Cutaneous SCC

• Cutaneous squamous cell carcinoma:

  • Invasive (cancer cells beyond epidermis) SCC that can metastasise and prove fatal
  • Squamous cells are flat cells that make up the outer part of the epidermis
  • Squamous cells start from keratinocytes
• Risk factors:

  • Typically seen in elderly males
  • Previous skin cancers
  • Actinic keratoses
  • Sun exposure
  • Smoking
  • Fitzpatrick skin types I+II
  • Ionising radiation, arsenic, immune suppression
  • Organ transplant recipients
  • Certain genetic conditions - xeroderma pigmentosum
• Clinical features:

  • Enlarging scaly/crusted lumps - commonly bleed if caught
  • Grows over weeks to months
  • Can ulcerate
  • Often tender/painful
  • Found on sun exposed sites
  • Size varies from a few mm to several cm
• Distinct clinical types:

  • Cutaneous horn
  • Keratocanthoma
  • Carcinoma cuniculatum
  • Marjolin ulcer
• Cutaneous horn:

  • Horn due to excessive production of keratin
  • Horns can arise from benign lesions (e.g. seborrhoeic keratosis) as well as SCC
  • Need referral for excision and histology
• Keratoacanthoma:

  • Rapidly growing locally destructive keratinising nodule
  • Not cancerous but behave and look like a well differentiated SCC - sharply demarcated, firm, erythematous or skin coloured, central hyperkeratotic plug
  • Can resolve spontaneously but the clinical course can be unpredictable
  • Treated as if SCC and surgically excised as very locally destructive
• Carcinoma cuniculatum:

  • rare slow growing warty tumour - low grade SCC, can metastasise in rare cases
  • Usually on the foot - can occur in oral cavity, nails or genitals
  • Usually treated with surgical excision
• Marjolin ulcer:

  • SCC that develops in a scar or chronic ulcer - most commonly at site of old thermal burn scar
  • On average develops 30 years after injury
  • Presents as a non-healing sore - suspect when a ulcer persists for >3 months at site of scar
  • Diagnose with biopsy and treat with excision
• High risk SCC characteristics:

  • 2 or more cm in diameter
  • Location on ear, lip, central face, hands, feet or genitalia
  • Elderly or immune suppressed
  • Histological finding of >2mm thickness
• Diagnosis:

  • 2WW to dermatology
  • If suspicious - biopsy/excision to confirm diagnosis
  • If high risk patient and concerned about metastases patients may have staging imaging e.g. CT/MRI, lymph node biopsy
• Staging:

  • TNM
  • Metastasises to:
  • Lymph nodes
  • Lungs
  • Liver
  • Brain
  • Bones
  • Skin
• Treatment:

  • Most cases have surgical excision - may need flap or skin graft o repair the defect
  • Low risk tumours sometimes treated with shave, curettage or cryotherapy
  • If metastasised may need combination of surgery, radiotherapy and immunotherapy