Incidence of cancer in kidney transplantation waiting list patients: a single center experience

INTRODUCTION

It is widely accepted that the risk of malignancies is significantly increased among patients with end-stage kidney disease (ESKD) and after kidney transplantation compared with the general population. Only a few data are available on kidney transplantation waiting list patients. The aim of this study was to investigate solid organ cancer incidence among subjects on the waiting list at a single center.

MATERIALS AND METHODS

We retrospectively reviewed the records of all patients enrolled on our kidney transplantation waiting list between August 1, 2008 and July 31, 2010, seeking to evaluate the causes of withdrawal from the list, incidence of cancer, type of neoplasm, and its correlation with clinical features. We estimated the ratio of observed to expected numbers of cancers, the standardized incidence ratio (SIR).

RESULTS

Among 1184 patients, we excluded 569 patients from the waiting list including 26 (4.56%) who displayed malignancies. The overall incidence of cancer was 0.11 events/person-months and the overall prevalence of cancer was 2.2%. In 97% of patients, the malignant disease was confined to the primitive organ of origin without secondary dissemination. We observed a prevalence of cancers related to ESKD (17; 65.38%). The SIR for all cancer types in our population compared with the general population was 2.22. The SIR for native kidney and thyroid cancers among our population compared with the general population was >10.

CONCLUSION

The incidence of cancer was significantly increased among kidney transplantation waiting list patients compared with the general population. Our study highlighted the importance of a careful, targeted neoplastic screening. It could be particularly important for ESKD-related malignancies like native kidney tumors or thyroid cancers.

The cardiovascular burden of end-stage renal disease patients

Patients with end-stage renal disease are 10 to 20 times more at risk of cardiovascular death than the general population. Traditional cardiovascular risk factors are not able to explain the increase in the onset of cardiovascular diseases in dialysis patients. Some of the most important non traditional risk factors in uremic patients are: the inflammatory state of the patients, cytokines and growth factors, hyperhomocysteinemia, the presence of alterations of the calcium phosphorous product which can already be in progress when the glomerular filtration rate decreases to less than 60 mL/min. Clinically, these alterations cause vascular calcifications, calcifications of the heart valves and calcific uremic arteriolopathy or calciphylaxis. The pathogenesis of vascular calcification is complex and cannot be assigned to a simple, passive process: in fact, it includes factors which promote or inhibit calcification. In turn, these pathologic conditions have been found to be highly predictive of general and cardiovascular death. Given the serious clinical consequences that vascular calcifications can cause, it is necessary to carry out an early mapping of the traditional and non traditional risk factors of uremic patients as it seems that therapeutic interventions aimed at reducing or inverting the calcification process can improve the outcome of patients, above all when they are started quickly.

[Chronic allograft dysfunction: role of immunosuppressive treatment]

Renal transplantation is the treatment of choice for patients with end-stage renal disease. In recent years a major improvement has been observed in short-term graft survival, but there has been no corresponding improvement in long-term survival. Chronic allograft dysfunction (CAD) is an anatomical and clinical alteration that can lead to the loss of the transplanted organ without any specific cause. The pathogenesis of CAD, which still remains to be fully clarified, involves both immunological factors (acute rejection, subclincial rejection, HLA mismatches between donor and recipient, noncompliance, etc) and non-immunological factors (marginal donor ischemia/reperfusion injury, infection, cardiovascular risk factors, nephrotoxicity, etc). Immunosuppressive therapy represents one of the strategies for the prevention of CAD. The introduction into clinical practice of novel immunosuppressive agents with no or lower nephrotoxicity, like mycophenolate mofetile, rapamycin and everolimus, will make therapeutic strategies aimed at decreasing the incidence of CAD feasible.