By – Ray Lin, MD
Medical Director, Department of Radiation Oncology
An estimated 1.6 million cases of cancer will be diagnosed in the United States in 2016, making cancer among the top two leading causes of death in the United States. More than half of all patients undergoing cancer treatments will receive radiation therapy at some point during their treatment course. Most patients receive radiation therapy externally through equipment known as linear accelerators.
Over 90% of patients undergoing ionizing external beam radiation therapy will develop an acute skin reaction. Radiation dermatitis is the most common side effect of external beam radiation therapy. Symptoms can develop within hours to a few weeks after beginning radiation therapy and can last up to several weeks to months following treatment.
Radiation therapy can injury the skin acutely through the formation of free radicals which can cause irreversible double stranded DNA breaks. Subsequently, the integrity of the skin can be compromised resulting in an inflammatory response in the epidermis and dermis. Radiation dermatitis can range in severity among patients. The intensity of the dermatitis is usually related to amount of overall radiation dose delivered to skin, volume of skin irradiation, area being treated, type and intensity of beam and beam energy, choice of equipment, and type of treatment (conventional, 3D-confromal, IMRT) selected. Patient related factors such as age, smoking history, skin integrity, nutritional status and other comorbidities such as diabetes or kidney disease can also affect the severity of radiation induced skin reactions. Radiation dermatitis can be extremely uncomfortable, often affecting a patient’s quality of life. Skin reaction can vary from mild redness (erythema), soreness, peeling, dryness and swelling, to itchiness, to the development of a rash or papules, to skin ulcers and skin necrosis.
Good skin care and proper hygiene is always advised for patients receiving radiation therapy. Recommendations for patients undergoing treatments include using a mild soap and non-aluminum deodorants, wearing loose-fitting clothes, gentle care of the skin, using a soft washcloth when bathing in lukewarm water, and protection of the skin from the sun. Do not swim in a chlorinated pool if there is a skin reaction. Do not scratch or rub the skin. Avoid makeup, perfumes, powders, and aftershave on the area under treatment.
Radiation Oncologists can sometimes help reduce the intensity of skin reaction through selection of treatment techniques such as intensity modulated radiation therapy when indicated. Often, mild corticosteroids can be used for itchiness and silver sulfadiazine (topical antibiotic) can be prescribed. It is important for patients to moisturize their skin often; in the morning, after therapy, and before bedtime. Do not wash off the moisturizer before therapy. It is important to minimize skin abrasions and irritations. Most acute skin reaction will resolve within a few weeks after therapy. Patients, though, should continue to moisturize their skin for months after completion of radiation therapy. Other treatments during and after therapy can range from using calendula (extract from marigold plant with anti-inflammatory properties) to using dressings (such as hydrogel or hydrocolloid), emulsions, creams and ointments.
Your health care provider should be informed of any non-healing ulcers, temperature of over 101 F, drainage from the skin, pain, and blistering of the skin. It is important to reduce radiation dermatitis. Preventing and proper care of skin reactions can help minimize long-term skin issues such as chronic swelling, skin induration, and fibrosis.