Topical corticosteroid therapy for acute radiation dermatitis: a prospective, randomized, double-blind study.

BACKGROUND: Radiation dermatitis is a common side-effect of radiation therapy, but there is no current consensus about its appropriate therapy. OBJECTIVES: To compare treatment with topical 0.1% methylprednisolone vs. 0.5% dexpanthenol in a cohort of patients undergoing fractionated radiation therapy for breast cancer. METHODS: In a randomized, double-blind design, treatment was initiated at the beginning of radiation therapy and continued for 2 weeks after termination of radiation. Outcomes were compared by three different measures: clinical (symptom score), functional (transepidermal water loss, TEWL) and subjective (quality of life, QOL). RESULTS: In a preliminary cohort of untreated patients undergoing radiation therapy, clinical signs and TEWL levels increased progressively during radiation therapy, reaching highest values at 5 and 4 weeks, respectively. Although neither topical treatment reduced the incidence of radiation dermatitis, both delayed the emergence of greatest clinical and TEWL scores until approximately 6 and 5 weeks, respectively. With topical corticosteroids, clinical symptoms and TEWL were less pronounced than with dexpanthenol. Whereas general QOL improved after completion of radiation therapy, skin-related QOL declined. However, the skin-related QOL decline could be at least in part reversed by use of topical corticosteroid vs. dexpanthenol-containing emollient. CONCLUSIONS: We provide evidence that prophylactic and ongoing use of topical therapy with either topical corticosteroid or a dexpanthenol-containing emollient ameliorates, but does not prevent radiation dermatitis. Our data suggest, but do not prove, a benefit of a topical corticosteroid vs. a dexpanthenol-containing emollient. Further controlled studies with larger cohorts will be needed to determine optimal forms of topical therapy for radiation dermatitis.

Permeability barrier function of skin exposed to ionizing radiation.

OBJECTIVE: To characterize the epidermal permeability barrier function of skin during exposure to ionizing radiation. DESIGN: A prospective cohort study. SETTING: University hospital medical center. PATIENTS: Fifteen women receiving local radiation therapy (5000-6000 rad [50-60 Gy]) following breast-conserving surgery for breast cancer. MAIN OUTCOME MEASURES: Clinical symptoms and transepidermal water loss (TEWL). RESULTS: Epidermal permeability barrier function is impaired in patients who exhibit clinical signs of radiation dermatitis. The functional damage to the stratum corneum induced by ionizing radiation occurs with a delayed course, starting within a mean period of 11 days and reaching maximal values after a mean period of 27 days (range, 13-75 days). The onset of TEWL increase precedes the onset of radiation dermatitis and the maximal TEWL measurements precede the peak of skin changes. Patients with an early onset of TEWL increase show a longer duration of skin symptoms. CONCLUSIONS: Skin changes caused by radiation dermatitis are associated with an increase in TEWL. The barrier impairment is comparable to the changes observed with UV radiation exposure but exhibits an even more delayed course. Our results suggest that preservation of the epidermal permeability barrier function by topical treatment may ameliorate radiation dermatitis.