Epithelial skin cancers after kidney transplantation: a retrospective single-centre study of 376 recipients

Post-transplant non-melanoma skin cancers (NMSC) are the most common malignancies in kidney transplant recipients. To analyse risk factors associated with the occurrence of basal cell carcinomas (BBC) and squamous cell carcinomas (SCC) in kidney transplant recipients. Statistical analysis was performed on 376 kidney transplant recipients screened for NMSC in 2002-2009 and followed until 2013. NMSC developed in 23.67% of individuals with an SCC/BCC ratio of 2.15:1 and an age-standardised incidence ratio (IR) of 2.71 cases (95% CI: 1.97-3.46) per 100 patients/year. Based on multivariable analysis, NMSC occurrence significantly correlated with higher age (p<0.001), fair skin type (p = 0.01), and particularly SCCs with male gender (p = 0.001). Patients with >10 actinic keratoses were at higher risk of developing NMSCs (IRR = 2.95; 95% CI: 1.97-4.42; p<0.001) and more prone to SCCs, compared to BCCs (p = 0.04). Also, more SCC carriers had high counts of warty lesions (p = 0.006). Calcineurin inhibitors were associated with higher NMSC incidence (IRR = 2.81; 95% CI: 1.1-7.01; p = 0.03), while no difference was seen with the mammalian target of rapamycin (mTOR) inhibitors. Our results confirm an influence of the individual immunosuppressive regimen, in addition to the duration of immunosuppression, and suggest that older patients, males, fair skinned recipients or those affected with high counts of actinic keratoses (field cancerisation) are particularly prone to development of NMSC.