The Effect of Mepilex Lite Dressings on Acute Radiation-Induced Skin Reactions in Women Receiving Post-Mastectomy Chest wall Irradiation

Abstract

Acute radiation-induced skin reactions are the most common side-effect of external beam radiation therapy ranging from changes in skin colour to dry and flaky skin, leading to moist desquamation (ulceration). Severe skin reactions compromise quality of life; however, there is currently no standard treatment. Treatment is therefore based on historical and/or anecdotal data which has resulted in substantial variation in skin care practice. A multicentre, intra-individually controlled, randomised trial was conducted to investigate whether Mepilex Lite dressings are superior to the standard departmental care in reducing the extent of acute radiation-induced skin reactions in patients receiving treatment for breast cancer post-mastectomy. Mepilex Lite (Mölnlycke Health Care LTD, Göteborg, Sweden) is a thin, self-adhering, absorbent, soft silicone dressing which was hypothesised to reduce reactions by protecting the irradiated skin against mechanical damage caused by friction and abrasion from clothing or adjacent tissue. This thesis analyses the results of 13 patients recruited at the Regional Cancer Treatment Services who were a subset of the large 80 patient multicentre trial. From the first sign of erythema on the chest wall, the erythematous patch was divided into two equal halves; one half was randomly assigned to be covered in Mepilex Lite dressings, the other to be treated with aqueous cream. Once erythema advanced to moist desquamation, skin under the control patch was dressed with dressings that were standard to the department while the intervention patch continued to be treated with Mepilex Lite dressings. The Modified Radiation-Induced Skin Reaction Assessment Scale (RISRAS) was used to assess the visual signs (researcher component) of the skin reaction while the patient component assessed symptomatic changes for at least three times a week during radiation therapy and once a week post-treatment until all reactions were resolved. An exit questionnaire was filled out by each patient upon completion of the trial allowing them to comment on the different aspects of the trial including their experience with using the Mepilex Lite dressings. Mepilex Lite dressings decreased the severity of skin reactions by 38% (p=0.002) based on the mean combined (patients and researcher) RISRAS scores. Patient RISRAS scores heavily influenced this score, showing a decrease of 77% (p=0.004) compared to the researcher scores which showed a decrease of 19% (p=0.008). Analysis of the peak RISRAS scores to assess the difference in the maximum severity of the skin reactions under each arm showed a similar trend. Combined peak RISRAS showed a decrease of 43% (p=0.005), with a patient component of 74% (p=0.006) and a researcher component of 20% (p=0.026). Analysis of moist desquamation scores alone showed a decrease in both the mean and peak RISRAS scores (38% (p=0.04); 46% (p=0.02) respectively) in favour of the Mepilex Lite dressings. Exit questionnaires highlighted that the silicon dressing was easy to use and comfortable to wear and most patients preferred the dressings over the cream. The findings of this thesis demonstrates that Mepilex Lite dressings reduce the visible signs of radiation-induced acute skin reactions and cause a substantial decrease in patient discomfort and subjective symptoms.