Incidence and Prediction of Nonmelanoma Skin Cancer Post-renal Transplantation: a Prospective Study in Queensland, Australia

Background: Nonmelanoma skin cancer (NMSC) is a significant clinical problem after renal transplantation, particularly in areas of high UV light exposure. A single-center prospective study of a population of Queensland renal transplant recipients was performed with the aims of: (1) establishing NMSC incidence and tumor accrual post-renal transplantation, and (2) developing a clinically derived predictive index to identify transplant recipients at greatest risk.

Methods: Three hundred ten of 398 transplant recipients (78%) who underwent baseline assessment between July 1999 and April 2000 were reassessed a mean of 18 +/- 3.5 (SD) months later. A structured interview, full skin examination, biopsy of suspicious lesions, and review of medical and pathological records were used to determine the number and types of NMSC arising between the two assessments. Incidence (percentage of the population developing NMSC per year) and tumor accrual (number of tumors per person per year) were calculated. A clinically derived predictive index was generated using stepwise logistic regression models.

Results: Overall NMSC incidence was 28.1% and increased with duration of immunosuppression therapy: 18.8%, 24.8%, 33.3%, and 47.1% at less than 5, 5 to 10, 10 to 20, and greater than 20 years of immunosuppression therapy, respectively. Mean NMSC accrual was 1.85 +/- 3.84 tumors/person/y, increasing to 3.35 +/- 4.29 tumors/person/y after 20 years of immunosuppression therapy. Renal transplant recipients were stratified into categories of high and low NMSC risk by using predictive indices.

Conclusion: Clinically derived predictive indices can allow NMSC risk stratification of an Australian transplant population and may provide an evidence-based and cost-effective approach to developing a targeted clinical NMSC surveillance program.