Cancer in patients on dialysis for end-stage renal disease: an international collaborative study

CKD as a risk factor for bladder recurrence after nephroureterectomy for upper urinary tract urothelial carcinoma

BACKGROUND

The aim of this study is to examine chronic kidney disease (CKD) as a risk factor for bladder recurrence and cancer-specific and total mortality in a cohort of patients with upper urinary tract (UUT) urothelial carcinoma (UC) treated by means of nephroureterectomy.

STUDY DESIGN

Cohort study.

SETTINGS & PARTICIPANTS

150 patients with primary UC of the ureter or renal pelvis treated by means of nephroureterectomy at a single center.

PREDICTOR

Presence and severity of CKD according to preoperative markers of kidney damage, estimated glomerular filtration rate calculated using the Modification of Diet in Renal Disease Study equation, and other covariates.

OUTCOMES & MEASUREMENTS

Subsequent bladder recurrences, cancer-specific survival, and overall survival.

RESULTS

Of 150 patients, 37 (25%) had no CKD, 71 patients (47%) had CKD stages 1 to 4, and 42 patients (28%) had CKD stage 5. 41 (27%) and 31 patients (21%) reported exposure to herbal medicine or tobacco use, respectively. During a mean follow-up of 4 years, 53 patients (35%) developed bladder recurrence and 27 (18%) died, of whom 14 (9.3%) died of cancer. Overall 5-year bladder recurrence-free and cancer-specific survival rates were 62% and 89%, respectively (n = 150). Risks of bladder recurrence were 2.43 (95% confidence interval, 1.00 to 5.93) and 3.95 (95% confidence interval, 1.59 to 9.80), greater in patients with CKD stages 1 to 4 and CKD stage 5 compared with patients without CKD, respectively. Ureteral involvement of the primary tumor (hazard ratio, 1.97; 95% confidence interval, 1.12 to 3.48) also was associated significantly with an increased rate of bladder recurrence. The risk of death from all causes or UC was not significantly greater in patients with CKD stages 1 to 4 or CKD stage 5 compared with those without CKD. Higher tumor stage (pT2 to 4) was associated significantly with overall death (hazard ratio, 5.15; 95% confidence interval, 1.84 to 14.48).

LIMITATIONS

A retrospective study in an area of high incidence of both UUT-UC and CKD.

CONCLUSIONS

Advancing CKD stage of patients and positive ureteral involvement of the primary tumor (especially in the lower ureter) are associated with greater risk of subsequent bladder recurrence in patients with UUT-UC treated by means of radical surgery.

Malignant tumors following renal transplantation

A vese és egyéb szervek átültetését követően, többek között a korszerű immunszuppresszív kezelés eredményeként a betegek túlélési ideje egyre növekszik. Ugyanakkor a tartós immunszuppresszió hátrányos következménye, hogy a túlélési idővel arányosan növekszik a rosszindulatú daganatok kialakulásának a valószínűsége is. A fokozott daganatos kockázatért elsősorban az elnyomott immunrendszer tumor- és vírusellenes funkciójának károsodása felelős. A poszttranszplantációs daganatok gyakorisága átlagosan 2–4-szerese a nem transzplantált lakosságénak, és összetétele is eltér a populációra jellemző tumorokétól. Elsősorban azok a daganatok gyakoriak, melyek kialakulásában fontos szerepet tulajdonítunk az onkogén vírusoknak (bőrrák, lymphoma, Kaposi-szarkóma, szájüregi rák, anogenitalis régió tumorai stb.). A szervátültetés utáni daganatok kezelhetősége és prognózisa rosszabb, mint a lakosság hasonló daganataié. A poszttranszplantációs tumorok növekvő gyakoriságuk miatt a transzplantált betegek hosszú távú sorsának egyre fontosabb meghatározó tényezőjévé kezdenek válni. A daganatos kockázat csökkentését segítheti a karcinogén hatások kerülése, a rákmegelőző állapotok és a tumorok korai felismerése és kezelése, az alacsony dózisú immunszuppresszív kezelés, valamint az onkológiai szempontból kedvezőbb hatású, a sejtproliferáció gátlásával ható immunszuppresszív vegyületek alkalmazása.

Hepatitis C virus infection and the dialysis patient

Hepatitis C virus (HCV) remains common in patients undergoing regular dialysis and is an important cause of liver disease in this population both during dialysis and after renal transplantation (RT). Anti-HCV screening of blood products has almost eliminated posttransfusion HCV infection but acquisition of HCV continues to occur in dialysis patients because of nosocomial spread. The natural history of HCV in dialysis population is not completely understood though recent data show that HCV infection has a detrimental role on survival of chronic dialysis patients. Several clinical trials have suggested that the response rate to conventional interferon (IFN) is higher in dialysis patients than those with normal kidney function but tolerance is lower. There are only limited data about pegylated IFN alone or in association with ribavirin for hepatitis C in dialysis population. IFN remains contraindicated post-RT because of concern about precipitating graft dysfunction; however, preliminary evidence shows the durability of sustained response to antiviral therapy pre-RT after renal transplant. Successful pretransplant therapy is associated with several benefits after RT including reduced incidence of posttransplant diabetes mellitus and de novo glomerulonephritis in HCV-infected recipients.

Pyrexia of unknown origin (PUO) in a hemodialysis patient

Patients with end stage renal disease (ESRD) are predisposed to malignancy. A patient who presented with a persisting fever, episodically above 38 degrees C, of unknown origin is described. The diagnosis of the illness remained elusive, over repeated hospital admissions and comprehensive investigations for over 11 weeks, until her last admission when the patient finally represented with features of acute liver cell failure and succumbed shortly afterwards. A liver biopsy revealed high grade lymphoma, an uncommon presentation for lymphoma. While malignancy is increased in dialysis patients, lymphoma is a relatively uncommon malignancy described. This case is a rare incidence of diffuse Non-Hodgkin's Lymphoma (NHL) isolated to the liver, causing fever, liver cell failure and death in a hemodialysis patient.

Treatment of HCV in patients with renal failure

There continues to be a high prevalence of hepatitis C virus infection in patients with chronic kidney disease (CKD) on maintenance hemodialysis, despite screening of blood products and precautions to prevent the transmission of viral hepatitis within dialysis units. In addition, an increased rate of mortality from liver disease has been observed in infected patients on long-term dialysis, despite the frequent absence of biochemical dysfunction. Hepatitis C-infected renal transplant recipients have diminished patient and graft survivals compared to uninfected controls. Treatment with interferon in renal transplant candidates has resulted in sustained viral responses that have been long lasting even after subsequent renal transplant. A major concern limiting the use of interferon following renal transplant is graft dysfunction due to rejection. Ribavirin's induction of hemolytic anemia is the major reason why it is avoided in patients with CKD. Cautious use of reduced-dose ribavirin in small studies has been promising in these patients with close monitoring of hematocrit and additional measures to enhance compensatory erythropoiesis.

Renal transplantation in patients with Balkan endemic nephropathy

BACKGROUND

Balkan endemic nephropathy (BEN) is a chronic tubulointerstitial disease prevalent in Croatia, Romania, Bulgaria, Bosnia and Herzegovina, and Serbia. In addition to renal disease, an increased incidence of upper urothelial carcinomas (UUCs) has been observed in the foci of BEN. Carcinoma may occur alone or in combination with BEN. Immunosuppression is associated with an increased risk for development of different malignancies. There are no data in the literature about the outcome of patients with BEN after transplantation.

METHODS

We performed a retrospective evaluation of the database and review of the charts and pathology reports of 601 renal transplant recipients treated at our institution.

RESULTS

From January 1995 to December 2004, kidney transplantations were performed in nine patients with BEN. One-year graft survival was 100%. A man, who was transplanted in 1997 died 2 years after transplantation with a functioning graft due to disseminated cancer from the pelvis of his own kidney. A female patient developed UCC 2 years after transplantation. They were both treated with a bolus of methylprednisolone before transplantation, because of four HLA-mismatches. A male patient developed UCC in the native and transplanted kidneys. He underwent a native nephroureterectomy with partial nephroureterectomy of transplanted kidney. His graft function was preserved with decreased immunosuppression. Three years later a urinary bladder carcinoma was discovered on a regularly performed multislice computed tomography. One patient developed a skin malignancy. Other patients have had uneventful posttransplantation courses with excellent graft function. Thus, 33.3% of patients with BEN developed UUC, compared with a 0.67% prevalence of urinary tract tumors among transplanted patients with other causes of end-stage renal disease.

