma

Lymph node calcification accompanied by a thyroid tumour is highly suggestive of medullary carcinoma. This tumour arises from parafollicular C-cells and can cause elevated calcitonin levels. The familial form of medullary carcinoma is associated with MEN II (parathyroid hyperplasia, phaeochromocytoma).
All four carcinomas may demonstrate calcification within the tumour and may also show various amounts of necrosis. Follicular carcinoma typically shows early haematogenous spread and metastases to bone are almost always osteolytic. Although rare, papillary carcinoma can also spread to bone and the lungs. Approximately 75% of anaplastic carcinomas have associated regional lymphadenopathy, however, papillary (40% but almost 90% in children) and medullary (50%) also show regional lymphatic spread.

Question 22

QUESTION 18
A 68-year-old man presents with left facial weakness and a craggy parotid mass. Investigations reveal a left parotid tumour which is found to be an adenoid cystic carcinoma following surgical resection. Which one of the following statements is true regarding adenoid cystic carcinoma affecting the salivary glands?

A It has a propensity for perineural spread.

B It is a rapidly growing tumour.

C It is also known as Warthin’s tumour.

D It is commonest in the parotid gland.

E It usually has the appearance of a multiloculated cyst on ultrasound.

Answer 22

A It has a propensity for perineural spread.

Question 23

QUESTION 26
A 52-year-old woman is referred for a neck ultrasound by her GP. She was found to be hypercalcaemic on recent routine blood tests. Which one of the following findings would support the presence of a parathyroid adenoma?

A A well-defined hyperechoic mass posterior to the thyroid gland

B A well-defined hypoechoic mass posterior to the thyroid gland

C A well-defined hyperechoic mass anterior to the thyroid gland

D An ill-defined hyperechoic mass anterior to the thyroid gland

E An ill-defined hypoechoic mass posterior to the thyroid gland

Answer 23

B A well-defined hypoechoic mass posterior to the thyroid gland

The typical appearance of a parathyroid adenoma is a well-defined oval hypoechoic or anechoic mass posterior to the thyroid gland.

Question 24

QUESTION 42
A 32-year-old woman with a known history of excessive alcohol intake presents with a lump on the left side of her neck. She has an ultrasound scan which demonstrates a solitary nodule of mixed reflectivity in the left lobe of her thyroid which measures 3 cm in diameter. She also has several enlarged, uniformly hypoechoic cervical lymph nodes. On thyroid scintigraphy a low uptake region is seen corresponding to the site of the nodule. What is the most likely diagnosis?

A Colloid nodule

B De Quervain’s thyroiditis

C Follicular carcinoma of thyroid

D Graves’ disease

E Papillary carcinoma of thyroid

Answer 24

E Papillary carcinoma of thyroid

Thyroid cancers tend to be cold on scintigraphy. Papillary carcinoma is the commonest thyroid tumour (50-80%) and spreads early to local lymph nodes.

Question 25

QUESTION 54
A 65-year-old woman sees her GP with diarrhoea, palpitations and fatigue. Clinical examination of her neck is normal, but her thyroid function tests are consistent with hyperthyroidism and she is referred for thyroid scintigraphy. Which one of the following statements is true regarding radionuclide thyroid imaging?

A Iodine 123 is taken up by the salivary glands.

B If iodine 123 is used, imaging should be performed immediately after the injection.

C If Tc-99m pertechnetate is used, imaging should be performed 4—6 hours after the injection.

D Increased uptake may be seen in the pyramidal lobe in normal individuals.

E It is contraindicated in patients with known parathyroid malignancy.

Answer 25

D Increased uptake may be seen in the pyramidal lobe in normal individuals.

Question 26

QUESTION 57
A 53-year-old woman is referred for an ultrasound by her GP as she has a lump in her right cheek which has grown slowly over a period of 8-10 months. Ultrasound demonstrates a multiloculated, predominantly hypoechoic mass in the right parotid gland. She goes on to have an MR1 which confirms a welldefined multiloculated mass. It is of low signal on Tlw images and high signal on T2w images. What is the most likely diagnosis?

