Melanocytic lesions

Question 1

What are the 4 main types of malignant melanoma?

Answer 1

Superficial spreading - (70%)

Nodular - (second most common)

Lentigo maligna - (less common)

Acral lentiginous - (rare)

other rare forms see Passbook

Question 2

Glasgow 7 point checklist for melanomas.

List the major and minor features

Answer 2

Glasgow 7-point checklist:

Major features:

• Change in size
• Irregular shape
• Irregular colour

Minor features:

• Diameter >7mm
• Inflammation
• Oozing
• Change in sensation

Question 3

What is the treatment for malignant melanoma?

Answer 3

Suspicious lesions - excision biopsy for diagnosis

Surgical excision
* thin lesions removed using local anaesthetic (normal skin around excised to ensure melanoma cells removed often done as a second procedure after pathology confirmation)
* >1 mm in thickness - wide local excision post initial excision biopsy. Skin graft may be necessary and local lymph nodes tested ( sentinal node biopsy)

Radiotherapy sometimes
Chemotherapy - metastatic

Question 4

How is the margin of excision to be removed around a malignant melanoma worked out?

Answer 4

Use Breslow thickness of lesion to work out margin of excison

0-1mm thick - 1 cm margin of excision

1-2 mm thick - 1-2 cm (site and pathological features dependant)

2-4mm thick - 2-3 cm (site and pathological features)

> 4 mm thick - 3 cm

Question 5

What is the Breslow depth?

Answer 5

invasion of the depth of a tumour

Question 6

What is used to approximate malignant melanoma 5 year survival?

Answer 6

Breslow thickness again!

e.g.

<0.75 mm - 95-100% 5 year survival

0.76 - 1.50 mm - 80-96%

1.51 - 4mm - 60-75%

> 4mm - 50 %

Question 6

What is a malignant melanoma?

Answer 6

An invasive malignant tumour of the epidermal melanocytes, which has the potential to metastasise

Question 7

What are risk factors for malignant melanoma?

Answer 7

• sun exposure, particularly during childhood fair skin that burns easily (Fitzpatrick phototypes 1 and 2)
• blistering sunburn
• previous melanoma
• previous non-melanoma skin cancer (basal cell carcinoma, squamous cell carcinoma)
• family history of melanoma, especially if two or more members are affected
• large numbers of moles (especially if there are more than 100)
• abnormal moles (called atypical or dysplastic naevi).

Question 8

What are you looking for when a pt presents with a suspicious mole that could be a malignant melanoma?

Answer 8

“ABCDE Symptom”s rule
* = major suspicious features

Asymmetrical shape

Border irregularity

Colour irregularity *

Diameter > 6mm

Evolution of lesion (change size/shape) *

Symptoms e..g bleeding / itching

Question 9

What is this?
Where and who tends to get it?
Related to?

Answer 9

WHAT: Superficial spreading melanoma

WHERE: lower limbs

WHO: young / middle aged adults

RELATED TO: intermittent high intensity UV exposure

Question 10

What is this?
Where and who tends to get it?
Related to?

Answer 10

WHAT: nodular melanoma

WHERE: trunk

WHO: young and middle aged adults

RELATED TO: intermittent high intensity UV exposure

Question 11

What is this?
Where and who tends to get it?
Related to?

Answer 11

WHAT: lentigo melanoma

WHERE: face

WHO: elderly pts

RELATED TO: long term, cumulative UV exposure

Question 12

What is this?
Where and who tends to get it?
Related to?

Answer 12

WHAT: acral lentiginous melanoma

WHERE: common on palms, soles, nail beds

WHO: elderly pts

RELATED TO: no clear relation to UV exposure

Question 13

What staging system in UK used for malignant melanoma? what factors does it use to stage?

Answer 13

2009 American Joint Committee of Cancer Staging System (AJCC)

Stages I-IV
- primary tumour Breslow thickness
- lymph node involvemnet
- evidence of metastases

Question 14

What are the ABCD’s of Melanoma?

Answer 14

• Asymmetry
• Border irregularity
• Colour variation
• Diameter over 6 mm
• Evolving (enlarging, changing)

Question 15

Types of melanomas: Melanomas are described according to their appearance and behaviour. Those that start off as flat patches (i.e. have a horizontal growth phase) include:

Answer 15

• Superficial spreading melanoma (SSM)
• Lentigo maligna melanoma (sun damaged skin of face, scalp and neck)
• Acral lentiginous melanoma (on soles of feet, palms of hands or under the nails – the subungual melanoma)

Question 16

Types of melanoma: Melanomas are described according to their appearance and behaviour. Melanomas that quickly involve deeper tissues include:

Answer 16

• Nodular melanoma (presenting as a rapidly enlarging lump)
• Mucosal melanoma (arising on lips, eyelids, vulva, penis, anus)
• Desmoplastic melanoma (fibrous tumour with a tendency to grow down nerves)
• Combinations may arise e.g. nodular melanoma arising within a superficial spreading melanoma

Question 17

What is a melanoma?

Answer 17

• Normal melanocytes are found in the basal layer of the epidermis, i.e. the bottom part of the outer layer of the skin. The melanocytes produce a protein called melanin, which protects the skin by absorbing ultraviolet (UV) radiation.
• Cancerous growth of melanocytes results in melanoma.

Question 18

What Breslow thickness means a sentinal lymph node biopsy should be carried out? Why?

Answer 18

> 1mm a sentinel node biopsy should be carried out, which can look for evidence of metastases and stage the cancer.

Question 19

Management based on staging for melanocytic lesions

Answer 19

Based on the stage, a wider excision margin may be taken around the lesion to ensure the cancer has been removed:

Stage 0 = 0.5cm
Stage I = 1cm
Stage II = 2cm

Stage III and IV are metastatic, so adjuvant immunotherapy or chemotherapy is given.