CONCLUSION

Patients with BEN are at increased risk for the development of UCC after transplantation. Regular screening for early detection of malignancy is mandatory. Longer follow-up and results from other transplant centers are needed to further investigate the relationship between BEN and UCC after renal transplantation.

Gastrectomy for patients with gastric cancer and non-uremic renal failure

AIM: To investigate the safety and outcome of gastrectomy for patients with gastric cancer and non-uremic renal failure (NURF).

METHODS: One hundred forty-seven patients who underwent gastrectomy for carcinoma were retrospectively divided into two groups: a group with Ccr values of ≥ 50 mL/min (Group 1; n = 110), and one with Ccr values of ≥ 20 to < 50 mL/min (Group 2; n = 37). Preoperative patient characteristics, intraoperative parameters (including operation time and blood loss), and postoperative management and complications were evaluated.

RESULTS: There were no statistically significant differences between the two groups in operation time (297.9 min vs 272.6 min, P = 0.137) or blood loss (435 mL vs 428 mL, P = 0.078). The differences in postoperative complications and hospital stay between the groups were not statistically significant. None of the patients in Group 2 required dialysis therapy, and no patients died due to gastrectomy or gastrectomy-related causes. The overall 4-year survival rates in Groups 1 and 2 were 86.6% and 81.8%, respectively (P = 0.48), and the corresponding 4-year disease-free survival rates for stageI, II, and III patients were 88.7% and 83.5%, respectively (P = 0.65).

CONCLUSION: Gastrectomy can be performed as safely in patients with NURF similar to patients with normal renal function.

Comparison of stage at diagnosis of cancer in patients who are on dialysis versus the general population

BACKGROUND AND OBJECTIVES

Frequent medical encounters in patients with ESRD on dialysis may allow early detection of malignancies despite low rates of cancer screening in this population. It is therefore unclear whether dialysis patients are disadvantaged in terms of cancer diagnosis. This study compared stage at diagnosis of cancer in a population-based sample of patients with ESRD versus the general population.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

The Surveillance, Epidemiology, and End Results Medicare database was used to identify patients with ESRD and incident cancers from 1992 through 1999. Modified Poisson regression models were used to predict nonlocalized stage of cancer at diagnosis in patients with ESRD versus the general population, adjusting for demographics, cancer site, region, year of diagnosis, and comorbidity. Two general population comparisons were used: Standardized Surveillance, Epidemiology, and End Results public-use data and Medicare control subjects without ESRD matched 3:1 to patients with ESRD.

RESULTS

A total of 1629 patients with ESRD and incident cancer were identified. Overall, the likelihood of nonlocalized stage at diagnosis was not significantly different for patients with ESRD versus the standardized Surveillance, Epidemiology, and End Results general population or matched Medicare control subjects. Stratifying by cancer site, colorectal cancers were significantly more likely to be diagnosed earlier in the ESRD group, whereas prostate cancers were significantly more likely to be diagnosed at a later stage.

CONCLUSIONS

With the exception of prostate cancer, patients with ESRD are not more likely to present with later stage malignancies compared with the general population.

Immunosuppressive therapy and malignancy in organ transplant recipients: a systematic review

Post-transplant malignancy is recognised as being a major limitation to the success of solid organ transplantation and it is currently considered one of the unavoidable costs of long-term immunosuppressive therapy. However, the continual introduction of new immunosuppressive drugs and the growing knowledge about their different oncogenic profiles, requires a continuous evaluation of the available evidence on this topic. The incidence and risk of malignancy is elevated in solid organ transplant recipients compared with the general population. As proof of the relationship between immunosuppressive therapy and post-transplant malignancy, epidemiological data reveal that the length of exposure to immunosuppressive therapy and the intensity of therapy are clearly related to the post-transplant risk of malignancy, and that once cancer has developed, more intense immunosuppression can translate into more aggressive tumour progression in terms of accelerated growth and metastasis and lower patient survival. The association between malignancy and immunosuppressive therapy is mediated through several pathogenic factors. Indirectly, immunosuppressive drugs greatly increase the post-transplant risk of malignancy by impairing cancer surveillance and facilitating the action of oncogenic viruses. However, the direct pro- and anti-oncogenic actions of immunosuppressants also play an important role. The cancer-promoting effect of calcineurin inhibitors, independently of depressed immunosurveillance, has been demonstrated in recent years, and currently only mammalian target of rapamycin (mTOR) inhibitors have shown simultaneous immunosuppressive and antitumour properties. Reports of the initial results of the reduced incidence of cancer in organ transplant recipients receiving mTOR inhibitor therapy strongly indicate separate pathways for pharmacological immunosuppression and oncogenesis. The role of mTOR inhibitors has been firmly established for the treatment of post-transplant Kaposi's sarcoma and its role in the management of patients with other post-transplant malignancies should be clarified as soon as possible. Prevention of morbidity and mortality resulting from post-transplant malignancy should become a main endpoint in solid organ transplant programmes, and the choice and management of immunosuppressive therapy in each phase of transplantation plays a central role in this objective. Although comprehensive and rigorous information about the management of immunosuppressive therapy in transplant recipients at risk of or affected by cancer is still lacking, new experimental and clinical data about mTOR inhibitors offers novel approaches to this problem.

Gefitinib administration in a patient with lung cancer undergoing hemodialysis

Gefitinib is mainly metabolized by the liver and its excretion is mostly in bile excrements. However, the feasibility of gefitinib in patients with chronic renal failure undergoing hemodialysis has not, so far, been reported. A 58-year-old woman with chronic renal failure due to polycystic kidney disease, undergoing hemodialysis, experienced diplopia due to meningitis carcinomatosa by lung adenocarcinoma. Sequencing analysis of her tumor tissue revealed deletion of 15 nucleotides in E746-A750 of exon 19. She started daily administration of 250mg gefitinib with hemodialysis three times a week. Her pharmacokinetic pattern after gefitinib administration was similar to those in patients with normal renal function and 88.7% of gefitinib was kept in the plasma through hemodialysis. Her symptoms and signs of meningitis carcinomatosa on brain magnetic resonance images improved. Thirteen months later, the meningitis got worse again and she stopped gefitinib administration. During gefitinib administration, there were no signs of adverse events. In summary, gefitinib is not eliminated by hemodialysis and was safely administered to a patient with non-small cell lung cancer and chronic renal failure who was undergoing hemodialysis.

Screening for prostate cancer using prostate-specific antigen testing in Japanese men on hemodialysis

OBJECTIVES

The objectives of this study were to evaluate the usefulness of serum prostate-specific antigen (PSA) screening in detecting prostate cancer in Japanese men on hemodialysis, and to analyze features of prostate cancer detected in these patients.

MATERIALS AND METHODS

This study included 115 male hemodialysis patients aged > 55 years who agreed to the measurement of serum PSA value (group A) and 7529 men aged > 55 years participating in a PSA mass screening test in Kobe City (group B) between April 2005 and March 2006. Prostate biopsy was recommended in men with serum PSA > 4.0 ng/ml in both groups. Seventy-eight patients with normal renal function aged > 55 years diagnosed as having prostate cancer during the same time period as groups A and B were also included as a comparison group (group C).

RESULTS

There was no significant difference in the distribution of serum PSA values between groups A and B. Prostate biopsy was performed in 8 and 205 men in groups A and B, respectively, and prostate cancer was detected in 5 and 68 in groups A and B, respectively; that is, there was no significant difference in the rate of positive prostate biopsy between these two groups (group A, 62.5%; group B, 33.2%), while the cancer detection rate in group A (4.3%) was significantly greater than that in group B (0.90%). In addition, there was no evident metastasis in five patients on hemodialysis who were diagnosed as having prostate cancer, and their serum PSA, clinical T stage and biopsy Gleason score were similar to those in group C. However, the percent of positive biopsy cores in these five was significantly greater than that in group C. All five were treated by maximal androgen blockade therapy, and all are currently alive without emergence of hormone-refractory diseases.

