Squamous cell carcinoma

• Facts:
  Arises from precursor lesion (eg. actinic keratosis)
  Vast majority of head and neck cancer is SCC
  
• History / PE:
  Hard, unilateral, non-tender lymph node in the submandibular or cevical region, in a patient with a smoking hisotry
• Diagnosis:
  Biopsy
• Associated With:
  Bowen's disease (SCC in situ)
  Marjolin ulcers (SCC arises from a burn wound)
• Differential Diagnosis:
  Melanoma
  Basal Cell Carcinoma
  Keratoacanthoma
• Risk Factors:
  1) Sunlight exposure is the most important risk factor
  2) Smoking
  3) Arsenic and radiation exposure