Lecture 17 - Thyroid Head, Neck Cancers And Cervical Plexus

Question 1

What is the route of the left recurrent laryngeal nerve?

Answer 1

Branches from vagus nerve
Wraps around the aortic arch
Ascends to larynx in the Tracheoesophageal groove running under the thyroid

Question 2

What is the route of the right recurrent laryngeal nerve?

Answer 2

Branches from the vagus nerve
Wraps around the right subclavian artery and ascends to larynx in the Tracheoesophageal groove passing under the thyroid

Question 3

What are the 2 main arteries supplying the thyroid?

Answer 3

Superior thyroid artery
Inferior thyroid artery

Question 4

Where does the superior thyroid artery branch from?

Answer 4

First branch of the external carotid artery

Question 5

What artery does the inferior thyroid artery branch from?

Answer 5

Thyrocervical trunk

Question 6

What does the thyrocervical trunk branch from?

Answer 6

Subclavian arteries

Question 7

Describe the blood supply to the thyroid:

Answer 7

External carotid artery gives of its first branch called the superior thyroid artery

Subclavian arteries give of the thyrocervical trunk which then branches to the inferior thyroid artery

Question 8

What 3 veins drain the thyroid?

Answer 8

Superior thyroid vein
Middle thyroid vein
Inferior thyroid vein

Question 9

What vein do both the superior and middle thyroid vein drain into?

Answer 9

Internal jugular vein

Question 10

What vein does the inferior thyroid vein drain into?

Answer 10

Left brachiocephalic vein

Question 11

Go to the last slide and label image 1:

Answer 11

1 = vagus nerve
2 = superior laryngeal nerve (external + internal)
3 = internal superior laryngeal nerve
4 = external superior laryngeal nerve
5 = thyroid gland
6 = right recurrent laryngeal nerve
7 = arch of aorta
8 = left recurrent laryngeal nerve
9 = left subclavian
10 = thyrocervical trunk
11 = inferior thyroid artery
12 = left common carotid artery
13 = internal carotid artery
14 = external carotid artery
15 = superior thyroid artery
16 = right subclavian artery

Question 12

Go to the last slide and label the venous drainage of the thyroid (2)

Answer 12

1 = superior thyroid vein
2 = internal jugular vein
3 = middle thyroid vein
4 = inferior thyroid vein
5 = left brachiocephalic vein

Question 13

What membrane do the recurrent laryngeal nerves penetrate??

Answer 13

Cricothyroid membrane

Question 14

What is the general shape of the thyroid gland?
How many lobes are there?
What is the bridge called that joins the 2 lobes of the thyroid gland called?

Answer 14

Butterfly shape
2 lobes

Isthmus = bridge joining the left and right lobe

Question 15

What is the main type of tumour in head and neck cancers?

Answer 15

Squamous cell carcinomas

Question 16

What nerves innervate the thyroid gland?

Answer 16

Sympathetics

Question 17

What investigation method can we use to go through the nose and visualise the pharynx and larynx?

Answer 17

Flexible nasoendoscopy

Question 18

What are the main risk factors for Head and Neck cancers?

Answer 18

SMOKING + TOBACCO (betal nut chewing)
ALCOHOL
Dental hygiene
Viruses like HPV
Premalginant changes

Question 19

What are some premalignant changes that can be seen before head and neck cancers?

Answer 19

Leukoplakia

Erythroplakia

Question 20

What is leukoplakia?

Answer 20

White plaques on the tongue

Question 21

Whta is erythroplakia?

Answer 21

Red plaques on the tongue

Question 22

What virus increases thee risk of oropharyngeal cancer?

Answer 22

HPV

Question 23

What are some risk factors for specifically developing thyroid cancers?

Answer 23

Iridation exposure

FHx and inherited conditions like Familial Adenomatous Polyposis (FAP)

Lumps in < 20yrs lumps in >70yrs

Question 24

Go to the last slide and what premalignant change is image 3 and 4 showing?

Answer 24

3 = leukoplakia
4 = erythroplakia

Question 25

What strucutres can have cancers on in the lip/oral cavity?