A Adenoid cystic carcinoma

B Lipoma

C Lymphoma

D Pleomorphic adenoma

E Warthin’s tumour

Answer 26

D Pleomorphic adenoma

Question 27

QUESTION 62
A 38-year-old woman presents to her GP with constipation, tiredness and menorrhagia. On examination, she is found to have a goitre. A neck ultrasound reveals an enlarged thyroid gland with a diffusely heterogeneous echotexture. There is heterogeneous patchy uptake throughout the gland on thyroid scintigraphy. What is the most likely diagnosis?

A Graves’ disease

B Hashimoto’s thyroiditis

C Multifocal papillary thyroid cancer

D Subacute thyroiditis

E Toxic multinodular goitre

Answer 27

B Hashimoto’s thyroiditis

This is an autoimmune disorder which typically shows patchy, heterogeneous uptake on thyroid scintigraphy. The thyroid gland may be normal or enlarged at ultrasound in the acute stages although it may be fibrotic and ill-defined in end-stage disease.

Question 28

46. A 55-year-old man undergoes 99mTc scintigraphy on which incidental note is made of multiple foci of increased tracer uptake in the parotid regions. Ultrasound of the parotid glands demonstrates bilateral multiple hypoechoic lesions with anechoic areas. On MRI, the lesions are of intermediate signal intensity on T1WI and intermediate signal intensity with focal areas of hyperintensity on T2WI. There is no enhancement following contrast administration. What is the likely diagnosis?

A. Pleomorphic adenomas.

B. Warthin tumours.

C. Lipomas.

D. Haemangiomas.

E. Mucoepidermoid carcinomas

Answer 28

46. B. Warthin tumours.

Warthin tumour or adenolymphoma is the second most common benign tumour of the parotid gland. It is usually solitary. Multiple or bilateral parotid masses and increased uptake on 99mTc are strongly suggestive of Warthin tumour. Warthin tumours do not enhance following gadolinium administration. Pleomorphic adenomas are usually solitary and unilateral. They appear as hypoechoic, lobulated, well-defined lesions with posterior acoustic enhancement on ultrasound scan (USS). On MRI, they are of intermediate signal on T1WI and hyperintense on T2WI. They demonstrate homogenous enhancement following gadolinium administration. Mucoepidermoid carcinomas vary in appearances. Low-grade tumours are similar to pleomorphic adenomas. High-grade tumours are heterogenous with low to intermediate signal intensity on T1WI and T2WI. They demonstrate infiltrating margins and heterogenous enhancement following gadolinium administration

Question 29

(GU) 21. A 45-year-old male presents with severe epigastric pain radiating to the back. Blood tests reveal elevated serum amylase and calcium. A CT scan of abdomen demonstrates peripancreatic inflammatory stranding, renal medullary nephrocalcinosis, and sacro-iliac joint erosions. What further investigation(s) would you recommend?

A. Serum parathyroid hormone assay and 99mTc sestamibi scan.

B. Serum parathyroid hormone assay and 111In pentetreotide scan.

C. Serum parathyroid hormone assay and meta-iodobenzyl-guanidine (MIBG) scan.

D. Serum parathyroid hormone and 99mTc pertechnetate scan.

E. Serum parathyroid hormone assay and 201Tl scan.

Answer 29

21. A. Serum parathyroid hormone assay and 99mTc sestamibi scan.

Clinical findings, blood tests, and CT of the abdomen are diagnostic of pancreatitis. The most common causes for pancreatitis are alcohol and choledocholithiasis. Rarely, it may be caused by hyperparathyroidism. The associated findings on CT are suggestive of hyperparathyroidism, therefore further assessment with serum parathyroid hormone assay and 99mTc sestamibi scintigraphy is indicated. 99mTc sestamibi washes out more rapidly from the thyroid gland than from hyperfunctioning parathyroid glands and therefore it can be used on its own. MIBG, a noradrenaline analogue, is used in the evaluation of neuroblastomas and paragangliomas. 99mTc pertechnetate is taken up by the thyroid gland only and is therefore not useful on its own in parathyroid imaging. However, it can be used in combination with 201Tl, which is taken up by both thyroid and parathyroid. Subtracting the two scintigrams allows parathyroid localization.

