Squamous Cell Carcinoma

Question 1

Definition

Answer 1

Malignancy of epidermal keratinocytes of the skin.

o Marjolin’s ulcer is a squamous cell carcinoma that arises in an area of chronically inflamed skin

Question 2

Aetiology/risk factors

Answer 2

· Main risk factor = UV RADIATION
· Sun exposure can lead to actinic keratosis (sun-induced precancerous lesion)

· Other risk factors:
o Radiation
o Carcinogens (e.g. tar derivatives, cigarette smoke)
o Chronic skin disease (e.g. lupus)
o HPV
o Long-term immunosuppression
o Defects in DNA repair (xeroderma pigmentosum)

Question 3

Epidemiology

Answer 3

· SECOND most common cutaneous malignancy (20% of all skin cancers)
· Occurs mainly in MIDDLE-AGED and ELDERLY people
· LIGHT-SKINNED individuals are at higher risk
· 2-3 x more common in MALES

Question 4

Presenting symptoms

Answer 4

· Skin lesion
· Ulcerated
· Recurrent bleeding
· Non-healing

Question 5

Signs on physical examination

Answer 5

· Variable appearance - may be ulcerated, hyperkeratotic, crusted or scaly, non-healing
· Often on sun-exposed areas
· Palpate for local lymphadenopathy

Question 6

Investigations

Answer 6

· Skin Biopsy - confirm malignancy and specific type
· Fine-needle aspiration or lymph node biopsy - if metastasis is suspected
· Staging - using CT, MRI or PET