Radiation dermatitis is defined as skin changes resulting from exposure to ionizing radiation. There are reversible effects, i.e., erythema, epilation, suppression of sebaceous glands, and pigmentation that lasts for weeks to months to years, and irreversible effects, i.e., acute and chronic radiation dermatitis and radiation-induced cancers.
Causes of Radiation Dermatitis
- High exposure to radiation can cause significant damage to the skin (radiodermatitis).
- Small blood vessels (capillaries) break down, resulting in changes in the color of the skin.
- Neoplastic transformation develops in the ulcers or the keratoses.
Symptoms of Radiation Dermatitis
The skin becomes dry, fine, and hairless due to atrophy of the epidermis, and is easily vulnerable to minor trauma.
Hyperkeratotic plaques and painful keratoses form on the sides of the fingers and fingertips
Treatment
Chronic radiation dermatitis is permanent, progressive, and irreversible. Squamous cell carcinoma (SCC) may develop in 4 to 39 years, with a median of 7 to 12 years, almost exclusively from the chronic repeated types of exposures. SCC always develops within the area of radiodermatitis, never in normal skin. The tumors are often multiple and metastasize late in about 25%; despite extensive surgery (excision, grafts, etc.), the prognosis is poor, and recurrences are common. In recent years there has been about an equal incidence of SCC and basal cell carcinoma (BCC). BCC appears mostly in patients formerly treated with x-rays for acne vulgaris and acne cystica or epilation (tinea capitis). The tumors may appear 40 to 50 years after exposure. Excision and grafting is often possible before the cancer develops.
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