title: Retinoids in the chemoprevention of non-melanoma skin cancers: why, when and how.
abstract: BACKGROUND
  The chemoprevention refers to the use of various types of chemical agents for preventing carcinogenic progression. Systemic retinoids are the most studied chemopreventive agents due to their capacity to regulate cell proliferation and their demonstrated efficacy in several clinical studies.
  
  
  OBJECTIVE
  The aim of the authors was to give precise indications regarding the use of the systemic retinoid in the chemoprevention of non-melanoma skin cancer (NMSC).
  
  
  METHODS
  The authors reviewed the literature found through a search to MEDLINE (from 2001 to December 2011).
  
  
  RESULTS
  Both acitretin and isotretinoin are effective for the prevention of NMSC. Isotretinoin is preferred in xeroderma pigmentosum and nevoid basal cell carcinoma syndrome, whereas acitretin is more used in transplant recipients, psoriasis and severe sun damage.
  
  
  CONCLUSIONS
  Despite numerous studies of the literature concerning retinoids in chemoprevention of NMSC, precise details of the type of retinoid to use, dosage and the duration of this preventive treatment and how to manage side effects in the case of long-lasting treatment are still not uniform and comparable. Moreover, neither guidelines nor approval by Food and Drug Administration exist to regulate the use of retinoids in chemoprevention.
authors.affiliation: Department of Clinical and Experimental Medicine, Section of Dermatology, University of Ferrara, Ferrara, Italy. vincenzo.bettoli@gmail.it
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Bettoli
authors.forename: Stefania
authors.initials: S
authors.lastname: Zauli
authors.forename: Anna
authors.initials: A
authors.lastname: Virgili
mesh_terms: D017255:Acitretin / Q000009:adverse effects / Q000494:pharmacology / Q000627:therapeutic use*; D001478:Basal Cell Nevus Syndrome / Q000188:drug therapy / Q000517:prevention & control; D003879:Dermatologic Agents / Q000009:adverse effects / Q000494:pharmacology / Q000627:therapeutic use*; D006801:Humans; D015474:Isotretinoin / Q000009:adverse effects / Q000494:pharmacology / Q000627:therapeutic use*; D056687:Off-Label Use; D016377:Organ Transplantation; D011565:Psoriasis / Q000150:complications; D012307:Risk Factors; D012878:Skin Neoplasms / Q000139:chemically induced / Q000188:drug therapy / Q000517:prevention & control*; D013472:Sunlight / Q000009:adverse effects; D014983:Xeroderma Pigmentosum / Q000188:drug therapy / Q000517:prevention & control
chemical_list: D003879:Dermatologic Agents; D015474:Isotretinoin; D017255:Acitretin