CONCLUSIONS

These findings indicate that hemodialysis patients may have an increased risk of prostate cancer, and that prostate cancer detected in such patients tends to be relatively advanced. Therefore, it would be recommended for hemodialysis patients to undergo PSA testing to screen for prostate cancer.

Decreased antigen-specific T-cell proliferation by moDC among hepatitis B vaccine non-responders on haemodialysis

Patients with end-stage kidney disease, whether or not on renal replacement therapy, have an impaired immune system. This is clinically manifested by a large percentage of patients unresponsive to the standard vaccination procedure for hepatitis B virus (HBV). In this study, the immune response to HBV vaccination is related to the in vitro function of monocyte-derived dendritic cells (moDC). We demonstrate that mature moDC from nonresponders to HBV vaccination have a less mature phenotype, compared to responders and healthy volunteers, although this did not affect their allostimulatory capacity. However, proliferation of autologous T cells in the presence of tetanus toxoid and candida antigen was decreased in non-responders. Also, HLA-matched CD4+ hsp65-specific human T-cell clones showed markedly decreased proliferation in the group of non-responders. Our results indicate that impairment of moDC to stimulate antigen-specific T cells provides an explanation for the clinical immunodeficiency of patients with end-stage kidney disease.

Risk factors for malignancy in Japanese renal transplant recipients

BACKGROUND

Among recipients of renal transplants, the incidences of renal cancer and gastrointestinal cancer are higher and that of skin cancer is much lower in Japan than in Europe and North America.

METHODS

The risk factors for the development of malignant tumors were examined in Japanese recipients of renal transplants. A total of 556 patients underwent renal transplantation at the Department of Urology, Osaka University Faculty of Medicine between March 1, 1965, and April 31, 2004. Of these patients, 366 were retrospectively studied in whom risk factors potentially related to the development of malignancy could be evaluated on the basis of medical records. The incidence of malignancy, survival rate, and risk factors for malignancy were examined.

RESULTS

The overall incidence of malignancy was 6.8% (25/366 patients). Six of the 25 patients with malignancy died of cancer, but there was no correlation between the occurrence of malignancy and the survival rate (P = .8058, log-rank test). A Cox proportional-hazards model identified treatment with tacrolimus (hazard ratio [HR] = 4.376; 95% confidence interval [CI]: 1.647-11.627; P = .0031) and age at transplantation (HR = 1.562; 95% CI: 1.089-2.240; P = .0155) as risk factors for malignancy.

CONCLUSIONS

The results of multivariate analysis suggested that age at transplantation and the use of tacrolimus were independent risk factors for the development of malignancy in recipients of renal transplants.

Prostate Cancer Screening with Prostate-Specific Antigen in Hemodialysis Patients

BACKGROUND/AIMS

The diagnostic validity of prostate-specific antigen (PSA) among men receiving hemodialysis (HD) has not been well defined. The aim of this study was to evaluate PSA levels in HD men and to compare them with those of non-uremic controls.

METHODS

PSA levels were measured in 620 HD men (40-89 years old, mean age 62.4 years). In patients with PSA >4.1 ng/ml, prostate biopsies were performed. Cancer-free men were defined as having PSA ranging between 0 and 4.0 ng/ml, or PSA >4.1 ng/ml but with a pathologically negative biopsy. The resulting data was compared with that for 3,636 non-uremic controls (55-59- (n = 468), 60-69- (n = 2,220), and 70-79-year-old men (n = 948)).

RESULTS

Of 45 HD men with PSA >4.1 ng/ml, 22 consented to undergo a biopsy. Ten were positive and 12 were negative. The mean PSA of cancer-free HD men of 50-59 (n = 159), 60-69 (n = 214), 70-79 (n = 116), and 80-89 (n = 30) were 1.0, 1.0, 1.3, and 2.1 ng/ml, respectively. Cancer-free HD men demonstrated significantly lower PSA compared to controls.

CONCLUSIONS

HD men had lower PSA levels than those of controls.

Oxidative stress and DNA hypermethylation status in renal cell carcinoma arising in patients on dialysis

Renal cell carcinoma (RCC) is more frequently observed in patients on dialysis than in patients with normal renal function. However, the mechanism underlying carcinogenesis in RCC patients on dialysis is still unclear. We hypothesized that oxidative stress affects patients on dialysis and generates new neoplasms, and therefore analysed the correlation between the influences of various markers of oxidative stress and carcinogenesis in those patients. We evaluated the immunohistochemical expression of oxidative stress markers, such as iNOS, 8-OHdG, and COX-2 in 42 cases on dialysis and 51 cases with normal renal function as a control. The methylation status of p16INK4a, p14ARF, VHL, and RASSF1A was analysed together with clinicopathological factors. Histologically, the papillary type was observed more frequently in dialysis RCC than in sporadic RCC. Immunohistochemically, overexpression of iNOS (p < 0.0001) and COX-2 (p = 0.0002) was more frequently observed in dialysis RCC. Furthermore, the 8-OHdG labelling index was significantly higher in dialysis RCC than in sporadic RCC. Hypermethylation of p16INK4a was more frequently found in dialysis RCC (p < 0.05). However, no significant correlations between oxidative stress markers and DNA hypermethylation status were observed. The overexpression of iNOS, COX-2, and 8-OHdG in dialysis RCC suggests that patients on dialysis are affected by oxidative stress and that this effect plays an important role in the genesis of dialysis RCC.

Screening, diagnosis, and treatment of cancer in long-term dialysis patients

Some have suggested that the American Cancer Society guidelines for cancer screening be applied to patients who are on long-term dialysis and have used cancer screening as a means of assessing delivered preventive health care to patients with ESRD. However, cancer screening is effective only when it leads to survival benefit (usually expressed as days of life saved) without incurring high financial costs. Certain cancers such as human papillomavirus-associated cervical and tongue cancer and urologic malignancies are more common among dialysis patients, yet because the expected remaining lifetime of most dialysis patients is shorter than the time lived to develop malignancy, cancer screening in dialysis patients as applied to the general population is ineffective from the perspective of both cost and survival benefit. Cancer screening in dialysis patients is therefore best provided in an individual patient-focused manner. The occurrence, diagnosis, and treatment of cancer as well as issues related to cancer screening in dialysis patients are discussed.

Effect of hemodialysis on serum complexed prostate-specific antigen levels

OBJECTIVE

The measurement of prostate-specific antigen (PSA) is a useful tool in the screening and follow-up of prostate cancer, but its diagnostic validity is uncertain in hemodialysis patients. The aim of this study was to evaluate the effects of hemodialysis on serum complexed PSA (cPSA) levels.

MATERIAL AND METHODS

A total of 36 men (mean age 62.54+/-8.20 years) with end-stage renal disease were enrolled in a prospective study. Serum total PSA (tPSA), free PSA (fPSA) and cPSA, and hematocrit levels were measured before and immediately after dialysis using low-flux membranes in the serum and in the dialysis ultrafiltrate.

RESULTS

After hemodialysis, cPSA, fPSA and the fPSA:tPSA ratio increased significantly (p<0.05). However, there was no significant increase in tPSA. fPSA, cPSA and tPSA were not detected in ultrafiltrate. Hematocrit levels increased significantly (p<0.0001) due to hemoconcentration. Of patients with initial serum tPSA and cPSA values and fPSA:tPSA ratios below the cut-off values, none had a post-hemodialysis value greater than the cut-off point. There were weak correlation between the difference in values after and before hemodialysis of hematocrit and cPSA (p=0.035), and between the percentage change in levels before and after hemodialysis of hematocrit and cPSA (p=0.041).

CONCLUSIONS

Hemodialysis induced elevations in all forms of PSA, but tPSA was the least affected form. cPSA did not show any diagnostic superiority over other forms of PSA. Thus, serum tPSA remains a reliable parameter for follow-up of prostate cancer in uremic patients receiving long-term dialysis. However, further research is needed to explain the pathophysiology of alterations in the concentrations of different forms of PSA.

