Kidney transplant recipients and sun exposure

Abstract

Non-melanoma skin cancers induced by solar radiation are the most frequent types of cancers in humans and their incidence is increasing worldwide. Ultraviolet radiation (UV) is a major environmental cause. The individual risk of skin cancer is due both to the total cumulative exposure to UV radiation and to sporadic patterns of sun exposure as during free time. Organ transplant recipients have a relative risk of developing squamous cell carcinoma 100-fold higher than healthy subjects, whereas the risk of developing basal cell carcinoma is increased by 10. Beside the direct effect on keratinocyte DNA, UV radiations have also a negative effect on the local immunosurveillance in the exposed areas and on systemic immunity. Educational programs on sun exposure for organ transplant recipients recommend to limit the time of exposure and to apply sunscreen creams. Sunscreen creams are topical preparations that attenuate the effects of UV radiation on the skin. Recently the safety of sunscreen creams is a matter of discussion because of the toxicological studies performed on chemical filters. The majority of chemical filters absorb through the skin, then into the blood. T-shirts, hats and sunglasses provide full protection from UV rays. Body areas (face, neck, ears and décolleté) exposed to solar radiation can be efficiently protected applying a blend of mineral powders (clays, bentonite, kaolin, montmorillonite) formulated to reflect sunrays. The use of mineral powders as sunscreens is encouraged also for dialysed subjects and for patients with autoimmune diseases.