title: Permeability barrier function of skin exposed to ionizing radiation.
abstract: OBJECTIVE
  To characterize the epidermal permeability barrier function of skin during exposure to ionizing radiation.
  
  
  METHODS
  A prospective cohort study.
  
  
  METHODS
  University hospital medical center.
  
  
  METHODS
  Fifteen women receiving local radiation therapy (5000-6000 rad [50-60 Gy]) following breast-conserving surgery for breast cancer.
  
  
  METHODS
  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.
authors.affiliation: Department of Dermatology, University of Innsbruck, Anichstrasse 35, A-6020 Innsbruck, Austria. matthias.schmuth@uibk.ac.at
authors.forename: M
authors.initials: M
authors.lastname: Schmuth
authors.forename: A
authors.initials: A
authors.lastname: Sztankay
authors.forename: G
authors.initials: G
authors.lastname: Weinlich
authors.forename: D M
authors.initials: DM
authors.lastname: Linder
authors.forename: M A
authors.initials: MA
authors.lastname: Wimmer
authors.forename: P O
authors.initials: PO
authors.lastname: Fritsch
authors.forename: E
authors.initials: E
authors.lastname: Fritsch
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D008875:Middle Aged; D010539:Permeability / Q000528:radiation effects; D011446:Prospective Studies; D011855:Radiodermatitis / Q000175:diagnosis / Q000209:etiology; D012867:Skin / Q000528:radiation effects*; D012879:Skin Physiological Phenomena / Q000528:radiation effects*; D013997:Time Factors