Early forms of squamous cell carcinoma are classified as in situ, which means “in place” in Latin. Squamous cell carcinoma is one of the most common types of skin cancer. It forms when squamous cells begin to grow uncontrollably in the outer part of the epidermis, which is the top layer of our skin. In most instances, it is caused by repeated exposure to UV rays over time.
Squamous cell carcinoma in situ
Early forms of squamous cell carcinoma, also known as Bowen disease, are classified as in situ, which means “in place” in Latin. This simply means that the cancer cells haven’t yet spread beyond the epidermis. When the carcinoma spreads deeper into the skin, into the lymph nodes or organs, it is considered to be metastasized.
Typically, Bowen disease will first appear as a red, scaly plaque of skin, often larger than 1/2 inch across. It can also sometime appear as a hard domed bump. Both varieties typically feel rough and crusty and can bleed when scraped. The cancer usually shows up on areas of the skin that are exposed to the sun, such as the face, ears, lips, arms, legs and tops of hands, but it can also more rarely appear on areas not exposed to the sun including the lower lip and genitals. This cancer usually develops slowly but can spread to the lymph nodes and other organs if left untreated. If caught early though, it is highly treatable.
A doctor will diagnose squamous cell carcinoma with a biopsy. Treatment of the cancer will then vary depending on location, size, severity, how far it has spread and the health of the patient.