Malignant Melanoma

Question 1

Are melanomas benign or malignant?

Answer 1

highly malignant

Question 2

Where do melanomas arise from?

Answer 2

the melanocyte layer of the skin situated in the basal layer of the epidermis

Question 3

Summarise the aetiology of melanoma:

Answer 3

ultraviolet radiation causes melanocytic stem cells to undergo a genetic transformation so that they proliferate uncontrollably

Question 4

What is the medical term for moles?

Answer 4

benign melanocytic naevi

Question 5

What is the medical term for freckles?

Answer 5

lentigines

Question 6

Define ‘invasive’ melanoma:

Answer 6

where the tumour has penetrated into the dermis below

Question 7

Define ‘in situ’ melanoma?

Answer 7

where the tumour is confined to the epidermis

Question 8

What are the 4 types of melanoma?

Answer 8

1. Superficial spreading melanoma
2. Nodular melanoma
3. Lentigo maligna melanoma
4. Acral lentiginous melanoma

Question 9

What is the most common type of melanoma?

Answer 9

superficial spreading melanoma

Question 10

Describe the pattern of growth seen in superficial spreading melanoma:

Answer 10

1) they grow horizontally
2) they have a relatively long in situ phase

Question 11

Where are superficial spreading melanomas found?

Answer 11

anywhere in the body but particularly the trunk in males and legs in females

Question 12

What is the most aggressive type of melanoma?

Answer 12

nodular melanoma

Question 13

Describe the pattern of growth seen in nodular melanomas:

Answer 13

they invade vertically rapidly

Question 14

How do superficial spreading melanomas present?

Answer 14

flat, irregularly pigmented lesion that slowly enlarges

Question 15

How do nodular melanomas present?

Answer 15

usually one colour (dark or blue) with a berry-like, symmetrical morphology

Question 16

What percent of melanomas are nodular melanomas?

Answer 16

15 - 30 %

Question 17

What is lentigo maligna melanoma?

Answer 17

melanoma formed from the precursor lentigo maligna, a patch of discoloured skin that grows slowly and becomes more atypical over time

Question 18

Where does lentigo maligna usually occur?

Answer 18

Lentigo maligna usually occurs on the face or other areas of chronic sun exposure as an asymptomatic, flat, tan or brown, irregularly shaped macule or patch with darker brown or black spots scattered irregularly on its surface. In lentigo maligna, both normal and malignant melanocytes are confined to the epidermis.

Question 19

How does acral lentiginous melanoma present?

Answer 19

flat, slowly enlarging pigmented lesion found on the palms, soles or under nails

Question 20

Give 6 risk factors for melanoma:

Answer 20

1) skin cancer history or family history
2) pale skin and red hair
3) increasing age
4) high sun/UV exposure
5) high freckle density
6) large amounts of moles

Question 21

What is the name given to melanomas with no pigment that present as pink/red lesions?

Answer 21

amelanotic melanoma

Question 22

Give the 5 features of the ABCDE Criteria used to assess melanomas:

Answer 22

1) asymmetric shape
2) border irregularity
3) colour change
4) diameter
5) evolving - change in size, shape, colour, bleeding

Question 23

Fill in the gap: most melanomas are under __mm

Answer 23

> 6mm

Question 24

Give two differentials for melanoma:

Answer 24

1) dermatofibroma (pigmented harmless lump)
2) seborrheic keratosis

Question 25

How does seborrheic keratosis present?

Answer 25

waxy, scaly dark lump

Question 26

What type of referral should be used for suspected melanoma?

Answer 26

2 week referral

Question 27

What is the name of the system used to stage melanomas based on their thickness?

Answer 27

Breslow’s thickness

Question 28

Summarise the staging system for melanomas:

Answer 28

1) stage 0 - in situ
2) stage 1 - <2mm thickness
3) stage 2 - >2mm thickness of >1mm thickness with ulceration
4) stage 3 - spread to local lymph nodes
5) stage 4 - metastases to distant sites

Question 29

What is the main management method for melanomas?

Answer 29

wide local excision

Question 30

What investigation can be used to check for local spread of melanomas?

Answer 30

sentinel lymph node biopsy

Question 31

What is the % survival rate for stage 4 melanomas?

Answer 31

7-19%

Question 32

Name two immunotherapies that may be given to late stage melanomas that cannot be resected:

Answer 32

1) Nivolumab
2) Ipilimumab

Question 33

What is the EFG system that is used for nodular melanomas?

Answer 33

E = Elevation, and
F = Firmness to touch, and
G = Growth. Persistent growth for over one month

Nodular melanoma can be brown, black, blue-black, and up to 50% are hypomelanotic (pink-red or skin-coloured). The surface can be smooth, rough, or crusted. Nodular melanoma often lacks dermoscopic clues, and the diagnosis should be considered in any skin lesion demonstrating all of EFG: