Basic aspects of the pathogenesis and prevention of non-melanoma skin cancer in solid organ transplant recipients: a review.

INTRODUCTION: As numbers of transplant recipients and survival rates increase, the vulnerability of this population to several malignancies also rises. Non-melanoma skin cancer (NMSC) carries the highest rates of morbidity and mortality in this population. To avoid these malignancies, it is necessary to identify particular risk factors in transplant recipients and to follow preventive protocols.

METHODS: The MEDLINE and EMBASE databases were reviewed using as keywords the medical subject headings (MeSH) "transplantation", "skin neoplasm" and "prevention". The search was limited to clinical trials, randomized clinical trials and case-control studies conducted during the previous 20 years.

RESULTS: The most important risk factors for the development of NMSCs in the transplant recipient population are cumulative ultraviolet radiation exposure, use of immunosuppressive agents (especially azathioprine as a photosensitizing agent) and infections by human papillomaviruses. The use of sun protection and retinoids were identified as possible protective factors. Other potential therapies, such as antioxidants, difluormethylornithine and cyclooxygenase-2 inhibitors, require further study.

CONCLUSIONS: Patient risk factors for the development of NMSC should be reviewed during the transplant consultation. Individuals found to be at increased risk should undergo closer follow-up and preventive care counseling. This article proposes an algorithm for the prevention of NMSC.