Benign and Malignant melanocytic lesions

Question 1

What are melanocytes?

Answer 1

found in epidermis produce melanin give your skin colour

Question 2

What is a naevus (or mole)?

Answer 2

Naevus refers to an abnormal by benign proliferation of melanocytes in the skin

Question 3

What is a congenital naevus?

Answer 3

present at birth uncommon

Question 4

What is a junctional naevus?

Answer 4

maculardark

Question 5

What is an intradermal naevus?

Answer 5

raised and skin colour

Question 6

What is a melanoma?

Answer 6

malignant proliferation of pigment producing melanocytes of the skin

Question 7

What are the risk factors for melanomas?

Answer 7

• fair skin (type 1/2)
• excessive sun exposure in childhood
• family history
• immunosuppressed patients
• patients with multiple atypical moles
• large congenital naevi
• old age

Question 8

What important features associated with poor prognosis in melanomas?

Answer 8

lesions on head and neck 
man 
older age
ulceration 
tumour thickness

Question 9

What are the seven checklist points of melanomas?

Answer 9

1 - changing or irregular colour
2 - irregular shape, asymmetry 
3 - changing size
4 - oozing, crusting or bleeding 
5 - change in sensation, itching 
6 - inflammation 
7 - largest diameter >7mm

Question 10

What is the ABCD rule for describing melanomas?

Answer 10

A - asymmetry
B - border
C - colour
D - diameter (most normal moles are <7mm diameter)

Question 11

What are the different subtypes of melanoma?

Answer 11

Superficial spreading melanoma (SSM) - 70%
Lentigo maligna melanoma (LMM)
Acral Lentiginous
Nodular melanoma

Question 12

What is SSM?

Answer 12

Superficial spreading melanoma

Question 13

Where is SSM common?

Answer 13

Common on lower limbs in young and middle aged adults Related to intermittent high intensity UV exposure

men - commonly trunk
women - commonly legs

Question 14

Where is nodular melanoma common?

Answer 14

common on trunk in young middle aged adults

related to intermittent high intensity UV exposure

Question 15

What is acral lentigious melanoma?

Answer 15

common on palms, soles and nail beds in elderly population

more common in darker skin individuals (afro-carribeans)

no clear relation to sun exposure

Question 16

What is lentigo maligna melanoma?

Answer 16

common on the face in elderly population related to long term cumulative UV exposure

Question 17

What are the benign lesions that can mimic melanoma?

Answer 17

atypical moles 
blue naevus 
seborrhoeic wart
pigmented BCC
dermatofibroma 
pyogenic granuloma

Question 18

What is the management of melanoma once a diagnosis has been confirmed?

Answer 18

Wide local excision using 1-2cm peripheral margin
Lymph node clearance for regional metastasis
No specific treatment for distant metastasis

Question 19

What are congenital melanocytes naevi?

Answer 19

Melanocytes which fail to mature or migrate in utero

Question 20

What are acquired melanocytic naevi?

Answer 20

develop after birth - usually before age of 25

Question 21

What are the different types of melanocytes naevi?

Answer 21

junctional
- macular compound
- warty dermal
- smooth and dome shaped
halo naevus
- undergoing recession, benign often blue naevus
- melanocytes in dermis, usually benign, often extremities

Question 22

What is the 5 year survival for melanocytes naevi?

Breslow thickness

Answer 22

in-situ - 100%
depth less than 1.5mm - 90%
1.50-3.00mm - 60%
greater then 3.00mm - 40%

Question 23

What are the different types of congenital naevus?

Answer 23

giant congenital naevi - increased risk of melanoma

cafe au lait - congénital tan macule, usually oval in shape

Question 24

How are lentigo maligna/ lentigo maligna melanoma managed?

Answer 24

surgical excision with 5mm margin (due to risk of melanoma)

excellent prognosis

Question 25

What is the difference between lentigo maligna and lentigo maligna melanoma?

Answer 25

becomes lentigo maligna melanoma when malignant cells invade dermis

lesion thickens
increasing variability in colour
may have ulceration, bleeding, itching or stinging

Question 26

What is the most aggressive form of melanoma?

Answer 26

nodular melanoma

Question 27

What is the management of melanomas?

Answer 27

initial excision with 2mm skin margin 
followed by wide excision with margins based on breslin thickness 
in situ - 5mm
<1mm - 1cm 
1-2mm - 2cm 
>2mm - 3cm 
1 cm per 1 mm thickness

lymph node clearance
no standard treatment for metastatic disease

Question 28

How should patient with melanomas be followed up after treatment?

Answer 28

3 monthly for 3 years if <1mm depth

further 2 years at 6 monthly intervals if >1mm