Skin cancer after solid organ transplantation.

Sir, We read the article by Belloni-Fortina et al. (1) with great interest. This retrospective study focused on the incidence of, and risk factors for, skin complications among liver transplant patients. They concluded that in these recipients the risk of premalignant and malignant skin lesions was lower than that of other solid organ transplants. Although organ transplant recipients are predisposed to the development of skin cancers, the epidemiology of skin tumours following organ transplantation varies geographically (2, 3); therefore, the lower rate of skin cancer in the study of Belloni-Fortina et al. (1) may reflect geographical differences. We have previously reported on the low rate of skin tumours among Iranian kidney transplant patients (2, 3). The overall incidence of skin tumors in 11,255 kidney transplant recipients was 1.14%, representing half of all post-transplant malignancies (128 out of 245 cases) (2). Kaposi’s sarcoma was the most common tumour type (2, 3); the incidence of Kaposi’s sarcoma is greatly increased among transplant patients in the Middle East countries (4, 5). Belloni-Fortina et al. (1) showed that male sex (maleto-female ratio of 6:1) and advanced age increased the risk of skin tumours after liver transplantation. In our study, male recipients also had more skin cancers (male:female ratio of 2.5:1), and individuals older than 45 years were at higher risk (odds ratio 3.8) (2). Although Belloni-Fortina et al. (1) found azathioprine as a second immunosuppressant was not a risk factor for the development of skin cancer, we observed that recipients who were on azathioprine were more likely to develop skin tumours when compared with those treated with mycophenolate mofetil (odds ratio 2.9) (2). In conclusion, the types of skin tumours following organ transplantation vary geographically, and the incidence and risk factors for these tumours appear to differ be tween countries.