Skin Cancer

Question 1

What do you ask if someone presents with a new lesion?

Answer 1

• Has it grown, changed colour or shape?
• Need to know about risk factors - skin type, immunosuppressed, FH, sunbed use, smoker
• Cigarette smoking&raquo_space;» squamous cell skin carcinoma

Question 2

What are risk factors for basal cell carcinoma?

Answer 2

• Chronic UV light exposure
• Fitzpatrick Skin Type 1 and 2
• Chemicals
• Immunosuppression
• Genetic - Gorlin’s syndrome

Question 3

What are risk factors for squamous cell carcinoma?

Answer 3

• Chronic UV light exposure
• Fitzpatrick Skin Type 1 and 2
• Chemicals
• Immunosuppression
• Cigarette smoking
• Chronic ulcers
• Genetic - xeroderma pigmentation

Question 4

What is Gorlin’s Syndrome?

Answer 4

A genetic condition resulting in the mutation of Tumour Suppressor Gene PTCH1. It results in the development of multiple early onset BCCs.

Question 5

What is Xeroderma Pigmentosum?

Answer 5

Autosomal recessive condition resulting from a deficit in DNA repair. This results in extreme sun sensitivity and a predilection for skin cancer.

Question 6

What are the Fitzpatrick Skin types?

Answer 6

1. Type I: always burns, never tans, very pale white skin, blue/hazel eyes, red/blonde hair
2. Type II: usually burns, tans poorly, pale white skin, blue eyes
3. Type III: tans after initial burn, darker white skin
4. Type IV: tans easily, burns minimally, light brown skin
5. Type V: tans darker, brown, rarely burns, brown skin
6. Type VI: always tans darkly, never burns, dark brown/black skin

Question 7

How would you examine if you suspected a malignant lesion?

Answer 7

Check the whole body for other lesions and evidence of photodamage. If suspecting a malignant lesion, then check for evidence of metastases, particularly draining lymph nodes and hepatomegaly.

Question 8

Describe squamous cell carcinoma

Answer 8

Primary cutaneous SCC is a malignant tumour arising from the keratinocytes of the epidermis and its appendages. Tumours can invade locally and have the potential to metastasise to other areas of the body. SCCs can arise de novo, but can also develop from precursor lesions.

Question 9

How does SCC present?

Answer 9

• SCCs usually present as solitary, firm, erythematous papules arising from indurated nodular lesions. Commonly they have crusted or hyperkeratotic surfaces.
• Occasionally lesions are ulcerated and rarely there are verucous forms which can be mistaken for viral warts.
• Lesions are often painful and grown rapidly (over a few weeks to a couple of months).
• Common sites are the face, scalp and back of hands
• They are rare <60yrs but patients on immunosuppressive drugs are at particular risk and may present earlier.

Question 10

What may histology of SCC show?

Answer 10

• Reduced stroma with lymphocytes
• Nests of tumour cells
• Keratinous pearls

Question 11

What genes are thought to be involved in SCC?

Answer 11

Mutations of BCL2 and RAS genes are believed to contribute to the pathogenesis of SCC. Alterations in intracellular signal transduction pathways, including the epidermal growth factor receptor (EGFR) and cyclo-oxygenase (COX), have also been shown to play a role in the development of SCC.

Question 12

What are the features of actinic/solar keratoses?

Answer 12

• Multiple lesions
• Often head and neck
• Not indurated, ulcerated or painful
• Dysplastic keratinocyte cells as base of epidermis
• Ideal treatment is 5% 5-fluorouracil (Efudix) cream

Question 13

What are the features of Bowen’s disease?

Answer 13

• Single plaque
• Often legs
• Not indurated, ulcerated or painful
• Full thickness dysplasia of epidermis
• Risk of progression to SCC is 1/25
• Ideal treatment is cryotherapy

Question 14

What clinical features of SCC suggest a poorer prognosis?

Answer 14

• Tumours >2cm in size are twice as likely to metastasise
• Lesions on the lip or ear
• Immunosuppression (tumours histologically more aggressive)

Question 15

What histological features of SCC suggest a poorer prognosis?

Answer 15

• Invasion >4mm
• Perineural invasion
• Nuclear atypia (poorly differentiated cells) have a poorer prognosis with increased risk of metastasis

Question 16

What is the treatment for SCC?

Answer 16

Surgical excision with adequate margins is the treatment of choice for high risk SCCs (on the ear in immunosuppressed patient will need referral to ENT or plastics)

Question 17

What are tips to reduce the risk of skin cancer?

Answer 17

• Use sun cream and check star ratings (UVA protection - 3/4) - UVB and UVA
• Spend time in the shade between 11am and 3pm
• Never burn
• Wear a hat when in the sun
• Wear close weave clothing (to avoid light getting through the gaps)

Question 18

What are safety nets for future lesions?

Answer 18

• New lesions on skin >/= 3 months
• Anything crusting, scabbing, bleeding
• Growing quickly

Question 19

What are features of BCCs?

Answer 19

• Commonest type of skin cancer
• Slow growing tumours that rarely metastasise
• Commonest type is nodular
• Typically pearly translucent nodule and telangectasia (tiny blood vessels seen in skin)

Question 20

What are risk factors for BCCs?

Answer 20

• Previous SCC

- Immunosuppressed

Question 21

What are high risk BCCs?

Answer 21

• Lesions involving the eyelid margins, ear and lip
• Perineural invasion on histology
• Recurrent lesion
• Lesions in immunosuppressed patients

Question 22

What are the treatment choices for BCCs?

Answer 22

• Imiquimoid cream 5%
• Surgical excision
• Photodynamic therapy
• Radiotherapy
• Conservative

Question 23

How is treatment decided for BCCs?

Answer 23

Determined by site, size and histological subtype, along with patient preference. Given they are slow growing tumours that rarely metastasise it may be reasonable to leave them alone.