Question 30

(GU) 26. A 50-year-old male with thyroid swelling undergoes ultrasound of the thyroid that shows a solitary hypoechoic nodule with punctate calcification and increased vascularity. An ultrasound guided fine needle aspiration is carried out and is reported as benign. What would you do next?

A. Repeat fine needle aspiration.

B. Follow-up ultrasound in 6 months.

C. No further follow-up.

D. Staging CT.

E. 99mTc sestamibi scan.

Answer 30

26. A. Repeat fine needle aspiration.

The features suspicious for malignancy on ultrasound are calcification, irregularity, solid lesion, and irregular halo- and hypervascularity. A repeat biopsy should be considered if there is discordance between imaging findings and cytology.

Question 31

(GU) 31. A 30-year-old male with a thyroid nodule is referred for an ultrasound guided FNA. The FNA cytology reveals medullary thyroid carcinoma, which is treated by total thyroidectomy. The following year he undergoes a CTPA examination, which shows a small nodule in the thyroid region. Which of the following serum markers is useful in assessing recurrence?
A. CA 19-9.

B. Calcitonin.

C. CA 125.

D. Thyroglobulin.

E. Calcium.

Answer 31

31. B. Calcitonin.

Medullary thyroid carcinoma arises from the parafollicular C cells of the thyroid that secrete calcitonin, therefore calcitonin is a useful tumour marker for medullary thyroid carcinoma. CEA is another tumour marker produced by neoplastic C cells. Thyroglobulin is produced by follicular cells and is therefore not useful in medullary carcinomas.

Question 32

(Ped) 66. A 14-year-old boy presents with a slow-growing painless mass at the angle of the mandible on the left. Ultrasound demonstrates a hypoechoic left parotid mass containing echogenic calcific foci. On follow-up contrastenhanced MRI, the mass demonstrates mild increased enhancement. Which of the following is the most likely diagnosis?

A. Warthin tumour.

B. Primary lymphoma.

C. Parotitis.

D. Pleomorphic adenoma.

E. Haemangioma.

Answer 32

66. D. Pleomorphic adenoma.

This is the most common benign salivary gland tumour in children and usually appears in later childhood or adolescence. The tumour originates in the parotid gland in up to 90% of cases. Haemangiomas are the next most common benign lesion. They are usually seen in the first 6 months of life and have a female predilection. They are hypoechoic and display a variable degree of abnormal vasculature. Parotitis is usually due to mumps and results in a tender gland, which is diffusely enlarged with a heterogenous echotexture on ultrasound. Warthin tumour is a well-circumscribed cystic solid lesion, usually towards the tail of the parotid gland. It is the most common lesion to manifest as multifocal or bilateral masses. Primary lymphoma of the salivary glands is rare, but most often involves the parotid. Ultrasound will show an enlarged, diffusely infiltrated gland.

Question 33

(GU) 71. A 54-year-old woman is noted to be hypercalcaemic after complaining of lethargy and abdominal pain. Subsequent biochemical testing reveals an elevated parathyroid hormone. She is referred for scintigraphy with 99mTc sestamibi. Which of the following radiological findings would suggest a diagnosis of parathyroid adenoma?

A. Focus of decreased radionuclide activity within the lower pole of the right lobe of thyroid on initial and delayed images.

B. Focus of decreased radionuclide activity within the lower pole of the right lobe of thyroid on delayed images only.

C. Focus of increased radionuclide activity within the lower pole of the right lobe of thyroid on initial and delayed images.

D. Focus of increased radionuclide activity within the lower pole of the right lobe of thyroid on initial images only.

E. Focus of increased radionuclide activity within the lower pole of the right lobe of thyroid on delayed images only

Answer 33

71. E. Focus of increased radionuclide activity within the lower pole of the right lobe of thyroid on delayed images only.

Solitary parathyroid adenoma accounts for 85% of cases of primary hyperparathyroidism, with parathyroid hyperplasia (10%), multiple adenomas (4%), and carcinoma (1%) making up the remainder. When 99mTc MIBI is used for parathyroid imaging, immediate and delayed images of the neck and mediastinum are performed. Parathyroid adenomas may or may not be visualized on initial imaging, but they retain radiopharmaceutical on delayed (1–2 hours) images, whereas the normal thyroid washes out.

