Kaposi sarcoma in renal transplant recipients

Donor-derived human herpes virus 8-related Kaposi's sarcoma in renal allograft ureter

We present a case of human herpes virus 8 (HHV8)-associated Kaposi sarcoma (KS) occurring in a renal allograft ureter from a male donor. The female patient presented with a rising creatinine due to ureteric obstruction, and subsequent histological examination of the excised tumor revealed a KS. The tumor tested positive for HHV8 antigen and, using in situ hybridization to identify X and Y chromosomes, we were able to demonstrate that the tumor was of male origin. In the absence of any other KS lesions, this suggested that the tumor arose due to reactivation of latent HHV8 in the donor tissue, permitted by the recipient's immunosuppression. The patient was managed by a gradual reduction in immunosuppression and there has been no subsequent recurrence of the tumor. KS in renal transplantation is discussed in detail including the possible utility of pre-transplant HHV8 screening.

Skin cancer in renal allograft recipients - experience in different ethnic groups residing in the same geographical region

Cancer is a recognized long-term complication of kidney transplantation. Skin cancer is the most common post-transplant malignancy in developed countries but information is limited on the nature of skin cancer in allograft recipients from developing countries followed up over an extended period. The records of all patients (n = 542) who had received kidney transplants (n = 623) at our institution over a 23-yr period were reviewed and those with skin cancer were identified. Demographic, clinical, and pathologic details were collected. After a mean follow up of 6.3 yr 11 (5.9%) white patients had skin cancer of whom nine (82%) were male. No non-whites had skin cancer. In white patients skin cancer accounted for 68% of all post-transplant malignancies. Squamous cell carcinoma was the most common malignant skin lesion and 84% of all lesions occurred in sun-exposed areas. Specific immunosuppression did not appear to influence the number of lesions or the interval from transplantation to cancer development. Patients responded well to treatment with no mortality related to the skin cancer. Skin cancer is relatively unique to patients of European origin.

Racial and ethnic variations in incidence and pattern of malignancies after kidney transplantation

Malignancies are a well-recognized complication of renal transplantation. Although the problem is well studied in developed countries, less is known about it in developing countries. Although geographic and ethnic variations have been alluded to in several reports, to our knowledge the subject has not been investigated formally. From April 1976 through March 1999, 41 (7.6%) patients were diagnosed with cancer among a heterogeneous population of renal allograft recipients treated at our institution in Cape Town, South Africa. The incidence of malignancies was comparable in white and nonwhite patients. However, squamous cell cancer and basal cell cancer of the skin (in that order) were the most common cancers in white patients, in whom they occurred exclusively. On the other hand, Kaposi sarcoma was the most common cancer in nonwhite renal allograft recipients, in whom it accounted for almost 80% of all cancers. Review of the world literature suggests that posttransplant cancers are less common in developing countries; Kaposi sarcoma is the most common lesion, with few exceptions. Malignant lymphomas are also more common in developing countries. The impact of different immunosuppressive regimens is controversial. In general, cyclosporine is not associated with a significant increase in the incidence of cancer after renal transplantation, although the time to the first cancer may be reduced. In our experience, the pattern of posttransplant cancers in white and nonwhite patients living in the same geographic region epitomizes the world experience of the disease and suggests that genetic factors, rather than geography, are the more important determinants of cancer development after renal transplantation.