The janus face of immunosuppression - de novo malignancy after renal transplantation: the experience of the Transplantation Center Munich

After decades of successful organ transplantation clinicians continue to be troubled by the increasing incidence of cancers under maintenance immunosuppression. In this study, we examined rates of malignancies in 2419 renal transplant recipients transplanted in our institution between 1978 and 2005. In renal transplant recipients the cumulative incidence of cancer after 25 years was 49.3% for all tumors and 39.7% excluding non-melanoma skin cancers, compared with 21% for a normal sex- and age-matched population. The most frequent tumors observed were non-melanoma skin cancers (20.5%), kidney cancers (12.0%), and cancers of the pharynx, larynx, or oral cavity (8.2%). The general increase of cancer risk was 4.3-fold. Independent risk factors for the development of a tumor were male gender, older recipient age, the presence of preformed antibodies before transplantation, and the time on immunosuppression. Interestingly, the use of IL-2-receptor antagonists significantly reduced the tumor risk of transplant recipients. The tumor risk between immunosuppressive drugs typically used for maintenance immunosuppression was not significantly different. However, mammalian target of rapamycin (mTOR) inhibitor-based immunosuppressive protocols showed a clear tendency for lower malignancy rates. De novo malignancies following renal transplantation represent a serious problem endangering the prognosis of otherwise successfully transplanted patients. Future studies will have to address whether optimized immunosuppressive regimens including mTOR-inhibitors are capable of reducing the incidence or preventing the development of posttransplant malignancies.

Radiation safety protocol for high dose 131I therapy of thyroid carcinoma in patients on hemodialysis for chronic renal failure

Iodine ablation therapy for thyroid cancer on patients receiving dialysis poses unique radiation safety challenges. Exposure to gamma and beta negative particles by the hemodialysis (HD) staff is a concern that has not been well studied. A 53-y-old male patient on HD for chronic renal failure was scheduled for 131I high dose therapy as treatment for thyroid papillary carcinoma. The patient was on HD every other day, prior to ablation. A high dose of 131I (3,607.5 MBq) was required. The patient was admitted for 131I therapy, and continued HD. Thyroid cancer ablation therapy was administered according to our institutional protocol. New radiation safety measures were developed and implemented in order to give the patient an optimal treatment dose, reduce radiation to the patient (critical organs and whole body), and to protect the HD personnel. This included placing two lead shields between the patient and the HD nurse, and HD monitoring by two alternating nurses to reduce their radiation exposure. Film badges were used to measure radiation exposure to the nursing staff. Dosimetry calculations were obtained to determine radiation absorbed doses by the optic lens, skin, and whole body. Quality control verification for this shielding arrangement proved to be effective in protecting the HD staff against gamma and beta negative radiation from recent 131I high dose therapy. Implementation of this model proved to be an effective and adequate radiation safety protocol for limiting radiation exposure to the HD staff. The patient was given 3607.5 MBq for optimal treatment after HD. Hemodialysis was repeated after approximately 48 and 96 h to remove excess 131I and reduce radiation to the patient.

Excess risk of cancer in renal transplant patients

Cancer data were reviewed in 488 patients who underwent renal transplantation and received cyclosporine at our centre from January 1985 to December 1995. Incidence of nonmelanoma skin cancer (NMSC) was standardized on the age and sex distribution of the French population. For cancer other than NMSC, we calculated the ratio of observed to expected numbers of cancer cases in the RT population, based on age- and sex-specific incidence for cancer in France. Standardized incidence ratios (SIR) were calculated for all cancers and for specific cancer types encountered. Over 4,638 patient-years of exposure, 51 (10.4%) transplant recipients developed a first NMSC which was significantly associated with older age at transplantation (P < 0.0001) and the 1991-1995 transplantation period (P = 0.0008). Fifty-six recipients developed cancer other than NMSC over the period. The SIR for all cancer was 2.2 (1.5-3.0) in males and 3.0 (1.9-4.6) in females. The SIR for specific cancer types revealed significant excess for native kidneys [13.0 (5.2-26.8)] prostate cancer [3.6 (1.5-3.0)] and post-transplant lymphoproliferative disorder (PTLD) [9.5 (3.1-22.1)] in males, and cervical cancer [25.3 (9.3-55.0)], native kidneys [26.4 (5.4-77.2)] and PTLD [28.9 (9.4-67.6)] in females. Incidence of NMSC and some types of other cancer is high in cyclosporine-treated patients. Optimizing monitoring practice might be useful to identify subjects with significant excess risk for specific types of solid tumours.

Genomic Damage and Malignancy in End-Stage Renal Failure: Do Advanced Glycation End Products Contribute?

In end-stage renal disease (ESRD) there is not only excessive morbidity and mortality due to cardiovascular disease but also an enhanced occurrence of various types of cancer. Both are characterized by oxidative stress and inflammation as two of the central underlying causes of the disease states. In cancer, genomic damage has been demonstrated to be of high pathogenetic relevance. DNA lesions may induce mutations of oncogenes and tumor-suppressor genes which, in the long-run, may lead to malignancies if mutagenicity is not mitigated by repair mechanisms. A high incidence of genomic damage in ESRD patients has been validated by various biomarkers of DNA lesions. We reviewed the mechanisms of DNA damage, focusing in particular on the role of advanced glycation end products (AGEs) which accumulate markedly in renal insufficiency. Considering the in vitro and in vivo findings to date, one has to assume a significant role of AGEs in DNA damage and the potential development of cancer.

Mass screening for prostate cancer in patients with end-stage renal disease: a comparative study

OBJECTIVE

To determine the usefulness of prostate-specific antigen (PSA) screening for prostate cancer in patients with end-stage renal disease (ESRD), as although serum PSA is effective in the early detection of this cancer in the general population, there are few reports of its utility in patients with ESRD.

PATIENTS AND METHODS

Blood samples were obtained for PSA screening from April 2002 to September 2003; 1250 men with ESRD aged >50 years were compared with 1007 healthy control men aged >55 years, all in Kumamoto Prefecture, Japan. All men with a serum PSA level of >4.0 ng/mL were categorized as PSA-positive and were further assessed, including a prostate biopsy.

RESULTS

There was a statistically significantly greater increase in PSA level with age in the ESRD group than in the healthy controls. The rate of cancer detection among men with a PSA level of >10 ng/mL was significantly higher in patients with ESRD than in healthy controls. Thirteen patients with ESRD and five healthy control men were finally diagnosed with prostate cancer.

CONCLUSION

The serum PSA level was slightly higher and the incidence of prostate cancer at higher PSA levels appeared to be greater in men with ESRD than in healthy controls. The findings of this large study suggest that PSA screening is useful for the diagnosis of prostate cancer in these patients.

Predictive Value of a Positive Fecal Occult Blood Test Increases as the Severity of CKD Worsens

BACKGROUND

Because chronic kidney disease (CKD) may be associated with gastrointestinal bleeding from trivial mucosal lesions, we hypothesized that the predictive value of a positive fecal occult blood test (FOBT) result for clinically important colonic lesions would decrease as the stage of CKD worsened.

METHODS

We prospectively identified 1,225 consecutive asymptomatic average-risk patients who were referred for colonoscopy to evaluate a positive FOBT result. Using the Modification of Diet in Renal Disease equation, we estimated glomerular filtration rate (GFR) and staged the severity of CKD by using standard criteria as follows: normal/stage 1 (GFR > or = 90 mL/min/1.73 m2 [> or = 1.50 mL/s]), stage 2/3 (GFR 30 to 89 mL/min/1.73 m2 [0.50 to 1.48 mL/s]), and stage 4/5 (GFR < 30 mL/min/1.73 m2 [< 0.50 mL/s] or dialysis).