Question 34

17 A 48-year-old man presents with a hard mass in the parotid gland. CT and MRI were performed and as a result of the radiological appearances a differential of mucoepidermoid carcinoma and adenoid cystic carcinoma was postulated. What characteristic radiological feature do they both exhibit?

a Ground-glass appearance on CT

b Hyperintense signal on both Ti- and T2-weighted images

C Signet ring enhancement post contrast

d Honeycombing on CT

e Perineural extension

Answer 34

17 Answer E. Perineural extension

The most common malignant tumour of the parotid gland is mucoepidermoid carcinoma and in children it is the most frequently occurring salivary gland malignancy. This tumour type is composed of both mucoid and squamous (epidermoid) cells, the latter forming the majority of the cell population in the more high-grade tumours. On both CT and MRI the imaging appearances can vary depending on the grade of the tumour, with low-grade lesions appearing well circumscribed while higher grade lesions are poorly defined and infiltrative. Signal intensities on both Ti- and T2-weighted images are low to intermediate, and enhancement is clearly evident post contrast. A hypointense signal intensity on T2W images enables differentiation between a parotid malignancy and a pleomorphic adenoma. Both adenocystic and mucoepidermoid tumours can exhibit perineural extension.

Question 35

23 A 55-year-old man with known squamous cell carcinoma of the larynx was noted to have some enlarged level II nodes on CT and an USS has been arranged. What feature on USS would make you most suspicious that they were enlarged due to infiltration with metastatic carcinoma?

a Orientated with long axis in axial plane

b Orientated with long axis orientated along cranio-caudal axis

c Round shape

d Reduced vascularity on Doppler imaging

e Prominent fatty hilum

Answer 35

23 Answer C: Round shape

Size alone is a relatively poor criterion in defining a neck lymph node to be possibly malignant. Oval nodes with a fatty hilum tend to be benign. The orientation of the node is irrelevant. Further features such as calcification, necrosis, extracapsular spread and increased Doppler flow could represent malignant spread.

Question 36

24 A 16-year-old girl with gradual onset of a swelling below her chin presents to the ENT surgeons. MR revealed a well-defined cystic lesion in the sublingual space with no septations or wall thickening. It was bright on T2 -weighted imaging and low signal on T1-weighted imaging. What is the most likely diagnosis?

a Ranula

b Second branchial cleft cyst

c Thyroglossal duct cyst

d Cystic hygroma

e Pleomorphic adenoma

Answer 36

24 Answer A: Ranula

These are the classical findings of a ranula. The most important differential diagnosis to exclude is a pleomorphic adenoma, which would enhance on fat saturated T1-weighted images. B would appear in the posterior triangle, while a thyroglossal duct cyst is likely to be in the midline. D is not normally sublingual and normally multiloculate

Question 37

(Ped) 33 A two-year-old girl, who is failing to thrive, presents with bilateral facial swelling that has increased in size recently. On palpation the swellings are firm and non-tender. The child undergoes an ultrasound. The parotid glands are seen to contain multiple anechoic areas without associated posterior enhancement. What is the most likely diagnosis?

a Mumps

b HIV parotitis

C Lymphadenitis

d Warthin’s tumour

e Branchial cleft cyst

Answer 37

33 Answer B: HIV parotitis

In HIV parotitis the swellings are chronic, firm and non-tender and are associated with an improved prognosis. In mumps the parotid swellings are tender. Warthin’s tumours are mixed solid/cystic lesions that usually present in adults.

Question 38

40 A 55-year-old woman who is hypothyroid with a large goitre undergoes a thyroid ultrasound, which demonstrates a diffusely enlarged thyroid with increased vascularity. She then undergoes a technetium-99m pertechnetate study. What findings would you expect to see?

a Homogeneous diffuse increase uptake

b Heterogeneous diffuse increase uptake

c Diffuse low uptake with a small nodule with increased uptake

d Diffuse low uptake

e Normal uptake

Answer 38

40 Answer D: Diffuse low uptake

This hypothyroid patient has Hashimoto’s disease. The ultrasound features of a heterogeneous diffusely enlarged low-reflectivity thyroid with increased vascularity are very typical of Hashimoto’s disease. On Tc-99m imaging there is generalised low uptake of tracer within the thyroid. The pyramidal lobe can be prominent and there may be a single or multiple cold nodule within the thyroid.

