D04: Carcinoma in situ of skin

Carcinoma in situ of the skin refers to a group of conditions where abnormal cells have been found in the uppermost layer of the skin, or the epidermis. At this stage, the cells are abnormal but have not spread or invaded any of the surrounding tissues. Being a carcinoma in situ means it’s the earliest stage of skin cancer, not yet being invasive or metastasizing to other parts of the body. Though the causes can be multiple, some of the most common ones include excessive exposure to ultraviolet (UV) sunlight, having light skin color, a family history of skin cancer, and continual exposure to environmental toxins. Symptoms usually include changes in skin such as new growths, sores that don't heal, or changes in existing moles like shape, color, or size. The condition progresses differently for each individual, but if left untreated, the abnormal cells can multiply and become invasive, affecting deeper layers of skin and potentially other body systems.