RESULTS

Clinically important lesions were identified in 23.9% of 531 individuals with none/stage 1 CKD, 32.8% of 497 subjects with stage 2/3 CKD, and 42.6% of 197 patients with stage 4/5 CKD (P < 0.001). Compared with patients with none/stage 1 CKD, adjusted odds of identifying a clinically important lesion were 1.61 (95% confidence interval, 1.21 to 2.15) in subjects with stage 2/3 CKD and 2.33 (95% confidence interval, 1.62 to 3.36) in patients with stage 4/5 CKD. Prevalences of adenomas of 1 cm or greater (15.1% versus 20.1% versus 22.8%; P = 0.007), carcinomas (5.1% versus 10.1% versus 13.2%; P < 0.001), and vascular ectasias (1.7% versus 2.4% versus 6.1%; P = 0.003) increased with the severity of CKD.

CONCLUSION

Contrary to our initial hypothesis, we found that the predictive value of a positive FOBT result for clinically important colonic lesions increased as the severity of CKD worsened.

Genomic damage in chronic renal failure--potential therapeutic interventions

In end-stage renal failure, genomic damage is enhanced. This has been shown both in the predialysis and dialysis phase by various biomarkers, such as micronuclei frequency and single cell gel electrophoresis in lymphocytes as well as with 8-hydroxy-2'-deoxyguanosine in leukocytes. There are also data about mitochondrial DNA deletions and chromosomal abnormalities. Genomic damage may be induced by a multitude of toxic factors and mutagens, in particular via enhanced generation of reactive oxygen species. In in vitro studies, incubation of tubular cells with various AGEs (carboxymethyllysine-BSA, AGE-BSA, and methylglyoxal-BSA) and angiotensin II resulted in a marked DNA damage. Coincubation with various antioxidants as well as the angiotensin II receptor blocker, candesartan, suppressed the toxic action. Moreover, an improved uremic state by daily hemodialysis ameliorated the genomic damage in lymphocytes, as compared to patients on conventional hemodialysis.

HEMATOLOGY: ISSUES IN THE DIALYSIS PATIENT: Multiple Myeloma in End-Stage Renal Disease

Multiple myeloma is a common cause of chronic kidney disease (CKD). Patients with myeloma-related kidney disease but low levels of serum monoclonal proteins can be diagnosed with symptomatic myeloma in a simplified diagnostic classification. The presence and type of renal disease in myeloma is dependent on the light chain secreted. Treatment has recently changed and now includes the use of thalidomide and bisphosphonates. Thalidomide can cause hyperkalemia and bisphosphonates can cause renal failure in patients with CKD. Their use is not contraindicated, but they should be used with caution. High-dose melphalan with an autologous stem cell transplant is now the standard of care and should not be withheld from patients with CKD, even those on dialysis. This treatment can improve the renal disease, and this is more likely if treatment is started early. In patients with persistent dialysis dependence, renal transplantation can be performed if the patient has a complete remission.

Thyroid function and morphology after a successful kidney transplantation

Although thyroid disorders related to the end-stage renal disease (ESRD) are well known, there are discordant data on the function and morphology of the thyroid gland after renal transplantation (RT). The objective of this cross-sectional, case-control study was to investigate the prevalence and risk factors for disorders in the thyroid function and morphology after a successful RT. Fifty consecutive patients (25 females, 25 males) with fully functioning allograft were enrolled. Their age at transplant ranged from 23 to 44 yr (median, 38) and their post-RT follow-up lasted 15-86 months (median, 23). One hundred healthy subjects matched for sex, age and body mass index (BMI) were included as controls. Serum free thyroid hormones, TSH, thyroglobulin, thyroid hormone-binding globulin (TBG) and iodine urinary excretion were determined; ultrasonographic exam of the thyroid gland was performed in all subjects. Age, gender, time elapsed from RT, dialysis duration, kidney function, type of immunosuppression and corticosteroid dose were considered as possible influencing factors for the thyroid function. Hypothyroidism was found in 6% of patients, "low T3 syndrome" in 52%, while another 26% had free T3 (FT3), free T4 (FT4) and TSH in the lowest third of the normal range, suggesting inhibition of the whole hypothalamic-pituitary-thyroid (HPT) axis. Iodine excretion and prevalence of anti-thyroid antibodies were similar in both patients and controls. There was no significant difference in the thyroid function according to different immunosuppressive regimens. In patients, an ultrasonographic exam revealed a very variable thyroid volume ranging from 7.2 to 24.8 ml. Solid nodules were detected in 12 (24%) cases and cystic lesions in another four (8%); they were proven negative at cytological examination. Dialysis duration was longer in patients with thyroid nodules than in those without (p<0.05). Inhomogeneous hypoechoic pattern typical for chronic thyroiditis was more frequent than its biochemical expression. In conclusion, a high prevalence of abnormal thyroid morphology was found in patients after a successful RT, being partly related to a previous uremia. Abnormalities in the thyroid function are likely an expression of the post-transplant general and immunological conditions. Endocrinological follow-up is advisable in patients after RT, in order to discriminate thyroid dysfunctions which need specific treatments from those that can only be followed-up, avoiding inappropriate treatments of biochemical abnormalities.

Complete urinary tract extirpation: the University of Maryland experience

OBJECTIVES

Complete urinary tract extirpation (CUTE) involves simultaneous bilateral nephroureterectomy, cystectomy or cystoprostatectomy, and the creation of a urinary diversion, if needed. Case reports of this operation have been published, but to our knowledge, this is the largest case series yet reported. We sought to evaluate the characteristics and outcomes of patients who underwent CUTE.

METHODS

From 1994 to 2005, 9 patients underwent CUTE at our institution. We performed a retrospective chart review of these patients. The data reviewed included demographics, operative time, length of stay, complications, recurrences, and overall survival.

RESULTS

Nine patients who underwent CUTE were identified. The mean patient age at the operation was 61 years. Five patients were men. The mean operative time was 356 minutes. Two patients required a blood transfusion. The length of stay averaged 10.8 days (range 6 to 47). Four patients had functioning renal allografts before and after surgery. Three patients needing dialysis received renal allografts postoperatively. The overall survival rate at a mean follow-up of 31 months was 86%.

CONCLUSIONS

Although this report presented a small number of patients, it has illustrated that CUTE can be performed safely and allow definitive surgical treatment of patients with complex genitourinary pathologic findings.

The association of circulating leptin level with peripheral DNA damage in hemodialysis subjects

OBJECTIVES

Hemodialysis subjects have been shown to have both elevated serum leptin and peripheral DNA damage level, and leptin has been suggested to induce apoptotic features. Thus, in the present study, we aimed at finding out if there is any relationship between serum leptin level and peripheral DNA damage in hemodialysis subjects.

DESIGN AND METHODS

Forty hemodialysis subjects and 21 controls were included in the present study. Serum leptin level and peripheral DNA damage were assayed in all subjects enrolled in the study. Comet assay was used in determining DNA damage in peripheral lymphocyte.

RESULTS

Both serum leptin level and peripheral DNA damage were significantly higher in hemodialysis subjects than control (P<0.05 and P<0.001, respectively). Female subjects had significantly higher serum leptin level than male subjects in both hemodialysis and control group (both P<0.05). Significant correlation was observed between serum leptin level, and gender and body fat mass in both hemodialysis (P<0.05, beta=-0.637 and P<0.05, beta=0.386, respectively) and control group (P<0.05, beta=-0.569 and P<0.05, beta=-0.460, respectively). In hemodialysis subjects, peripheral DNA damage was significantly correlated with serum leptin level (P<0.05, beta=0.508).

CONCLUSION

In end-stage renal disease subjects, elevated serum leptin level seems to be associated with peripheral DNA damage and thus, may, in part, have a role in the development of DNA damage associated disorders.

Relation between Different Treatment Modalities and Genomic Damage of End-Stage Renal Failure Patients

BACKGROUND

Patients with end-stage renal disease display enhanced genomic damage. We investigated the relation between genomic damage and different treatment modalities.

METHODS

In a longitudinal study two groups of patients were analyzed in monthly intervals. We assessed the initiation of hemodialysis in 5 conservatively treated patients, and a switch from hemodialysis to hemodiafiltration in 7 patients. DNA damage was investigated in peripheral blood lymphocytes by micronucleus frequency and by comet assay analysis. With regard to potential genotoxicity of advanced glycation end products (AGEs), levels of imidazolone A and AGE-associated fluorescence (AGE-FL) were determined.

