Cutaneous squamous cell carcinoma (SCC) is a common type of keratinocytic or non-melanoma skin cancer. It is derived from cells within the epidermis that make keratin — the horny protein that makes up skin, hair and nails.
Cutaneous SCC is an invasive disease, referring to cancer cells that have grown beyond the epidermis. SCC can sometimes metastasise (spread to distant tissues) and may prove fatal.
Risk factors for cutaneous SCC include:
Age and gender: SCCs are particularly prevalent in elderly males. However, they also affect females and younger adults.
Previous SCC or other form of skin cancer (basal cell carcinoma, melanoma)
Inherited syndromes: SCC is a particular problem for families with xeroderma pigmentosum and albinism
Other risk factors include ionising radiation, exposure to arsenic, and immune suppression due to disease (eg chronic lymphocytic leukaemia) or medicines. Organ transplant recipients have a massively increased risk of developing SCC.
Cutaneous SCCs present as enlarging scaly or crusted lumps. They usually arise within pre-existing actinic keratosis or intraepidermal carcinoma.
The following agents can be used to lighten epidermal melanosis, alone or, more effectively, in combination:
They grow over weeks to months
They may ulcerate
They are often tender or painful
Located on sun-exposed sites, particularly the face, lips, ears, hands, forearms and lower legs
Size varies from a few millimetres to several centimetres in diameter.
Diagnosis of cutaneous SCC is based on clinical features. The diagnosis and histological subtype is confirmed pathologically by diagnostic biopsy or following excision.
Patients with high-risk SCC may also undergo staging investigations to determine whether it has spread to lymph nodes or elsewhere. These may include:
Imaging using ultrasound scan, X-rays, CT scans, MRI scans
Lymph node or other tissue biopsy
Cutaneous SCC is nearly always treated surgically. Most cases are excised with a 3–10 mm margin of normal tissue around the visible tumour. A flap or skin graft may be needed to repair the defect.