Pigmented Lesions

Question 1

What are the risk factors for melanoma?

Answer 1

Personal/family history
Number of moles
History of excess sun exposure
Sunbed use
Multiple sunburns
Fair skin

Question 2

Which type of UV light is thought to be responsible for melanoma development?

Answer 2

UVB

Question 3

What are the major and minor criteria for changing moles?

Answer 3

Major:
- change in shape, size or colour

Minor:

• diameter >6mm
• bleeding
• sensory change
• inflammation

Question 4

What is the rule for examining a mole?

Answer 4

ABCD:

• Asymmetry (shape or colour)
• Border (irregular e.g. indentation)
• Colour (>1 colour within the mole)
• Diameter > 6mm

Question 5

What should you use to properly examine a mole?

Answer 5

Dermoscope

Question 6

What are the 4 main types of malignant melanoma?

Answer 6

Superficial spreading (most common)
Lentigo maligna melanoma
Acral/mucosal lentiginous malignant melanoma
Nodular melanoma

Question 7

What are the features of acral MM?

Answer 7

On palms, soles, nail beds and mucosa

Question 8

What are the features of nodular MM?

Answer 8

Raised, thicker lesions

Spread more rapidly

Question 9

What is the most important indicator for prognosis in MM?

Answer 9

Breslow thickness

Question 10

What does the Breslow thickness measure?

Answer 10

Measures the deepest tumour cell from the granular layer of the epidermis

Question 11

Describe the pattern of growth in MM?

Answer 11

First grow as macules within epidermis –> radial growth phase
Then invade dermis forming a lump –> vertical growth phase

EXCEPT nodular MM –> vertical growth from the outset

Question 12

Describe the spread of MM?

Answer 12

Only metastasise once in the VERTICAL growth phase

• local dermal lymphatics (satellite deposits)
• regional lymph nodes
• haematological spread –> skin/soft tissue, heart, lungs, GI tract, liver, brain

Question 13

What is the initial management of a suspected MM?

Answer 13

Narrow complete excision for confirmation of diagnosis and assessment of Breslow thickness
Then wide excision depending on Breslow thickness

Question 14

If in situ (within epidermis), what should the excision margin be?

Answer 14

Clear by 5mm

Question 15

If invasive but Breslow thickness < 1mm, what should the excision margin be?

Answer 15

1cm clearance

Question 16

If invasive and Breslow thickness > 1mm, what should the excision margin be?

Answer 16

2cm clearance

Question 17

When should a sentinel node biopsy be done?

Answer 17

If Breslow > 1cm or thinner with mitoses

Question 18

What are ephilides?

Answer 18

Freckles - patchy increase in melanin pigmentation after UV exposure

Question 19

What are actinic/solar lentigines?

Answer 19

Age/liver spots - related to UV exposure
Face, forearms and dorsal hands
Look like large freckles

Question 20

What are melanocytic naevi and what are the different types?

Answer 20

Moles

• can be congenital but most are acquired in first 2 decades
• usually type, dysplastic, spitz, blue, halo

Question 21

What are the features of congenital melanocytic naevi?

Answer 21

Usually larger than acquired type

If very large garment type (> 20cm) –> risk of melanoma

Question 22

What are the features of dysplastic naevi and what is its malignant potential?

Answer 22

> 6mm, varied pigment, border asymmetry

If familial (lots of dysplastic naevi, Fox of MM)
--> very high lifetime risk of melanoma

Question 23

What is a halo naevus?

Answer 23

Peripheral halo of depigmentation around more due to inflammatory regression

Question 24

What is a blue naevus?

Answer 24

Blue/black colour, entirely dermal mole

Question 25

What is a spitz naevus?

Answer 25

Pink colour due to prominent vasculature
Used to be called benign juvenile melanoma
- occurs in children, closely mimics melanoma but entirely benign