In-Situ vs. Invasive: SCC in-situ (also known as Bowen's disease) means the cancer cells are confined to the very top layer of the skin (epidermis), while invasive SCC means they have grown deeper into the skin layers. What is squamous cell carcinoma in situ?

Understanding the Context

Squamous cell carcinoma in situ is the early stage of SCC (stage 0). 1 In SCC in situ, can cells exist only in the very top layer of the... What is squamous cell carcinoma in situ? Squamous cell carcinoma in situ (SCC in situ) is a growth of cancerous cells located in the outer layer of the skin.

Key Insights

It is often called ‘Bowen disease’ or ‘Intraepidermal carcinoma (IEC)’. Squamous cell carcinoma in situ is made up of malignant (cancerous) cells. However, because the abnormal cells remain confined to the epidermis, they cannot spread to lymph nodes or distant parts of the body. For this reason, when treated early, squamous cell carcinoma in situ is usually curable. Squamous cell carcinoma in situ is an early, non-invasive skin cancer that’s highly treatable.

Final Thoughts

Learn how to recognize it and what to expect from treatment. Squamous cell carcinoma in situ is an early form of squamous cell carcinoma that is confined to the outer layer of the skin (epidermis) and has not yet invaded the deeper layers. Squamous Cell Carcinoma in Situ - Skin Disorders - Merck Manual ... Squamous cell carcinoma may look like a firm, dome-shaped growth that’s crusty and getting larger. This scaly, dry-looking, rough skin (circled) is squamous cell carcinoma in situ, the earliest form of this skin cancer. View more pictures of what squamous cell carcinoma can look like.