Benign and malignant melanocytic naevi

Question 1

What are the 3 layers of the skin?

Answer 1

epidermis

dermis

fat

Question 2

Where do melanocytes normally reside?

Answer 2

the base layer of the epidermis

Question 3

What are moles/naevi?

Answer 3

nests of melanocytes

Question 4

What are the types of benign melanocytic naevi?

Answer 4

FRECKLES

MOLES:

Acquired:

1) Junctional naevus
2) Compound naevus
3) Intradermal naevus
4) Atypical naevus

Congential

Question 5

What are the types of atypical naevus?

Answer 5

Blue naevus

Halo naevus

Question 6

What is the difference between moles and freckles?

Answer 6

Freckles - melanocytes line the basal layer of epidermis

Moles - melanocytes have formed nests

Question 7

When do acquired moles generally appear?

Answer 7

late childhood to early adolescence

Question 8

How do junctional, compound and intradermal naevus’ link?

Answer 8

The are essentially the ageing process of a mole

Question 9

In what layer are junctional naevi?

Answer 9

Most internal portion of epidermis

Question 10

What shape + colour are junctional naevi?

Answer 10

Flat and dark

Question 11

What is more common acquired or congential moles?

Answer 11

acquired

Question 12

What is the management of atypical naevi?

Answer 12

Excised as clinically difficult to say its 100% benign

Question 13

What is the risk with atypical naevi?

Answer 13

The pt is at greater risk of developing melanoma

Question 14

What are the risk factors for developing malignant melanoma?

Answer 14

Increased UV exposure (most common)

Family history (can be familial)

Previous melanoma

Multiple dysplastic naevi
Large congenital naevi

Question 15

Is genetic testing available for familial milignant melanoma?

Answer 15

Yes

Question 16

What are the referral criteria for melanoma? (scoring only NOT the actual features)

Answer 16

7 point checklist (refer if score ≥3)

split into minor (1 point each) and major features (2 points each)

Question 17

What features are included in the referral criteria for melanoma?

Answer 17

Major: (2 points)
Changing colour
Changing shape
Changing size

Minor: (1 point)
Bleeding
Inflammation
Itching
Diameter >7mm

Question 18

Explain the ABCDE rule for describing a potential melanoma?

Answer 18

A symmetry
B order is irregular
C olour (multiple)
D iameter >6mm
E nlarging/E volving

Question 19

What are the different subtypes of melanoma?

Answer 19

in-situ melanoma
(Lentigo maligna - a subtype of insitu)

INVASIVE types:

Superficial spreading melanoma

Nodular melanoma

Lentigo maligna melanoma

Acral melanoma

Question 20

Where do lentigo maligna most commonly occur?

Answer 20

On the face of elderly people

Question 21

What precedes lentigo maligna’s?

Answer 21

Solar lentigo’s

Question 22

Describe how solar lentigo’s develop into lentigo maligna’s.

Answer 22

Over several years

They change in size, shape and colour

Question 23

What is the most common type of invasive melanoma? (what %)

Answer 23

superficial spreading melanoma (70%)

Question 24

What are the characteristics of superficial spreading melanoma?

Answer 24

Thin and

expand radially

Question 25

What is the prognosis of lentigo maligna melanoma?

Answer 25

It has a good prognosis

Question 26

What does lentigo maligna melanoma arise from?

Answer 26

lentigo maligna

Question 27

What is acral melanoma?

Answer 27

melanoma characterised by its site of origin: palm sole or beneath the nail (subungual melanoma)

Question 28

Who is acral melanoma more common in?

Answer 28

dark skin individuals

Question 29

How quickly does acral melanoma invade?

Answer 29

Quickly

Question 30

What are the benign differentials of melanoma?

Answer 30

atypical naevus blue naevus seborrheic wart dermatofibroma pyogenic granuloma

Question 31

What is the most common type of firm lesion found on the arms and legs?

Answer 31

Dermatofibroma

Question 32

If an atypical naevus is found how should you assess its risk for malignancy? (on a very basic level)

Answer 32

Ugly duckling sign: Look at other moles and if it stands out it is more likely to be a melanoma

Question 33

What are the malignant mimics of melanoma?

Answer 33

BCC SCC

Question 34

On what does the prognosis of melanoma depend?

Answer 34

The depth of invasion

Question 35

What is the special name for the depth of invasion of melanoma?

Answer 35

Breslow thickness

Question 36

What is the management of melanoma?

Answer 36

1. Confirmation via histology 2. Wide local excision (2cm margin) 3. If palpable lymph nodes then lymph node clearance for regional metastasis is done.

Question 37

What is the treatment strategy for distant melanoma mets?

Answer 37

There is no standard regime

Question 38

Does sentinal node biopsy increase survival? (its where you inject dye into skin to find 1st draining lymph node, where it is removed and sent for histology)

Answer 38

It has not been shown to increase survival

Question 39

Is someone burns in the sunlight in 10 mins, how long will it take for them to burn with SPF 15 suncream on?

Answer 39

150 mins

Question 40

What is the prevelance of atypicals moles?

Answer 40

~4%

Question 41

How doe nodular melanomas tend to invade?

Answer 41

Vertically

Question 42

What is the prognosis of melanoma depending on breslow thickness?

Answer 42

5-year survival: in situ 100% Less than 1mm ~95% 1-3mm ~70% grtr than 3mm ~40% or less