Answer 25

Lip Tongue Floor of mouth Cheeks

Question 26

What are the 3 regions of the larynx?

Answer 26

Supraglottis Glottis Subglottis/infra-glottis

Question 27

Who have thyroid goitres more commonly, men or women?

Answer 27

Women

Question 28

What is the staging system for head and neck cancers?

Answer 28

TNM

Question 29

What are the 4 types of thyroid cancer?

Answer 29

Papillary thyroid adenocarcinoma Follicular thyroid adenocarcinoma Medullary carcinoma Anaplastic carcinoma

Question 30

What is the worst type of thyroid cancer?

Answer 30

Anaplastic thyroid carcinoma

Question 31

What cartilage does the thyroid gland sit below?

Answer 31

Thyroid cartilage

Question 32

How does a thyroid cancer present?

Answer 32

Lump in neck (not normally thyroid status issue) Compression symptoms: -Dysphagia -feeling like being strangled Potential voice change

Question 33

What investigations are done if suspected thyroid cancer?

Answer 33

Hx Ex Fine needle aspiration cytology

Question 34

How are thyroid cancers treated?

Answer 34

Thyroidectomy Radioactive iodine (only part of body that uses iodine) Radio/chemotherapy

Question 35

What are the general principles of managing head and neck cancers?

Answer 35

Chemo/radiotherapy Surgical Sample/biopsy Supportive MDT approach

Question 36

What are some supportive treatments needed for Head and Neck cancers?

Answer 36

Help with: -swallowing -feeding -voice rehab -pain

Question 37

How do cancers of the lip/oral cavity present?

Answer 37

Lump Pain (can have refered EAR PAIN) Fixation of tongue (speech issue) Bleeding Dysphagia Odynophagia (pain on swallowing)

Question 38

What Investigations can be done for suspected lip/oral cavity cancer?

Answer 38

Biopsy CT or MRI Possible PET

Question 39

How do PET scans work?

Answer 39

Patient consumes radioactive glucose Glucose used up my highly metabolically active tissues

Question 40

How do you treat a lip/oral cavity cancer?

Answer 40

Small tumours can be excised Radiotherapy May need glossectomy/hemiglossectomy for large tumours

Question 41

How do pharyngeal cancers present?

Answer 41

Lump Pain (can get Otalgia) Dysphagia Odynophagia Weight loss Often present late

Question 42

What investigations are done for pharyngeal cancers?

Answer 42

Imaging: -CT -MRI (include chest)

Question 43

What is usually given to patients with pharyngeal cancer to aid with feeding?

Answer 43

Gastrostomy tube

Question 44

What treatment is given for pharyngeal cancers?

Answer 44

Small tumours excised Radiotherapy Larger tumours not responding to radiotherapy need extensive surgery: Mandibular split Pharyngectomy Robotic procedure

Question 45

What are the 3 key functions of the larynx?

Answer 45

Protecting trachea from food Breathing Speech

Question 46

How do laryngeal cancers present?

Answer 46

VOICE CHANGES (DYPHONIA) Dysphagia Refered otalgia Globus (feels like lump in throat) Neck lump Weight loss Cacexia

Question 47

What investigations are done for laryngeal cancers?

Answer 47

Imaging: -CT (with Cx) -PET -Biopsy

Question 48

What issues do patients with laryngeal cancer usually have after treatment?

Answer 48

Long term voice issues Swallowing problems

Question 49

How do you treat laryngeal cancer?

Answer 49

Small tumours excised Medium sized tumours radio/chemotherapy Large tumours that don’t respond to RT need extensive surgery like LARYNGECTOMY

Question 50

What is a laryngectomy?

Answer 50

Total removal of the larynx The trachea no longer communicates with the pharynx so you ventilate straight through a hole in the neck called a stoma

Question 51

Why cant you speak normally after a laryngectomy?

Answer 51

Vocal cords have been removed

Question 52

What is a tracheostomy?

Answer 52

When a hole is made through the skin with a plastic pipe inserted into the trachea

Question 53

What lymph nodes undergo lymphadenopathy first when a head and neck cancer begins to spread?