RESULTS

The initiation of hemodialysis did not alter the genomic damage. In patients who switched from hemodialysis to hemodiafiltration, a small but significant reduction in the comet assay but not in the micronucleus frequency was observed. Elevated plasma levels of imidazolone A and AGE-FL were not influenced by the treatment modalities.

CONCLUSION

In our small patient group no major reduction of the elevated genomic damage could be reached. Disease factors not influenced by altered dialysis modalities may have contributed considerably in our patient group. The persisting high levels of DNA damage suggest a need for further improvement. Inhibiting AGE formation may be one promising way for the future.

Accumulation of poly(ADP-ribose) polymerase inhibitors in children with chronic renal failure

Nicotinamide, N-methyl-2-pyridone-5-carboxamide (Met2PY) and N-methyl-4-pyridone-3-carboxamide (Met4PY) are biological metabolites of the intracellular coenzyme nicotinamide adenine dinucleotide (NAD) that can potentially inhibit poly(ADP-ribose) polymerase 1 (PARP-1; DNA repair enzyme). Our research was aimed at establishing whether chronic renal failure (CRF) in children leads to the elevation of plasma NAD metabolites sufficient to inhibit PARP-1 activity. Nicotinamide, Met2PY and Met4PY plasma and erythrocyte concentrations were measured in 25 children with CRF and in 19 healthy children. The effect of these NAD metabolites on PARP-1 activity was studied in vitro. We found that plasma concentration of all NAD metabolites (nicotinamide, Met2PY, Met4PY) in children with CRF could reach the concentration of 2, 30 and 10 microM as compared to 0.2, 1 and 0.5 microM, respectively, in healthy children. The concentration of nicotinamide metabolites correlated positively with plasma creatinine concentration and negatively with creatinine clearance in children with CRF. We found that Met2PY, Met4PY and nicotinamide inhibited in vitro PARP-1 activity with IC50 values of 2.1, 0.18 and 0.12 mM, respectively. Our data indicate that NAD metabolites accumulate in plasma of children with CRF and their combined effect could lead to the inhibition of PARP-1 activity. NAD metabolites could be particularly harmful in children due to higher DNA turnover than in adults.

N2-carboxyethyl-2′-deoxyguanosine, a DNA glycation marker, in kidneys and aortas of diabetic and uremic patients

Advanced glycation end product (AGE)-mediated modification of proteins is enhanced both in the kidneys and aortas of diabetic and uremic patients. However, AGE modification of deoxyribonucleic acid (DNA) has not yet been reported in these patients. We performed immunohistochemistry of kidneys and aortas using a monoclonal antibody against N(2)-carboxyethyl-2'-deoxyguanosine (CEdG), a marker of AGE-linked DNA. A total of 20 kidneys and 20 aortas were obtained by autopsy. The kidney samples consisted of two groups: nondiabetic nonkidney disease (control) and diabetic nephropathy. The aorta samples consisted of four groups: nondiabetic nonkidney disease (control), diabetes, hemodialysis, and diabetic hemodialysis. In the kidneys CEdG was detected predominantly in the nuclei of epithelial cells, mesangial cells, and endothelial cells of the glomeruli, parietal epithelial cells, and tubular cells. The number of CEdG-positive cells in the glomeruli was significantly increased in diabetic nephropathy compared with control. In the aortic walls, CEdG was detected predominantly in the nuclei of macrophages and myofibroblasts. The number of CEdG-positive cells in the aorta was significantly increased in hemodialysis patients and diabetic hemodialysis patients compared with control. The highest number of CEdG-positive cells in the aorta was observed in diabetic hemodialysis patients. In conclusion, AGE-mediated modification of DNA is enhanced in the kidney of diabetic nephropathy and the aorta of uremic atherosclerosis, and may induce a loss of genetic integrity in these diseases.

Urologische Betreuung von Patienten vor und nach Nierentransplantation

Patients with end-stage renal disease awaiting kidney transplantation require regular urological evaluation. The urologist's main task is early diagnosis and treatment of genitourinary malignancies and evaluation of the lower urinary tract. Furthermore, urologists are often confronted with the question of whether or not to perform pretransplant urological surgery, i.e., native nephrectomy for polycystic kidney disease. Urological care after kidney transplantation involves diagnosis and treatment of ureteral complications, malignancies, lower urinary tract symptoms, and last but not least erectile dysfunction, which has a prevalence of 20-50% among kidney transplant recipients. For the evaluation and follow-up of the living kidney donor, international guidelines have been developed in recent years to also help the urologist to perform a correct evaluation and follow-up of the kidney donor.

Selenium, the thyroid, and the endocrine system

Recent identification of new selenocysteine-containing proteins has revealed relationships between the two trace elements selenium (Se) and iodine and the hormone network. Several selenoproteins participate in the protection of thyrocytes from damage by H(2)O(2) produced for thyroid hormone biosynthesis. Iodothyronine deiodinases are selenoproteins contributing to systemic or local thyroid hormone homeostasis. The Se content in endocrine tissues (thyroid, adrenals, pituitary, testes, ovary) is higher than in many other organs. Nutritional Se depletion results in retention, whereas Se repletion is followed by a rapid accumulation of Se in endocrine tissues, reproductive organs, and the brain. Selenoproteins such as thioredoxin reductases constitute the link between the Se metabolism and the regulation of transcription by redox sensitive ligand-modulated nuclear hormone receptors. Hormones and growth factors regulate the expression of selenoproteins and, conversely, Se supply modulates hormone actions. Selenoproteins are involved in bone metabolism as well as functions of the endocrine pancreas and adrenal glands. Furthermore, spermatogenesis depends on adequate Se supply, whereas Se excess may impair ovarian function. Comparative analysis of the genomes of several life forms reveals that higher mammals contain a limited number of identical genes encoding newly detected selenocysteine-containing proteins.

Renal cell and transitional cell carcinoma in a Japanese population undergoing maintenance dialysis

PURPOSE

We verified differences in the incidence, clinical characteristics and outcomes between patients on chronic dialysis for end stage renal disease with renal cell carcinoma (RCC) and those with transitional cell carcinoma (TCC).

MATERIALS AND METHODS

Data regarding RCC and TCC were reviewed in the medical records of 6,201 patients with end stage renal disease who underwent chronic dialysis between January 1990 and June 2003 in our 38 affiliated dialysis centers, and data were compared with those reported in Australia and New Zealand.

RESULTS

Among the patients RCC developed in 38 (0.61%) and TCC developed in 16 (0.26%) during maintenance dialysis. The primary renal disease was chronic glomerulonephritis in patients with RCC (68.4%) and diabetic nephropathy in patients with TCC (43.8%, p = 0.002). Mean patient age at initiation of dialysis was 45 years for those with RCC and 63 for those with TCC (p < 0.001). Mean interval from dialysis induction to tumor diagnosis was 143 months for patients with RCC and 54 months for patients with TCC (p < 0.001). Of 38 RCCs 23 (60.5%) were incidentally detected by regular abdominal imaging examinations while painless gross hematuria was the cardinal symptom in 13 (81.2%) of 16 TCCs. Overall and cancer specific survivals after tumor diagnosis were significantly superior in patients with RCC compared to those with TCC (p = 0.0001 and p = 0.0003, respectively), and the cancer specific 5-year survival was 88.9% for RCC and 29.5% for TCC. In both cancers tumor stage significantly increased the risk of cancer specific death. Compared with patients from Australia and New Zealand, the incidence of RCC was higher and that of TCC was lower in our patients (p <0.001).

CONCLUSIONS

In the Japanese population on dialysis RCC is more common than TCC. Since long-term dialysis is a risk factor for RCC, regular imaging examinations may have contributed to the favorable outcome of our patients on dialysis with RCC. In contrast, the unfavorable outcome of TCC suggests the need for effective diagnostic measures for early detection of TCC in patients on dialysis.

