Squamous Cell Carcinoma
Squamous Cell Carcinoma is the second most common type of skin cancer that is caused by ultraviolet rays (sunshine), arsenic ingestion, some wart viruses (human papilloma virus), and radiation. Although uncommon, this tumor does have the potential to metastasize (spread to the lymph nodes and internal organs) and can be fatal. Tumors that occur within a burn scar and those that are on the lip or ear are more likely to metastasize than those elsewhere.
Early, non-invasive tumors are called squamous cell carcinoma in-situ (or intraepithelial squamous cell carcinoma or Bowen’s disease), and tumor cells are only present in the epidermis, the top layer of skin. This early variant is not life-threatening unless untreated, in which case it can become invasive with time (months to years).