Measurement of breast skin viscoelasticity and a pilot study on the potential radioprotective effect of a zinc-based cream.

Radiation-induced late skin effects were studied in patients with breast cancer in relation to different protocols of fractionated radiotherapy in three different medical centres, in Israel, the UK and the USA. The mechanical properties of skin were evaluated in breasts of healthy volunteers, and non-irradiated and irradiated breasts of patients, using a newly developed viscoelasticity skin analyser (VESA). The increase of the dose of radiation per fraction was found to have more impact on the development of radiation-induced late skin effects than the elevation of the total dose given. In addition, a pilot study on the possible radioprotective effect of external application of a cream containing zinc oxide on radiation-induced early skin changes in patients with breast cancer was initiated. Non-invasive measurement of trace elements and zinc pharmacokinetics in the skin of healthy controls following the application of the zinc oxide cream were performed by unique diagnostic X-ray spectrometry (DXS). Application of the cream, followed by thorough skin cleansing, significantly increased the amount of residual zinc in the skin, but continuous daily treatment did not cause further build-up of the dermal zinc level. The radioprotective effect of the zinc oxide cream on the skin is now being studied.