Can you recover from radiation burns

Pharmaceutical care for skin changes

Skin reactions are dose-dependent. When irradiating non-tumor patients ("inflammatory irradiation") with doses of 5 to 10 Gy, no changes are to be expected, skin reactions rarely occur at 20 to 30 Gy, and erythema formation is common at high doses above 50 Gy. More than 80 percent of radiology departments in the UK observe skin reactions (4). About 80 to 90 percent of these are erythema and 10 to 15 percent wet desquamation (15).

 

Local radiation dermatitis

 

Radiation dermatitis is a local reaction to radiation exposure; a distinction is made between an acute reaction and a late change. Initially, radiotherapy can stimulate the melanocytes in a dose-dependent manner, which gives the skin a darker appearance (11, 28). Appendages such as hair, sebum and sweat glands are also affected; functional impairment or complete hair loss occurs. Dilated microvessels in the dermis and progressive narrowing of the arteries were seen after single high doses of radiation.

 

Skin reactions during or shortly after radiation therapy can range from mild erythema to dry to confluent, moist desquamation (peeling) with blistering. The most serious form is necrosis. Sometimes a combination of erythema, dry and wet desquamation can be observed within a certain area. Later changes can only appear after many months and years in the form of pigmentation, skin atrophy, often combined with telangiectasia and even necrosis (radiation ulcer). A strong early reaction of the skin can heal completely without late changes, a late damage does not have to be the result of a strong early reaction.

 

Trott et al. Reported overexpression of tumor necrosis factor alpha (TNFα), IL-1α and inducible NO synthase after single high-dose irradiation in mouse skin (33). This could be suppressed by anti-inflammatory agents and thus the subsequent moist desquamation could be reduced.

 

Schmuth et al. Measured the TEWL as a sign of epidermal dysfunction during fractional radiotherapy of 50 to 60 Gy in breast cancer patients (29). They found an increase in TEWL from day 11, which preceded erythema, a maximum around day 27, and normalization by day 66. This may mean that the radiation triggers a functional disorder of the keratinocytes, leading to an abnormal extracellular matrix and a deficient one leads to epidermal lipid production. The dysfunction of the barrier could trigger cytokine production, which in turn stimulates inflammation.

 

With normal skin homeostasis, the superficial cells are constantly sloughed off and new ones move from the basal cell layer. Renewal of the entire epidermis takes about four weeks. This is consistent with the length of time it takes basal cells to get to the surface. The basal cell layer proliferates rapidly, making it particularly sensitive to radiotherapy. Basal cell loss begins at a radiation dose of 20 to 25 Gy (1). A maximum of damage occurred in patients treated with 50 Gy. This means that in practice skin reactions become visible around the second to third week of radiation therapy, with a peak at the end of the radiation therapy or within a week afterwards (2, 28).

 

The skin tries to compensate for the damage caused by increased mitotic activity. If the new cells reproduce faster than the old ones are exfoliated, dry desquamation occurs. Wet desquamation occurs when the dividing cells in the basal cell layer are so damaged (often after a skin dose of 50 Gy) that the affected tissue is not replaced. The skin becomes thin, fragile, or atrophic, eroded, and the epidermis breaks (14, 16).

 

Skin reactions are very stressful

 

The skin reaction to be expected depends on the individual and total dose as well as the total treatment time. Increasing doses of radiation lead to hyperpigmentation, epilation and dry epitheliolysis. The extent of the acute reactions essentially depends on the thickness of the stratum corneum. The reactions are lowest on the soles of the feet and palms, followed by the scalp, neck, back and extensor sides of the extremities. The skin of the chest and abdomen, as well as the flexors of the extremities, are moderately sensitive. The front parts of the neck, the elbows and the hollows of the knees are most sensitive to radiation.

 

Doses above 40 Gy lead to increased scaling, then progressive atrophy, telangiectasia and subcutaneous fibrosis. Secondary necrosis and ulcerations can follow.

 

The skin reactions can be very itchy, very uncomfortable and painful. They are often dose-limiting (8), especially with poor radiation quality.

 

Prevention: washing allowed

 

In the early 1920s, the recommendation arose to keep the skin dry with mineral powders such as talcum powder or starch in order to prevent radiation damage. However, this cannot improve the barrier function. Certainly the skin will gradually crack and develop fissures. When they absorb liquid, the powders tend to form lumps and can thus promote mycoses.

 

Washing the irradiation region was not only frowned upon in earlier years, it was even taboo. Meanwhile, many studies show that careful washing does not bring negative results. However, there are still quite a few radiological departments that prohibit their patients from doing this (14, 18).