Question 39

23 This question relates to the descent of the thyroid gland during development. At which of the following anatomical sites are you least likely to find maldescended thyroid tissue?

a Within foramen lacerum

b Within foramen caecum

c Anterior to the thyroid cartilage

d Within the hyoid bone

e Anterior to the hyoid bone

Answer 39

23 Answer A: Within foramen lacerum

Answer A is incorrect as all the other answers are on the normal course of thyroid descent from the back of the tongue (foramen caecum) inferiorly to its normal position in the neck. Foramen lacerum transmits the internal carotid artery.

Question 40

38 A patient has a dual phase subtraction study for investigation of hyperparathyroidism and a focus of uptake is seen on the Tc-99m-mibi scan with a corresponding area of increased uptake on the 1123 study in the region of upper pole of the right lobe of the gland. What is the most likely cause for this finding?

a Functioning parathyroid adenoma

b Papillary thyroid tumour

C Multinodular goitre with prominent nodule

d Solitary functioning thyroid nodule

e Submandibular salivary gland

Answer 40

38 Answer C: Multinodular goitre with prominent nodule

Multinodular goitre can give rise to heterogeneous uptake in both types of scan as a functioning thyroid nodule will take up both tracers. The presence of smooth uniform uptake on the thyroid scan would have been more consistent with a functioning parathyroid adenoma. Salivary gland uptake is seen with Tc-99m pertechnetate but not I131. Thyroid malignancy presents as a cold (nonfunctioning) nodule in 90% of scans

Question 41

42 A female is referred from a thyroid clinic with suspected Graves’ disease with an elevated T3 and low TSH. She is a tachycardic at 90 bpm but has a regular pulse and has minor eye symptoms. She is booked for a technetium99m pertechnetate scan prior to any therapy. If the diagnosis is correct,what is the scan likely to show?

a Normal uptake

b Diffuse avid uptake in a uniform pattern

c Patchy appearance with areas of intense uptake

d Uniform reduced uptake throughout the gland

e A technetium scan is contraindicated due to the risk of thyroid storm

Answer 41

42 Answer B: Diffuse avid uptake in a uniform pattern

Graves’ disease usually shows avid uniform uptake. Patchy uptake may indicate Hashimoto’s thyroiditis or multiple hot nodules. Radioactive thyroid therapy is contraindicated in poorly controlled thyrotoxicosis as it may precipitate a thyroid storm and can worsen eye symptoms but a diagnostic scan is appropriate.

Question 42

10 A 24-year-old patient presented with a painless lump in the right submandibular region, which had been present for three years and had been gradually increasing in size, now measuring 1.5 cm. A FNA revealed features suggestive of a submandibular pleomorphic adenoma. What are the most likely imaging characteristics?

a Isointense to muscle on T1W MRI

b Hypointense to muscle on T2 W

C Poor enhancement post gadolinium

d A smooth margin

e Areas of calcification on CT

Answer 42

10 Answer A: Isointense to muscle on T1 W MRI

Pleomorphic adenomas are benign lesions containing both mesodermal and glandular tissue. They most commonly occur in the parotid gland but can also arise within the other minor salivary glands. On CT they are generally well demarcated, homogeneous and slightly hyperdense to muscle. Typically, there is no significant enhancement post contrast. On MRI they are isointense to muscle on Ti and become hyperintense on T2 -weighted images with avid enhancement post gadolinium. Adenomas of less than 0.5 cm tend to have a smooth margin while larger lesions may appear more lobulated. Eighty per cent of all pleomorphic tumours occur in the parotid gland and of these 80% occur in the superficial lobe.

