title: Basic aspects of the pathogenesis and prevention of non-melanoma skin cancer in solid organ transplant recipients: a review.
abstract: BACKGROUND
  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.
authors.affiliation: Organ and Tissue Transplant Group, Department of Surgery, Faculty of Medicine, Universidad Nacional de Colombia, Bogotá, Colombia.
authors.forename: Héctor C
authors.initials: HC
authors.lastname: Perez
authors.affiliation: Organ and Tissue Transplant Group, Department of Surgery, Faculty of Medicine, Universidad Nacional de Colombia, Bogotá, Colombia.
authors.forename: Xiomara
authors.initials: X
authors.lastname: Benavides
authors.affiliation: Fundación Universitaria de Ciencias de la Salud, Bogotá, Colombia.
authors.forename: Juan S
authors.initials: JS
authors.lastname: Perez
authors.affiliation: Organ and Tissue Transplant Group, Department of Surgery, Faculty of Medicine, Universidad Nacional de Colombia, Bogotá, Colombia.
authors.forename: Maria A
authors.initials: MA
authors.lastname: Pabon
authors.affiliation: St Joseph Dermpath Center, Houston, TX, USA.
authors.forename: Jaime
authors.initials: J
authors.lastname: Tschen
authors.affiliation: Organ and Tissue Transplant Group, Department of Surgery, Faculty of Medicine, Universidad Nacional de Colombia, Bogotá, Colombia.
authors.forename: Silvia J
authors.initials: SJ
authors.lastname: Maradei-Anaya
authors.affiliation: Organ and Tissue Transplant Group, Department of Surgery, Faculty of Medicine, Universidad Nacional de Colombia, Bogotá, Colombia.
authors.forename: Luis
authors.initials: L
authors.lastname: Lopez
authors.affiliation: Organ and Tissue Transplant Group, Department of Surgery, Faculty of Medicine, Universidad Nacional de Colombia, Bogotá, Colombia.|Organ Transplantation Division, Hospital Universitario San Ignacio, Bogotá, Colombia.
authors.forename: Eyner
authors.initials: E
authors.lastname: Lozano
mesh_terms: D002280:Basal Cell Carcinoma / Q000453:epidemiology / Q000276:immunology / Q000517:prevention & control*; D002294:Carcinoma, Squamous Cell / Q000453:epidemiology / Q000276:immunology / Q000517:prevention & control*; D018890:Chemoprevention; D006801:Humans; D007165:Immunosuppression Therapy / Q000009:adverse effects*; D007166:Immunosuppressive Agents / Q000009:adverse effects; D016377:Organ Transplantation; D065840:Protective Factors; D012307:Risk Factors; D012878:Skin Neoplasms / Q000453:epidemiology / Q000276:immunology / Q000517:prevention & control*; D013472:Sunlight / Q000009:adverse effects
chemical_list: D007166:Immunosuppressive Agents