Pulmonary Resection for Non-small-cell Lung Cancer in Patients on Hemodialysis: Clinical Outcome and Long-term Results

Patients on hemodialysis (HD) who undergo surgery represent a high risk group requiring careful perioperative management to avoid electrolyte imbalance and hemodynamic instability. The aim of the study was to analyze the postoperative outcome in terms of complications and survival of a group of patients on HD who had undergone pulmonary resection for non-small cell lung cancer (NSCLC). Six patients on HD underwent seven pulmonary resections at our institution from 1998 to 2003. The underlying kidney disease was nephrosclerosis in two patients and glomerulonephritis in four. The mean levels of blood urea nitrogen and serum creatinine were 107 +/- 11.5 mg/dl and 7.9 +/- 0.64 mg/dl, respectively. The mean preoperative PO2 and FEV1 were 77.6 +/- 2.4 mmHg and 2.4 +/- 0.16 liters, respectively. The histologic diagnosis was squamous cell carcinoma in four cases and adenocarcinoma in three. One patient underwent two lung resections in 4 years for two primary lung cancers. Five patients underwent lobectomy, one underwent a wedge resection, and in one case pneumonectomy was performed after neoadjuvant chemotherapy. There was no operative mortality. Postoperatively, atrial fibrillation occurred in two patients associated with sputum retention in both, and two other patients had hyperkalemia (complication rate 57%). One patient died of cardiac complications 27 months after surgery. The remaining five patients are currently alive with no evidence of disease. Patients on HD who undergo lung resection have a high rate of postoperative complications. Although the underlying disease influences long-term survival, radical lung resection in NSCLC patients is recommended in selected cases. Careful metabolic, hematologic, and pharmaceutical management is mandatory during the perioperative period.

Prevalence of cancer history prior to renal transplantation

Recurrent and de novo cancers contribute to morbidity and mortality post-transplantation. However, data on cancer prevalence in waiting list patients are lacking. The purpose of this study was to determine the prevalence of malignancy in patients considered for renal transplantation. Records of 382 potential renal transplant recipients were reviewed for the presence of malignant tumours. In 38 patients 45 tumours were detected. Forty-two malignancies were histologically confirmed, in three patients the evaluation was ongoing. Fourteen tumours were diagnosed before and 31 after initiation of dialysis. Overall cancer prevalence was 9.9%. For patients in the waiting list, the mean time from diagnosis of the malignancy was 2.2 years. Twenty of 45 (44%) tumours were located in the urinary system. The majority of malignancies was treated with a curative intention. Thus, 68% of patients with malignancies were listed as 'transplantable' or 'temporarily not transplantable'. From the waiting list, 13% were removed , 8% died and 11% had their evaluation halted because of their malignancy. Four patients received a transplant while eight patients died or were removed permanently from the list prior to transplantation. Death or removal from the list was as frequently related to tumour progression as to other causes (four patients each). A substantial number of waiting list patients had a history of malignancy. Future strategies have to identify patients at risk to assure intensive monitoring for recurrence, selection of patients who do not benefit from deferred transplantation and consideration of specific immunosuppressive protocols.

Mechanisms of the self/non-self-survey in the defense against cancer: Potential for chemoprevention?

When compared to a reference population, several large epidemiological studies with long-term follow-up have reported a three- to five-fold increased risk of neoplasia amongst patients who have received organ transplants, with an incidence curve that rises in a linear fashion with time. The relationship between the immune system and cancer is complex. The ability to discriminate "self" from "non-self" is one of the central roles of the immune system. Since tumors arise from transformation of host cells, it is not surprising that some aspects of tumor immunity resemble autoimmunity. The immune response to tumors shares aspects of both self- and non-self-immune recognition. What accounts for the apparent failure of immunity? In this review article, we address the role of the self/non-self-survey in the immune response to tumors, we describe mechanisms of immune surveillance against tumor cells, and we discuss models of ignorance, tolerance and tumor evasion of the immune response. The overall aim of the article is to demonstrate the scope for prevention of cancer in individuals at increased risk of developing malignancy due to immune compromise. Interventional strategies may involve the use of pro-differentiation agents such as retinoids, modifiers of polyamine biosynthesis or inhibitors of cyclooxygenase isozymes.

Cancer incidence after immunosuppressive treatment following kidney transplantation

Cancer incidence is increased in renal transplant recipients due to immunosuppressant treatment that should be maintained to prevent and treat acute rejection. Use of new and very potent immunosuppressants has made it possible to reduce acute rejection incidence and improve renal graft survival, although increase of infections and post-transplant neoplasms have become clearer. On the other hand, renal transplant candidates who remain on dialysis have a greater prevalence of neoplasms than the age-matched general population, either because the neoplasm was the cause of their renal failure (multiple myeloma or kidney or urinary tract cancers) or because their renal disease entails a risk for cancer development (acquired cystic disease or analgesic nephropathy). Practically, all de novo neoplasms have a greater incidence in renal transplant patients. Cutaneous neoplasms are the most prevalent in renal transplant recipients and their incidence increases with transplant time. Post-transplant lymphoproliferative diseases are more frequent in patients who receive greater immunosuppression (antithymocyte/antilymphocyte globulin or OKT3) or are infected de novo by Epstein Barr Virus (EBV) through the transplanted kidney. Kaposi's sarcoma has a high incidence in the renal transplanted population, does not appear in the general population, and is related with Human Herpes Virus 8 (HHV-8) infections. The incidence of tumors in non-functioning native kidneys is especially high in renal transplant due to the presence of acquired cystic disease or analgesic nephropathy. Gold standards of post-transplant de novo renal neoplasm prevention are modulating immunosuppression and avoiding exposure to sunlight and to different oncogenic viruses (EBV, cytomegalovirus, hepatitis B and C viruses).

Treatment of hepatitis C in potential kidney and heart transplant patients

Hepatitis C virus (HCV) is common in certain solid organ transplant recipients, most notably in those undergoing liver or kidney transplantation. Infection typically antedates transplantation but may have been acquired at the time of transplantation via infected blood products or organs. A more rapid and aggressive course of HCV-related infection and liver disease is the major concern in organ transplant recipients compared with immunocompetent patients. HCV-related liver disease is an important cause of morbidity and mortality in patients with end-stage renal disease treated by dialysis or transplantation. The outcome of HCV infection in renal and liver transplant recipients has been extensively investigated, whereas literature on HCV-related liver disease among patients with orthotopic heart transplantation is scanty. This article reviews the literature concerning the treatment of HCV-related liver disease in renal and orthotopic heart transplantation.

High iron storage levels are associated with increased DNA oxidative injury in patients on regular hemodialysis

BACKGROUND

Accumulating evidence suggests that oxidative stress is enhanced in patients on regular hemodialysis (HD). Iron supplementation is essential for the treatment of renal anemia, but there is a possibility that it could enhance oxidative stress by inducing the Fenton reaction. Here, we report our investigation of the relation between iron storage and DNA oxidative injury in HD patients.

METHODS

The study subjects were 48 patients on regular HD (age, 62.7 +/- 12.1 years; HD duration, 67.2 +/- 62.5 months; non-diabetic/diabetic; 22:26). Patients who were positive for hepatitis C virus antibody (HCV Ab), or hepatitis B surface antigen (HBsAg), and those with inflammatory or malignant diseases were excluded. The serum 8-hydroxy-2'-deoxyguanosine (8-OHdG) level, a marker of DNA oxidative injury, was measured before the first HD session of the week in all patients, and factors associated with high serum 8-OHdG were investigated. In 9 patients with a serum ferritin level of more than 1000 ng/ml at study entry, serum 8-OHdG levels were followed up for 6 months in the absence of iron supplementation.

RESULTS

Multivariate analysis showed that the serum ferritin level was a significant and independent determinant of serum 8-OHdG, and serum ferritin correlated significantly with the total dose of iron supplementation during the 6-month period of the study. In the nine patients, without iron supplementation, serum 8-OHdG levels, as well as serum ferritin, decreased significantly during follow-up.

CONCLUSIONS

Our results suggest that increased iron storage may induce DNA oxidative injury in patients on regular HD, and that the serum ferritin level is a surrogate marker for this pathological condition.

