Melanoma

Question 1

What are the types of melanoma

Answer 1

Superficial spreading
Nodular melanoma
Lentigo maligna melanoma
Acral lentiginous melanoma

Question 2

Aetiology of malignant melanoma

Answer 2

Genetic: sun-sensitive skin (fair type and susceptibility to burn), specific melanoma-related genes e.g. CDKN2A (encodes P16 and p14ARF proteins), xeroderma pigmentosum
Environmental factors: excessive exposure to solar and artificial UV radiation e.g. tanning beds
It is estimated that only 25% to 42% of melanomas arise in pre-existing naevi
History of sunburns and intermittent high-intensity sun exposure
There is local invasion e.g. into the dermis
Common sites of metastases: lung, bone, brain, liver

Question 3

Risk factors for melanoma

Answer 3

UV light
Family history of skin cancer, melanoma, or atypical naevi
Lighter skin
Personal history of skin cancers
Fitzpatrick skin type I or II
Red/blonde hair
High freckle density
Sun bed use
Light eye colour
Immunosuppression
Xeroderma pigmentosum

Question 4

Symptoms of melanoma

Answer 4

Abnormal skin presentation
- New mole
- Mole that has changed
>50 benign melanocytic naevi
Atypical naevi
Constitutional symptoms (Weight loss, fatigue, night sweats)

Question 5

Signs of melanoma on examination

Answer 5

Examine the skin lesion, good light no magnification:
- “Ugly duck sign” = a nevus that is obviously different from the others in a given individual.
- Altered pigmented lesion (ABCDE)
○ Asymmetry
○ Border is irregular
○ Colour/pigmented
○ Diameter >6mm
○ Evolution (size/shape)
○ May bleed, itch, ulcerate, crust overBluish-white veil
± dermatoscope
- Persistent single-nail melanonychia striata
- Hutchinson’s sign
Lymph nodes
- Fixed lymphadenopathy

Question 6

Describe superficial spreading melanoma

Answer 6

Most common (60-70%)
Any site, preference for torso
Flat, pigmented lesions with asymmetrical or irregular borders
Usually spreads horizontally

Question 7

Describe nodular melanoma

Answer 7

Second most common (15-30%)
Domed shape with rapid growth
Atypical nodules that may ulcerate ad bleed easily
Any site
Lacks ABCDE features

Question 8

Describe lentigo maligna

Answer 8

Flat lesions, often on the face
Irregular shaped brown macule, growth slowly
Most common in older people

Question 9

Describe acral lentiginous melanoma

Answer 9

Palms, soles and nail beds
Variable pigmentation, most often a mixture of brown, blue-grey, black, and red colours.

Question 10

Investigations for melanoma

Answer 10

Dermatoscopy: Melanocytic lesion with abnormal appearance concerning for melanoma
Skin biopsy: Abnormal melanocytic proliferation in the epidermis and/or dermis typical of melanoma

Serum LDH: ?mets

Skin biopsy: abnormal melanocytic proliferation in the epidermis/dermis
CXR/CT CAP/PET/CT: ?mets

Sentinel lymph node biopsy: ?mets

Question 11

How is melanoma staged

Answer 11

Breslow thickness

Question 12

Management for melanoma

Answer 12

2WW referral

Generally: surgical excision ± lymph node biopsy, chemotherapy, immunotherapy

In situ disease (Stage 0) → Surgical excision, Non-surgical destructive or Topical therapy
Thin melanoma (Breslow’s depth < 1mm) + N0/M0 → Surgical excision +/- Sentinel lymph node biopsy
Intermediate thickness (Breslow’s depth 1-4 mm)+ N0/M0 → Surgical excision +/- Sentinel lymph node biopsy
Thick melanoma (Breslow’s depth >4mm) + N0/M0 → Surgical excision +/- Sentinel lymph node biopsy
Nodal (Stage III) → Surgical excision of regional lymph nodes +/- Ipilimumab +/- IFN alfa-2b or Peginterferon alfa-2b
In-transit (Stage III) → Surgical resection or Non-surgical treatment (radiation, fulguration) +/- intralesional therapy
Systemic metatastic disease (Stage 4) → Surgical excision +/- Ipilimumab +/- Pembrolizumab or Nivolumab +/- target therapy for unresectable metastatic BRAF-mutat melanoma +/- Radiotherapy +/- Chemotherapy

Question 13

Prognosis for melanoma

Answer 13

Early-stage melanoma has 100% survival rate
Metastatic melanoma can be fatal Prognosis based on Breslow thickness of tumour and lymph node status
5 year survival rates
- Stage 0 (in-situ melanoma): >98%
- Stage I (Breslow’s depth <1 mm and no nodal or metastatic disease): 90% to 95%
- Stage II (localised disease, intermediate to thick depth): 45%-78%
- Stage III (nodal metastases): 69% (non-ulcerated melanoma of any depth with a single positive node) to 26% (ulcerated melanoma of any depth
with 4 or more positive nodes)
- Stage IV (metastatic): without treatment, overall prognosis is bleak, ranging from 3% to 10% depending on the extent and sites of metastasis.

Over 99% of patients with in-situ melanoma will be cured with simple excision