What is an an IEC (Intraepithelial Carcinoma) ?
IEC (Intraepithelial Carcinoma is otherwise known as Bowen’s disease. There is a subtle difference between the two terms. Bowen’s is an IEC without a background of sundamaged skin. IEC tends to be the phrase used most often in Australia.
IEC is a type of squamous cell skin cancer but one that is confined only to the upper layer of skin (epidermis) – and is therefore fairly easys to treat. The abnormal squamous cells of an IEC are located throughout the epidermis. The IEC starts life as a Solar Keratosis – when the abnormal squamous cells involve only the lower part (base) of the epidermis.
With time, an IEC may develop into an Invasive Squamous Cell Carcinoma (SCC) – when these cancerous squamous cells haveespread down into the dermis.
So an IEC is intermediate between the ubiquitous Solar Keratosis, and an invasive Squamous Cell Carcinoma. An IEC is a “proper” skin cancer whereas the solar keratosis is, in effect, a “pre-cancer.”
All three of these lesions share the characteristic of sun damaged epithelial cells (keratinocytes) of the Epidermis (upper layer of the skin) caused by sun damage.
What is the risk of a Solar Keratosis turning into an IEC or Invasive SCC?
The risk is around 1-2% per year.