Question 43

16 A 59-year-old lady is being investigated for hypercalcaemia after being referred with general malaise, weight loss and bone pain. A whole body bone scan demonstrates markedly increased and diffuse tracer uptake in the appendicular skeleton with increased bone to soft tissue ratio and absent renal uptake. Plain films show speckled soft-tissue calcification. An ultrasound of the neck shows a small low-reflectivity lesion posterior to the right lobe of the thyroid. What is the likely explanation for the bone scan appearances?

a Hyperparathyroidism secondary to parathyroid adenoma

b Widespread metastases with metastatic deposits in nodes in the neck

C Renal osteodystrophy

d Myeloproliferative disease

e Hyperthyroidism with a multinodular goiter

Answer 43

16 Answer A: Hyperparathyroidism secondary to parathyroid adenoma

This appearance is a `superscan’. Causes include widespread metastatic disease, renal osteodystrophy, osteomalacia, hyperparathyroidism, hyperthyroidism, myeloproliferative disorders, Waldenstrom’s macroglobulinaemia, mastocytosis and Paget’s disease. The probable parathyroid adenoma makes this the likely cause.

Question 44

20 A 58-year-old man presented with a two-year history of a painless palpable swelling in the region of his left parotid. On examination the mass was mobile and superficial to his facial nerve. Imaging with MR revealed a septated well-defined mass in the parotid tail. On T1-weighted sequences it was of low signal relative to the parotid gland and enhanced with contrast. On T2-weighted imaging the mass was of heterogeneously high signal. What is the most likely diagnosis?

a Warthin’s tumour

b Siladenitis

C Lipoma

d Mucoepidermoid carcinoma

e Sjogren’s syndrome

Answer 44

20 Answer A: Warthin’s tumour

The description given is typical of the imaging appearance. Siladenitis is usually caused by Streptococcus or Haernophilus infections and typically produces inflammatory change within the gland and subcutaneous tissue oedema. Sialectasia does occur. Mucoepidermoid cancers are poorly defined lesions lacking enhancement which and perineural spread may be visible particularly on T2- weighted images. Sjogren’s syndrome is commonly bilateral. The most common imaging feature is multiple small cysts in an enlarged parotid gland.

Question 45

40 A 25-year-old homosexual man went to a GUM clinic with penile warts. He reported having unprotected sex with multiple casual partners. An HIV test was positive and his CD4 count was 300. He complained of painless swelling of his parotid glands and a MRI was performed. What would you expect to see?

a Diffuse generalised enlargement of the parotid glands

b Multiple normal-sized lymph nodes

c Diffuse heterogeneous low signal with increase vascularity

d Multiple bilateral small cysts within both parotid glands

e Diffusely enlarged glands with microcalcification.

Answer 45

40 Answer D: Multiple bilateral small cysts within both parotid glands

Benign lymphoepithelial cysts are painless cystic swellings of the parotid gland seen in HIV positive patients. The condition is bilateral in 20% of patients. The cysts originate from lymph nodes within the parotid gland and are typically small, multiple and in the superficial lobes. They have the typical imaging features of cysts.

Question 46

(Ped) 68 A 14-day-old boy is admitted with prolonged jaundice and poor feeding. On examination he is hypotonic with cool, mottled skin, abdominal distension and an umbilical hernia. Serum biochemistry reveals a low T4 and an elevated TSH. Which of the following is the most likely ultrasound appearance?

a No thyroid tissue seen

b Ectopic thyroid tissue seen in the suprahyoid position

C Enlarged echogenic thyroid

d Solitary low reflectivity nodule within the thyroid

e Multiple low reflectivity nodules within an enlarged thyroid

Answer 46

68 Answer B: Ectopic thyroid tissue seen in the suprahyoid position

The condition described is congenital hypothyroidism. Ectopic thyroid is the most common cause of congenital hypothyroidism.

Question 47

2. A 30-year-old man presents with a lump in the left cheek. Ultrasound examination shows an 8 mm hypoechoic and lobulated lesion with a hyperechoic centre. The most likely cause of the lesion is?

(a) Parotid duct stone

(b) Lymph node

(c) Warthin’s tumour

(d) Pleomorphic adenoma

(e) Abscess

Answer 47

2. (b) Lymph node

Typical appearances of intraglandular lymph nodes are of a hypoechoic periphery with a fatty hyperechoic centre.

