Incidence of postrenal transplantation malignancies: a report of two centers in Tehran, Iran

Oncogenic Virus Infections in the General Population and End-stage Renal Disease Patients With Special Emphasis on Kaposi's Sarcoma Associated Herpes Virus (KSHV) in Northeast of Iran

BACKGROUND

Globally, almost 20% of cancers are related to infectious agents that can be prevented. Oncogenicity refers to viruses that may cause cancers, more importantly in immunocompromised subjects such as transplant and hemodialysis patients. Therefore, epidemiological studies are the first line for understanding the importance of these agents in public health, particularly, in mobile populations, tourism and pilgrimage regions.

OBJECTIVES

Oncogenic viral infections, such as hepatitis B virus (HBV), hepatitis C virus (HCV) and Epstein-barr virus (EBV) are the most common viral agents in immunocompromised patients. Furthermore, human T lymphocyte virus type I (HTLV-I), due to endemicity in Khorasan Razavi province located northeast of Iran as a pilgrimage region, and Kaposi's sarcoma associated herpes virus (KSHV), as an oncogenic herpesvirus in immunocompromised subjects have been investigated among the general population and those with end-stage renal diseases (ESRD).

PATIENTS AND METHODS

A cross-sectional study was carried out among 1227 randomly selected individuals; 25 donors and 195 patients with ESRD, including 60 kidney transplant recipients and 135 dialysis patients from the Khorasan Razavi province, Iran. Serological tests were carried out using commercial enzyme-immunoassay kits. To confirm positive serology tests, the extracted viral DNA or RNA was examined for the presence of KSHV, HTLV-I and HCV by conventional PCR.

RESULTS

The prevalence of KSHV infection in the general population was 1.71% (21/1227); 2.60% (10/384) males and 1.30% (11/843) females. In kidney transplants, viral infections occurred in 23.3% of subjects; including EBV, HTLV-I and HBV-HCV co-infection in 8.3%, 3.3% and 1.7%, respectively. In patients on hemodialysis, viral infections were present in 29.6% including EBV, HTLV-I and HBV-HCV co-infection in 2.2%, 5.9% and 16.3%, respectively. Seroprevalence of KSHV in patients with kidney transplants was 1.7% and in patients on dialysis was 3.0%. Furthermore, KSHV and HTLV-I genome was detected in 25% and 100% of seropositive subjects, respectively.

CONCLUSIONS

In conclusion, this study demonstrated that these tumor virus infections including HTLV-I, KSHV and particularly hepatitis viruses (HBV plus HCV) are prevalent in the general population and in patients on hemodialysis, which might be an important health concern in this region due to the mobile population.

Seroprevalence of Human herpesvirus 8 (HHV-8) and incidence of Kaposi's sarcoma in Iran

Seroepidemiological surveys show that the prevalence of human herpesvirus 8 (HHV-8) infection mostly varies in various geographical areas and reflects the local incidence of classic and endemic KS, being widespread in sub-Saharan Africa and Mediterranean countries and uncommon in the USA and Northern Europe. In the Middle East only few populations, such as Ashkenazi and Sephardic groups in Israel, have been adequately evaluated for HHV-8 seroprevalence. Among Iranian population a striking higher seroprevalence of HHV8 has been reported among haemodialysis (16.9%), renal transplant recipients (25%) and HIV (45.7%) patients compared to blood donors (2%). Kaposi's sarcoma (KS) is the rarest cancer in Iran, with an annual age-standardized incidence varying from 0.10 to 0.17 per 100,000 in males and from 0.06 to 0.08 per 100,000 in females. KS, however, is one of the most important malignancies in Iranian renal transplanted patients affecting up to 2.4% of organ recipients. The epidemiology of HHV8 and KS in Iran needs further evaluation. While the high prevalence of HHV-8 antibodies in HIV positive and haemodialysis individuals may be attributed to high-risk sexual behavior and polytransfusions, respectively, unknown determinants may be responsible for high seroprevalence of HHV8 and high incidence of KS in solid organ recipients. A global survey on HHV8 seroprevalence in Iran is mandatory to define co-factors associated with HHV8 infection and KS risk in the general Iranian population and in specific patient groups.

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.

Posttransplantation lymphoproliferative disorders in renal transplant recipients: report of over 20 years of experience

INTRODUCTION

Despite the benefits of immunosuppressive medications to improve graft function, they have several adverse effects, such as development of neoplasms in renal transplant recipients. Posttransplantation lymphoproliferative disorders (PTLDs) are not uncommon complications, so we conducted a study to evaluate the characteristics of affected patients.

METHODS

We enrolled 2117 kidney recipients from June 1984 to March 2004 in order to find pathological and clinical evidence of neoplasms. We collected and analyzed all data on PTLD patients.

RESULTS

Overall there were 46 recipients with different types of neoplasms, among which the most common types were diseases of the skin (24 cases, 52.2%), Kaposi's sarcoma (15 cases, 32.6%), and PTLD (14 cases, 30.4%). The mean (+/- SD) age of PTLD patients at the time of transplantation was 37.86 +/- 9.67 years and 42.8% were women. Median and mean (+/- SD) time interval to PTLD diagnosis were 38.5 and 50.35 +/- 41.7 months, respectively (range 1 to 146 months). Types of PTLD in these patients were kidney lymphoma (14.3%); gastrointestinal (14.3%); brain lymphoma; tonsils; palatine; Hodgkin's lymphoma, large cell lymphoma, and acute lymphoblastic lymphoma (each 7.1%), with 28.6% unspecified types. The 1-, 5-, and 10-year patient survival rates after transplantation were 71.4%, 51.4%, and 44.3%, respectively. Despite discontinuing immunosuppressive therapy in PTLD patients, five of six surviving had graft function up to a mean time of 105.4 +/- 57.6 months after transplantation.

CONCLUSION

Our findings showed that the prevalence of PTLD was 0.66%, which was less than reports from Western countries. The fact that there were surviving grafts for a considerable time despite discontinuing immunosuppressive therapy is of great importance.

Outcome of Kaposi’s Sarcoma and Graft Following Discontinuation of Immunosuppressive Drugs in Renal Transplant Recipients

PURPOSE

Owing to the use of immunosuppressive drugs, renal transplant recipients are at risk for malignancies including Kaposi's sarcoma (KS). Following the diagnosis, physicians tend to decrease the doses of immunosuppressive drugs to lower tumor progression rate. On the other hand, those who receive lower doses of immunosuppressive drugs are at a higher risk for acute rejection. In this study, we evaluated the outcome of KS on renal allografts following discontinuation or decrease in the doses of drugs.

METHODS

Since 1984, 14 (nine men and five women) among 2000 cases of renal transplantation have been diagnosed as KS. In 11 patients, cyclosporine was completely discontinued, the dosage was decreased to half of the initial dose in other cases. Except one case, we discontinued either azathioprine or mycophenolate mofetil.

RESULTS

During 57 months of follow-up on average, the serum creatinine level remained normal in 10 but increased in four cases. Kidney function deteriorated in two of these four patients at the beginning of study. Three patients died with normal serum creatinine levels. Discontinuation of immunosuppressive drugs caused complete remission of KS in all patients except one who received chemotherapy.

CONCLUSION

Discontinuation of immunosuppressants following the diagnosis of KS caused complete remission of this cancer in almost all patients and seemed to be relatively safe for kidney graft function.