Clinical risk factors associated with nonmelanoma skin cancer in renal transplant recipients.

A single-center, cross-sectional, longitudinal study was conducted to determine the prevalence, annual incidence, and clinical risk factors for skin cancer in a white renal transplant population. One hundred eighty-two white patients (95% of population) with functioning allografts, a mean age at transplantation of 38.9 +/- 15. 6 (SD) years, and a mean follow-up of 8.5 +/- 6.3 years were interviewed and examined between May 1997 and June 1999. All case notes were carefully reviewed. Since transplantation, 16.5% of the patients had developed nonmelanoma skin cancer; 15.4%, actinic keratoses (AK); 53%, viral warts; and 1.6%, lentigo maligna melanoma (n = 3). Thirty-nine percent of the tumors were detected as a consequence of this study, and 20% of these occurred on covered body sites. The squamous cell (SCC)-basal cell carcinoma (BCC) ratio was 3.8:1. Eighty-two percent of the patients were examined a second time 12 months after the initial assessment. Using these data to identify new lesions, the annual incidence was calculated at 6.5%, increasing to 10.5% at more than 10 years posttransplantation. Duration of immunosuppression, older age at transplantation, presence of AK, male sex, and outdoor occupation were significantly associated with both SCC and BCC; SCC alone was associated with a history of having smoked tobacco. Early identification of those at greatest risk using a clinical risk profile may allow the development of more structured preventative and surveillance strategies than currently exist.