Question 48

12. A 70-year-old man with chronic rheumatoid arthritis presents with recurrent episodes of dry eyes, mouth and bilateral parotid swellings. CT shows bilateral diffuse parotid swellings with punctate calcifications and heterogenous contrast enhancement. MRI shows diffuse cystic lesions within both parotids on STIR. The most likely diagnosis is?

(a) Sjögren syndrome

(b) Non-Hodgkin’s lymphoma of the parotid glands

(c) Warthin’s tumours

(d) Metastatic disease

(e) Bilateral pleomorphic adenoma

Answer 48

12. (a) Sjögren syndrome

An autoimmune condition causing salivary and lacrimal gland destruction. The secondary type is commonly related to rheumatoid arthritis, presenting with recurrent dry eyes, mouth and skin and parotid swellings. CT and MRI appearances are typical as described. Non-Hodgkin’s lymphoma has bilateral solid masses in the parotids and usually has chronic systemic manifestations. Warthin’s tumours are characteristically inhomogeneous and, if cystic, show mural nodules. Metastatic tumours are solid enhancing lesions and a primary would usually be apparent on further investigation. Pleomorphic adenoma is usually a unilateral, well demarcated, solid, intraparotid lesion with contrast enhancement.

Question 49

(Ped) 50. A 12-year-old boy presents with a slowly enlarging painless lump in the midline of his neck. The lump moves cranially on protrusion of the tongue. Ultrasound shows an anechoic 2 cm cyst in the midline. What is the most likely diagnosis?

(a) Thyroglossal duct cyst

(b) Thyroid adenoma

(c) Thornwaldt cyst

(d) Dermoid cyst

(e) Lymph node

Answer 49

50. (a) Thyroglossal duct cyst

This is the most common congenital neck mass seen in children less than 10 years of age. The thyroglossal cyst typically moves on tongue protrusion. On MRI, the lesion returns low signal on T1 and high on T2.

Question 50

1. Which of the following statements are correct about Thyroglossal duct cyst: (T/F)

(a) Is usually located the level of or immediately below the hyoid bone.

(b) Accounts for 70 % of all congenital neck anomalies.

(c) Is usually located in the midline.

(d) Typically presents as a painful neck lump.

(e) During embryological development, the thyroid gland migrates down behind the hyoid bone.

Answer 50

Answers:

(a) Correct
(b) Correct
(c) Correct
(d) Not correct
(e) Not correct

Explanation:

The thyroid is gland begins to develop in the third week of gestation as a median outgrowth from the floor of the primitive pharynx at the level of foramen Caecum which lies at the junction of the anterior two thirds and posterior third of the tongue. It descends down on the floor of the mouth, anterior to the hyoid bone, to each its final position in the inferior part of the neck by 7th week of gestation. It typically presents as a painless lump. A painful lump can occur if there is imposed infection.

Question 51

31. Regarding thyroid carcinoma, which of the following are correct? (T/F)

(a) Lymph node spread occurs in 90% of patients with papillary cell carcinoma.

(b) Follicular carcinoma accounts for 60% of all thyroid carcinomas.

(c) Early haematogenous spread occurs in follicular carcinoma.

(d) Anaplastic carcinoma demonstrates no radioiodine uptake.

(e) Multiple endocrine neoplasia (MEN) type IIb may be associated with medullary cell carcinoma.

Answer 51

Answers:

(a) Not correct
(b) Not correct
(c) Correct
(d) Correct
(e) Correct

Explanation:

Papillary carcinoma of thyroid accounts for 60%, follicular 20%, anaplastic 10% and medullary 5% . Metastasis to nodes from papillary carcinoma occurs in 40% of adult cases and 90% of child cases.

Question 52

37. Which of the following are correct regarding salivary gland calculi? (T/F)

(a) Most submandibular stones are radio-opaque.

(b) Submandibular stones typically occur within Wharton’s duct.

(c) Asymptomatic Intraductal parotid stones can be an incidental finding on CT.

(d) More than 80% of salivary gland stones occur in the submandibular gland.

(e) About 25% of patients have multiple stones.

Answer 52

Answers:

(a) Correct
(b) Correct
(c) Correct
(d) Correct
(e) Correct

Explanation:

About 10% to 20% of salivary gland calculi occur in parotid gland. About 80% of submandibular stones and 60% of parotid stones are radiopaque.