Development of Malignancy Following Living Donor Kidney Transplantation M. Nafar, B. Einollahi, K. Hemati, F. Poor Reza Gholi, and A. Firouzan ABSTRACT Background. Malignancy following renal transplantation is an important medical prob- lem during the long-term follow-up. We studied some features of the cancers that developed in our patients. Methods. We retrospectively reviewed all patients who underwent renal transplantation and developed malignancy from July 1984 to July 2004. Results. The 2117 patients who underwent living donor kidney transplantation during the 19-year period had a mean follow-up of 81.1  61 months. During the follow-up, 38 patients (1.8%) developed cancer: 14 Kaposi’s sarcomas, 11 lymphoproliferative diseases, four squamous cell carcinomas of the skin, two basal cell carcinomas, one breast, one ovary, one melanoma, one seminoma, one lung, and one ovary. Mean age at transplanta- tion in the malignancy cases was higher than the other recipients (43.5  12.1 vs 32  13.9 years) (P = .000). A Kaposi’s sarcoma occurred earlier compared with the other cancers (23  22 vs 62  44 months P  .05); most of these patients were over 40 years at transplantation (P  .05). We also observed that patients treated with mycophenolate mofetil developed cancer earlier than the others (19 vs 52 months; P = .001). None of the cases with lymphoma had a history of antilymphocytic agent therapy. The 10-year patient survival was 73%. Conclusion. The prevalence of cancer (1.8%) was among the lowest compared with other studies possibly due to implementing a living donor kidney transplantation program that required a low frequency of induction therapy. O NE SERIOUS COMPLICATION in kidney trans- plantation is the development of malignancy, the risk is approximately 100 times greater than the general popu- lation. 1–3 This high incidence has been attributed to the use of immunosuppressive agents to prevent allograft rejection. Neoplasms showing increased frequency in this group in- clude: skin cancer [mostly squamous cell carcinoma (SCC) but also basal cell carcinoma (BCC), melanoma, and mer- kel cell cancer], non-Hodgkin’s lymphoma (NHL), Kaposi’s sarcoma (KS), in situ carcinoma of the uterine cervix, anogenital cancer, renal cell carcinoma, hepatocellular car- cinoma, and a variety of sarcoma. 1,4–6 In contrast, the incidence of the most common solid tumors in the general population—lung, prostate, colorectal, and invasive uterine carcinoma—is not increased in renal transplant recipi- ents 7,8 with the possible exception of colorectal cancer after more than 10 years. Other differences between cancers in the general population and in recipients include: SCCs in kidney transplanted patient are more aggressive and more likely to recur after resection. 9 –11 NHLs in recipients are high grade and mostly of B-cell origin. 8 Extranodal involve- ment is also common, occurring at the rate of 70%. 8,12 Central nervous system involvement is a frequent compli- cation of NHL in recipients (20% to 25%), although it is infrequent in the general population. 8,13 The prevalence rate of posttransplant malignancies dif- fers between geographical areas; for example, in Europe the rate is 1.6% and in Australia, 24%. This difference is due to the prevalence of skin cancers in these areas. The From the Urology/Nephrology Research Center, Shaheed Labbafinejad Medical Center, Shaheed Beheshti University of Medical Sciences, Tehran, Iran. Address reprint requests to Mohsen Nafar, Shaheed Lab- bafinejad Medical Center, 9th Boustan, Pasdaran, Tehran 1666679951, Iran. E-mail: nafarm@hbi.or.ir © 2005 by Elsevier Inc. All rights reserved. 0041-1345/05/$–see front matter 360 Park Avenue South, New York, NY 10010-1710 doi:10.1016/j.transproceed.2005.08.011 Transplantation Proceedings, 37, 3065–3067 (2005) 3065