 

According to current knowledge and experience, the risk of dermatitis has decreased significantly through careful washing and creaming together with radiation techniques that are gentle on the skin. The pH value of the skin is kept stable through moderate washing. The psychological factor for the patient should not be underestimated. A short-term washing ban should only be considered if patients do not comply with the request after washing or showering carefully (37). Otherwise, the skin can swell and this can lead to increased proliferation, which causes an intensified skin reaction.

 

The National Guideline Clearinghouse (5, 21) recommends washing or showering gently with lukewarm water or a mild soap and water. Do not rub the skin when doing this. A mild soap is pH balanced, not perfumed and without lanolin. Overall, personal hygiene should be maintained. Patients with irradiation of the head can use a mild shampoo with about one head wash per week.

 

In one study, showers were allowed three times a week, which was well accepted by patients (30). This prevents chemical irritation from sweating or mechanical skin irritation from powder. The authors confirm that powders dry out the skin and fissures appear, making superinfections possible. If the basal cell layer is destroyed, incomplete healing processes can leave functional disorders, scars or atrophies. The moist skin care maintains the normal permeability of the skin and thereby promotes exchange processes. The irradiated skin remains supple, itching is minimized and the patient does not scratch. Moist packs with lactated ring absorb heat, which is perceived as pleasantly cooling.

 

With wheat and rice starch powder, which have a 5 to 10 times higher water content than mineral powder (39), only a temporary cooling effect can be achieved. In addition, all powder stains clothes and objects such as chairs or bed linen. According to the study (30), since the moist skin program has been running, patients no longer wash themselves secretly, so that the markings are retained. The field markings on the skin should be made with suitable colored pencils and cannot be removed by washing with water!

 

All studies clearly show how difficult it is to maintain patient compliance, especially since the personal experience and convictions of the patient significantly influence washing behavior during radiotherapy. The findings show how important the patient information given in face-to-face meetings is, which can be supported by written material.

 

Applications for dermatitis

 

Washing was superior to dry treatment not only in terms of prevention, but also for the treatment of skin damage in breast cancer patients. Wet desquamation, in particular, was less common when washing was allowed.

 

Xerosis cutis (xeroderma) is a key symptom of radiodermatitis and requires treatment. Conventional soaps should not be used for skin cleansing, as these can shift the pH value to alkaline.

 

In the case of erosive radiation dermatitis, moist compresses with black tea or eosin solution (1 to 2 percent), briefly also hydrocortisone foam, are recommended (23). Eosin not only provides rapid relief, but also drains it and prevents superinfection. There is also limited evidence on the use of calendula ointment in women with breast cancer (24).

 

Many other studies did not provide a clear assessment of topical agents such as corticosteroids, sucralfate cream, ascorbic acid, aloe vera, chamomile cream and almond oil ointment, as well as oral (enzymes, sucralfate) and intravenous agents such as amifostine for the treatment of acute skin reactions (22). The Canadian Supportive Care Guidelines Group recommends the early application of an unscented, lanolin-free hydrophilic cream that maintains the skin's moisture.

 

Reports of the use of corticosteroids to treat skin irritation and itching are controversial. Authors found no effect with hydrocortisone (27). On the other hand, mometasone fumarate was significantly more effective than the cream base alone in a randomized double-blind study with 49 breast cancer patients (7). The use of topical corticosteroids is nevertheless not generally recommended because of side effects such as superinfections or skin atrophy (31). Corticoids can also inhibit local lipid synthesis and thus disrupt the barrier function (17).

 

In summary, one can quote the recommendations of the guideline "Radiation Oncology: Supportive Measures" of the Working Group of Scientific Medical Societies (AWMF) (3). It says here that care by means of washing is superior to the washing ban (evidence level II). With the same level of evidence, benefits for creams with corticoids, sucralfate and hyaluronic acid are seen. In moist epitheliolysis, hydrocolloid dressings were superior to the use of gentian violet (evidence level II).

 

Due to the large number of preparations and the sometimes controversial therapeutic effect for different skin reactions, there is a large variation in the care concepts. An interdisciplinary collaboration on site between pharmacists and radiation oncologists for the benefit of the patient is therefore highly recommended.

 

Experience in the hospital

 

Each radiation therapy patient receives precise information from the treating radiation oncologist about the goals, type and duration of treatment, behavior during and after the radiation period, as well as possible side effects. In addition, it makes sense that the hospital pharmacist and the doctor jointly give a written recommendation on personal behavior and skin care. All patients should be advised on how to optimally care for their skin at the point of entry and exit of the radiation (6, 9, 14, 19, 26). A corresponding project between pharmacists and radiation oncologists is underway at the University of Mainz Clinic.

 

In prophylaxis, preparations of the O / W type have proven particularly useful. Good successes have been achieved, for example, with the in-house “Curaderm skin lotion for radiology” (box). The beginning or already existing exudation can be treated with poultices with black tea, a tannin preparation (example: Tannolact® Cream), tormentill gel or tannin gel from our own production.