D04.70

Clinical Causes: Prolonged exposure to ultraviolet (UV) radiation from the sun or tanning beds Fair skin that is more susceptible to sun damage History of frequent sunburns, especially during childhood Use of tanning lamps or excessive sun exposure without protection Weakened immune system, which may reduce the body's ability to repair skin damage Presence of precursor lesions such as actinic keratosis, which can develop into CIS

Key Symptoms: Persistent or scaly patches on the skin that may be reddish, pink, or skin-colored Lesions that are slightly raised or rough to the touch Lesions that may bleed or crust easily Slow-growing patches that do not heal over time Absence of pain or significant discomfort in early stages

Diagnosis Path: Diagnosis often begins with a physical examination of the affected skin. Physicians may perform a biopsy, where a small sample of the lesion is removed and analyzed under a microscope to confirm the presence of carcinoma in situ. Additional diagnostic tools such as dermoscopy or imaging may be used to assess the extent of the lesion and rule out invasion into deeper tissues. Accurate diagnosis is essential for determining the best course of action and to distinguish CIS from invasive skin cancers.

Treatment Protocols: Treatment options aim to remove or destroy the abnormal cells to prevent progression to invasive cancer. Common approaches include: - Surgical excision to physically remove the lesion - Cryotherapy (freeze treatment) to destroy abnormal cells - Topical medications such as 5-fluorouracil or imiquimod to induce lesion regression - Curettage and electrodessication for superficial lesions - Photodynamic therapy that utilizes light-activated medicines Follow-up examinations are important to monitor the skin and detect any new or recurring lesions. Early treatment of carcinoma in situ generally results in excellent outcomes, emphasizing the importance of regular skin checks and sun protection measures.