Malignant neoplasms are among the most frequent causes of morbidity and mortality in general population. Not so long ago the evident neoplastic disease excluded inclusion into chronic RRT program. The situation was changed during the last years and now only the advanced, disseminated neoplastic disease may serve as a reason for refusing this therapy (1). In patients presenting with renal failure, as well as in the dialyzed ones, the neoplasms frequency is higher than in general population and is rising throughout the last decades (1-3). This is caused by the malfunction of the immunological system due to uremic state and to the prolonged exposure to uremic toxins. Simultaneously, the aging population and the progress in treatment of other diseases (cardiosurgery, vascular surgery, effective treatment of metabolic and vascular diseases) allow for registering new patients with neoplastic diseases into the group of persons beginning the RRT – these patients simply live long enough, to develop, and present with neoplastic disease at the beginning of RRT. A different problem would be the group of patient for whom the relation between appearance of the neoplasm and the necessity to initiate RRT is strictly related to a specific effect of neoplasm, e.g. infiltration of the urinary tract by a tumor – like in the obstructive nephropathy, or like in myeloma nephropathy. In this group a deterioration of kidney function (acute or chronic) may cause a necessity of initiating the RRT also independently. Many medical reports confirm the huge frequency of malignant neoplasms in the population of haemodialysed patients (2-6), and the increasing incidence of neoplastic diseases in patients with chronic renal failure and during RRT (2, 3, 5). In some of these patients the developing neoplasm may induce the uremic state demanding RRT. That would be in cases of obstructive nephropathy caused mainly by infiltration of the urinary tract by cancers of prostate, uterus, bladder or kidney. Also, many patients with haematological diseases develop severe uremic condition demanding RRT, which is on the one hand strictly bound to the specificity of haematological disorder (e.g. myeloma nephropathy or glomerulopathies in lymphatic system diseases) (7-9), and on the other hand with the specificity of the therapy (nephrotoxic effect of chemotherapy, higher incidence of AKI because of prerenal causes) (7-9).

The goal of the study was to analyze the incidence of malignant neoplasms in the group of patients beginning renal replacement therapy (RRT).

This is a retrospective observational study based on the analysis of patients’ medical records. All patients commencing RRT in the years 2001-2015 (till June) at the Dialysis Unit DIAVERUM in Warsaw, Ceglowska Street 80 (previously Non-Public Health Care Centre “Dialysis and Diagnostics Centre”), at the Priest J. Popiełuszko Bielański Hospital in Warsaw, were analyzed. In every patient with neoplastic disease in anamnesis or diagnosed at the moment of qualification to RRT, the decision on initiating the RRT was done individually, based on clinical and biochemical indications, and taking into account the good general condition (despite neoplastic disease), the forecasted surviving time, and with an intention of delivering the optimal therapy, especially to minimize side effects and patient’s suffering, and avoiding the futile therapy.

In years 20012-2015 (till June, 30) 653 adult patients initiated the chronic RRT. The dialysis was also performed in 16 patients presenting with acute kidney injury related to the neoplastic disease. Out of these 669 patients (270 females and 399 men) 72 (12.5%) were diagnosed with neoplastic disease time and/or cause-related with the beginning of RRT, and 12 had the diagnosis made beforehand – 8 (75%) initiated RRT with the relapse of neoplastic disease, (including 1 in the dissemination phase of disease), 4 (25%) had a new neoplasm. Two neoplasms in one patient were diagnosed in 8 patients: 4 patients with existing cancer were diagnosed with another one (patients with bladder cancer had new diagnosis of kidney cancer), and 4 developed new cancer with no relapse of the one diagnosed in the past.