Genomic damage and circulating AGE levels in patients undergoing daily versus standard haemodialysis

BACKGROUND

Patients with end-stage renal failure, whether on conservative or haemodialysis therapy, have a high incidence of DNA damage. It is not known if improved control of the uraemic state by daily haemodialysis (DHD) reduces DNA lesions.

METHODS

DNA damage in peripheral blood lymphocytes (PBLs) was evaluated in a cross-sectional study of 13 patients on DHD (2-3 h, 6 times/week), 12 patients on standard haemodialysis (SHD) therapy (4-5 h, 3 times/week) and 12 healthy age-matched volunteer controls. The biomarker of DNA damage used was micronucleus frequency. The assessed plasma parameters of microinflammation and oxidative stress were C-reactive protein (CRP), interleukin-6 (IL-6), neopterin, advanced oxidation protein products (AOPP), and homocysteine. We also measured plasma concentrations of the circulating advanced glycation end products (AGEs) MGI (methylglyoxal-derived imidazolinone), CML (carboxymethyllysine), imidazolone A (3-deoxyglucosone-derived imidazolinone) and AGE-associated fluorescence.

RESULTS

Compared to SHD, DHD was associated with significantly lower DNA damage, approaching the normal range. Micronuclei (MN) frequency averaged 29.1 MN+/-5.9/1000 binucleated (BN) cells in the SHD group, which is significantly elevated (P<0.01), 14.8 MN+/-4.0/1000 BN cells in the DHD group, and 13.2 MN+/-3.04/1000 BN cells in the controls. CRP and AOPP were in the normal range (and similar between the dialysis groups). In contrast, IL-6 and neopterin were significantly elevated, with lower values associated with DHD as compared with SHD. The increased levels of AGEs tended to be lower in the DHD group, reaching significance for CML and imidazolone A.

CONCLUSIONS

Overall, it was found that genomic damage in PBLs is lower in patients on DHD than in those on SHD. Lower plasma concentrations of uraemic toxins, including circulating AGEs, may account for the differences. To confirm these data, prospective clinical trials need to be performed.

The effects of chronic kidney disease and renal replacement therapy on circulating dendritic cells

BACKGROUND

The mechanisms underlying the immunodeficiency of chronic kidney disease (CKD) are incompletely understood. Recently, we described decreased numbers of myeloid (m) and plasmacytoid (p) dendritic cells (DCs), considered the most important antigen-presenting cells, in peripheral blood of patients on chronic intermittent haemodialysis (CIHD). In this study, we analysed whether this reduction resulted from CKD or from renal replacement therapy (RRT).

METHODS

Using flowcytometry, we quantified mDCs and pDCs in peripheral blood of patients maintained on CIHD (n = 37), continuous ambulatory peritoneal dialysis (CAPD; n = 29), and patients with CKD not receiving RRT (n = 37). Twenty-nine healthy volunteers served as controls.

RESULTS

Patients with CKD (n = 103) had lower pDC and mDC counts compared with volunteers: 4.2 vs 8.3 and 10.0 vs 13.8 x 10(6) cells/l, respectively (P < or = 0.001). Within the CKD group, pDC counts did not differ between patients on CIHD, CAPD and those not receiving RRT (3.6 vs 5.0 vs 4.9 x 10(6) cells/l, respectively). In the latter group, pDC numbers correlated with the glomerular filtration rate (GFR; Spearman's r = 0.49; P<0.01). In contrast, mDC counts of patients on CIHD were lower compared with patients on CAPD (7.5 vs 10.1 x 10(6) cells/l; P = 0.039) and patients not receiving RRT (13.7 x 10(6) cells/l; P<0.001). Among non-dialyzing patients, no correlation existed between GFR and mDC numbers, which were comparable to those of volunteers, even when only non-dialyzing patients with a GFR below 15 ml/min were analysed.

CONCLUSIONS

Circulating DC counts are decreased in patients with CKD; for pDCs, this reduction is primarily related to the loss of GFR, whereas the dialysis treatment appears to affect mDC numbers.

Clinical course of haemodialysis patients with malignancies and dose-adjusted chemotherapy

BACKGROUND

Chemotherapy is not given routinely to patients with malignancies receiving chronic haemodialysis because evidence of a clear benefit is still lacking and severe side effects are feared. The aim of our retrospective study was to analyse the methods of dose adjustment and the clinical course of chronic haemodialysis patients with malignancies treated by chemotherapy.

METHODS

Between 1985 and 2001, a total of 48 cycles of 21 chemotherapy protocols were administered to 16 dialysis patients with nine haemoblastic and seven solid malignancies. We compared the dose actually administered with that theoretically derived from the proportional dose reduction rule of Dettli and the rule of Giusti and Hayton, using published pharmacokinetic parameters.

RESULTS

Kaplan-Meier estimates of median survival time were 30 months in patients with haemoblastic malignancies and 10 months for patients with solid malignancies. Eleven chemotherapies were administered in standard dosages and 10 chemotherapies in reduced dosages (39-80% of the regular dose); in all therapies, however, the dose was significantly higher than proposed by the Dettli rule (P<0.01).

CONCLUSION

Chemotherapy in patients with haemodialysis is feasible. Individual dose adjustment should be performed on the basis of pharmacokinetic data and the general condition of the patient, but it is still a matter of expert judgement, as there is no formal evidence available.

Genomic damage in end-stage renal failure: potential involvement of advanced glycation end products and carbonyl stress

In patients with chronic renal failure, genomic damage has been shown by numerous biomarkers, such as micronuclei frequency and comet assay (single-cell gel electrophoresis) in peripheral lymphocytes, 8-hydroxy 2'-deoxyguanosine (8-OH-dG) content in leukocytes, mitochondrial DNA deletions in skeletal muscle tissue and hair follicles, as well as in DNA repair mechanisms in freshly isolated lymphocytes after ultraviolet light exposure. In the pathogenesis of DNA damage--besides genetic influences, enhanced reactive oxygen species (ROS), and lipid peroxidation-the genotoxic potential of advanced glycation end products (AGEs) and reactive carbonyl compounds deserve special attention. In fact, reactions of glucose with DNA can lead to mutagenic DNA AGEs. In vitro, incubation of tubulus cells with various AGEs and methylglyoxal induces DNA damage, which is suppressed by antioxidants. This underlines the role played by oxidative stress in DNA damage.

Disturbances of purine nucleotide metabolism in uremia

The increased concentration of adenosine triphosphate (ATP) in erythrocytes from patients with chronic renal failure (CRF) has been observed in many studies but the mechanism leading to these abnormalities still is controversial. It is believed that hyperphosphatemia and metabolic acidosis triggering enhanced reutilization of purine bases are the factors responsible for changes in erythrocyte nucleotide concentration. During the past decade we have performed several studies. A summary of the obtained results is presented. A high-performance liquid chromatography technique was used for the determination of plasma and intraerythrocyte nucleotide concentrations. Labeled adenine and adenosine were used for measuring adenine incorporation. In CRF patients treated conservatively increased concentrations of ATP levels and other nucleotides such as adenosine diphosphate were found. Adenosine monophosphate and hypoxanthine levels were lower than in controls. In hemodialyzed patients both ATP and adenosine monophosphate intraerythrocyte concentrations were higher than in controls. At the same time, adenosine monophosphate and hypoxantine level were comparable with levels in healthy people. The main pattern of nucleotides during hemodialysis remained unchanged, independent from the mode of therapy. The only exception was a decreased level of hypoxantine. Results of a consecutive study have suggested that the increased rate of adenine incorporation into the adenine nucleotide pool could be partially responsible for the increased ATP concentration in uremic erythrocytes. Last but not least, trying to elucidate the pathomechanism of adenine nucleotide disturbances in uremia, we have found that the concentration of N-methyl-2-pyridone-5-carboxamide (2PY), one of the end products of nicotinamide-adenine dinucleotide degradation, were enhanced in CRF patients to values that are potentially toxic. Our findings suggest that 2PY could be a novel uremic toxin. Disturbances of nucleotide metabolism are one of the important components of uremic syndrome.