Answer 53

Cervical lymph nodes

Question 54

What is the spinal nerve roots of the Cervical Plexus?

Answer 54

C1-C4

Question 55

What fibres of C1-C4 make up the cervical plexus?

Answer 55

Anterior fibres/rami

Question 56

Where is the cervical plexus located?

Answer 56

Halfway up on top of Sternocleidomastoid in the prevertebral fascial layer in the posterior neck triangle

Question 57

Where are the muscular branches of the cervical plexus locatated relative to the sensory branches?

Answer 57

Muscular branches deep to sensory branches

Question 58

What are the 3 main branches of the cervical plexus?

Answer 58

Phrenic nerve Nerve to geniohyoid and thyrohyoid Ansa cervicalis

Question 59

What are the spinal nerve roots of the phrenic nerve?

Answer 59

C3, C4, C5

Question 60

What is the spinal nerve roots of the nerve to geniohyoid and thyrohyoid?

Answer 60

C1

Question 61

What are the spinal nerve roots for the Ansa cervicalis?

Answer 61

C1, C2, C3

Question 62

What does the phrenic nerve innervate?

Answer 62

Diaphragm

Question 63

What route does the phrenic nerve take?

Answer 63

Travels down anterior scalene muscle to thorax passing in front of lung roots

Question 64

What is the nerve route of the geniohyoid and thyrohyoid nerve?

Answer 64

With hypoglossal nerve

Question 65

What is the nerve route of the hypoglossal nerve?

Answer 65

Medulla -> posterior cranial fossa ->hypoglossal canal

Question 66

What is the function of the geniohyoid muscle?

Answer 66

Move hyoid supero-anteriorly

Question 67

What is the function of the thyrohyoid?

Answer 67

Depress hyoid and elevates larynx

Question 68

What is the function of the Ansa cervicalis?

Answer 68

Innervates Infrahyoid muscles which depress hyoid

Question 69

What are the 4 muscular branches of the Ansa cervicalis?

Answer 69

Superior belly of omohyoid Inferioir belly of omohyoid Sternohyoid Sternothryoid

Question 70

What are the 4 sensory branches of the cervical plexus?

Answer 70

Greater auricular nerve Transverse cervical nerve Lesser occipital nerve Supraclavicular nerve

Question 71

What are the nerve roots of the 4 sensory branches of the cervical plexus? Greater auricular nerve Transverse cervical nerve Lesser occipital nerve Supraclavicular nerve

Answer 71

Greater auricular nerve C2-C3 Transverse cervical nerve C2-C3 Lesser occipital nerve C2-C3 Supraclavicular nerve C3-C4

Question 72

What does the greater auricular nerve innervate?

Answer 72

External ear + skin over parotid gland

Question 73

What does the transverse cervical nerve innervate?

Answer 73

Anterior neck

Question 74

What does the lesser occipital nerve innervate?

Answer 74

Posterosuperior scalp

Question 75

What does the Supraclavicular nerve innervate?

Answer 75

Supraclavicular fossa, upper thoracic region and Sternoclavicular joint

Question 76

What is Eros point and what is its clinical relevance?

Answer 76

Point halfway up midpoint of SCM where anaesthetics can be injected in to cause a cervical plexus nerve block

Question 77

What is the most common cause of hyperthyroidism?

Answer 77

Graves’ disease

Question 78

What is a cause of hypothyroidism?

Answer 78

Hashimoto’s disease

Question 79

Why does the thyroid gland move up on swallowing?

Answer 79

Thyroid gland ensheathed in pre-tracheal fascia which attaches to the hyoid bone

Question 80

What muscles overlie the thyroid gland?

Answer 80

Strap/infrahyoid muscles

Question 81

What is the most likely cause of a soft tissue mass that moves up when the patient swallows and sticks their tongue out?

Answer 81

Thyroglossal duct cyst Normally the duct obliterates

Question 82

What anatomical structure does the Ansa cervicalis overlie?

Answer 82

Carotid sheath

Question 83

What muscles do the Ansa cervicalis innervate?

Answer 83

Infrahyoids