Background: The increased incidence of skin cancers in transplant patients is well documented; however, few data exist on the risk of subsequent skin tumors in a given patient after the first skin cancer. The aim of this study was to compare the individual rate of subsequent skin cancers in kidney (KTR) and heart transplant recipients (HTR) after the first squamous cell carcinoma (SCC) and to assess risk factors for tumor multiplicity.
Methods: In all, 188 patients (121 KTR/67 HTR) were studied for up to 5 years. The cumulative number of SCC, basal cell carcinomas, Bowen's diseases, premalignant keratoses, and keratoacanthomas was recorded yearly after the first SCC.
Results: Overall, 71% of patients developed 757 new skin tumors. At 5 years, 100% of HTR and 88% of KTR had presented new tumors. However, the mean number of all tumors was significantly higher in KTR (3.4 vs. 2.0, 4.8 vs. 2.6, 6.6 vs. 2.9, 8.5 vs. 3.5, and 9.7 vs. 4.6 at 1, 2, 3, 4, and 5 years, respectively). Transplantation before 1984, multiple tumors at first consultation, eye and hair color, and skin type were predictive of multiple tumors. Early minimization of immunosuppression and of sun exposure tended to be associated with a reduced rate of all tumors and of SCC, respectively.
Conclusions: Although the proportion of HTR developing new tumors is greater as compared with KTR, the mean number of tumors per patient is higher in KTR. This could be due to a longer immunosuppression in patients younger at transplantation.