Abstract
Sun exposure, the main source of ultraviolet radiation exposure, is the major environmental risk factor for skin cancers, both melanoma and non-melanoma. The impact of exposure can be dramatically reduced by practicing sun protection behaviors. Still, recommendations for sunlight exposure are an area of controversy, as sun avoidance and sun protection practices may lead to inadequate vitamin D levels. This duality is particularly relevant to childhood cancer survivors, who are particularly vulnerable both to the hazardous effects of ultraviolet radiation and to deleterious skeletal and extra-skeletal effects of vitamin D deficiency. These patients are at high risk for developing non-melanoma skin cancer and therefore are firmly advised to avoid or minimize sun exposure and adopt skin protection measures. On the other hand, several studies showed an inverse association between regional UV-B radiation exposure and cancer mortality, with activation of vitamin D-related pathways by sun exposure proposed as the likely mechanism. A protective role for vitamin D in the prevention of and recovery from malignancies has been suggested by observational studies, by clinical trials showing reduced cancer incidence with vitamin D supplementation, and by laboratory studies demonstrating that the physiologically active form of vitamin D, 1;25(OH)2D3 has anti-cancerous effects. In this respect, it is worrisome that a number of studies demonstrated sub-optimal 25OHD levels in children and adolescents with a history of malignancy. Regarding sun habits of this population, there is very limited information in the literature comparing sun protection behaviors of childhood cancer survivors to individuals without a history of cancer. Three studies in adult survivors of childhood cancer showed inconsistent results. Only three previous studies investigated this issue in children and adolescents, showing that patients spent less time outside compared to controls, however adherence to sun protection recommendations was incomplete. Similar findings were recently observed by our group. We conclude that more attention should be paid to improve sun protection habits of survivors of childhood cancer throughout their lives. At the same time, since sunlight avoidance may result in vitamin D insufficiency and might have deleterious implications for bone health and possibly on cancer survival, dietary interventions to optimize intake of vitamin D may be required.
Original language | English |
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Title of host publication | Sun Exposure |
Subtitle of host publication | Risk Factors, Protection Practices and Health Effects |
Publisher | Nova Science Publishers, Inc. |
Pages | 69-92 |
Number of pages | 24 |
ISBN (Electronic) | 9781634820882 |
ISBN (Print) | 9781634820875 |
State | Published - 1 Jan 2015 |
Externally published | Yes |