Skin Cancer

• Skin cancer is the most common malignancy – and the incidence is increasing rapidly
• In the last 10 years, the incidence in the UK has doubled
• Responsible for 2% of cancer deaths each year
• 80% of these are melanoma

• Age
• Sun bed use
• Fair skin
• Hx of sunburn
• Hx of living overseas
• FH
• Occupations – outdoors – e.g. bricklayer
• Phototherapy

• Smoking
• Sun Exposure
• Presence of premalignant lesions
• Age
• Skin trauma
• Exposure to carbon containing compounds
• Asbesotos
• Arsenic
• Ionizing radiation
• Metals
• Non-solar UV radiation – eg. Welders
• 3x more common in men
• Occupational – e.g. builder / farmer – associated with chronic low-grade sun exposure

• Solidary papule / nodule, often eroded at the centre, or crusty, pus-prudcing or bleeding
• Usually a ‘fleshy’ lesion
• May resemble giant warts, but, unlike warts, may be painful
• Usually in a sun-exposed area
• Also related to smoking, and may be present on the lower lip

• Excision with wide surgical margins
• Small tumour – 4mm margin
• Normal margin – 6mm – success rate – 95%
• High risk tumour site – not exposed to sun, lips, anus. These need larger excision to reduce the risk of metastasis (10mm margin)
  • Metastases - rare
  • Lymph nodes

• Proliferation of atypical melanocytes with potential for dermal invasion and widespread metastases.
• Sun exposure still a RF, but not as important as SCC or BCC
• Women - Common on lower legs. Women present sooner – as they are better at checking their bodies!
• Men - Common on back

• 50-70% arise de novo. The rest present at the site of existing ‘moles’
• The average Caucasian has 30 moles
  • You are born with only 1-2
  • Most are acquired in teenage years
  • New moles after the age of 40 are worrying!
• Caution during pregnancy!
  • Malignant melanoma is no more common during pregnancy
  • Moles can change size and become darker during pregnancy
• Rare sites for lesions include mucosa (particularly in the anal region), genital regions and conjunctiva

• Giant congenital naevus >20cm
• FH
• MOLES! >50 moles >2mm size
• Red hair freckles skin types
• Sun exposure – particularly sun burn before the age of 10

• A – asymmetry
• B – border
• C – colour – are there several colours within it?
• D – dark
• E – enlargement

• 15% of cases of melanoma
• Usually on the face (or other sun exposed areas) in elderly patients
• Typically a large, flat, dark lesion

Superficial spreading melanoma

• About 65% of melanomas
• Most commonly on the legs of women, and the torso of men
• Appears like a slightly raised plaque

Nodular Melanoma

• 10-15% of cases
• Anywhere on the body
• Often dark coloured
• Occasionally may be pearly or lack pigment
• Very rarely metastasise, but grow rapidly

Acral and subungal melanoma

• Relatively rare, but the most common melanoma in Black Africans
• Usually seen on the palms or soles, or subungal skin

• Local lymph nodes
• Satellite lesions – usually nearby, nodules or papules that may or may not be pigmented
• Skin
• Internal organs  - rare

• Excision
• 2-5mm margins
• Examine lymph nodes and for organomegaly
• >4mm depthof tumour has >60% chance mets

Prognosis

• This is correlated to the depth of dermal spread, and to the histological appearance. The Breslow thickness is a scale often used as a prognostic indicator:

• Fair skin
• Sun exposure – accumulative lifetime exposre

• Usually nodular
• May be erythematous, or non-pigmented
• May be plaque-like
• May be ulcerated
• They can sometimes crust over, and apparently undergo some healing and reduction in size, but generally, enlargement is slowly progressive.

• Remove the lesion!
• This can be in the form of curette, surgical excision, or cryosurgery.