[Kidney transplantation and tumors].

Background: In conjunction with organ transplantation and subsequent treatment there is a number of influences which potentiate the development and possibly the growth of tumours. This applies naturally also to transplantations of the kidneys. The objective of the present study was to assess the frequency and type of tumours in patients after renal transplantation and compare these results with data of the at present most extensive worldwide register in Cincinnati (CTTR).
Methods and Results: The authors analyzed a group of 879 patients where within the period between March 21, 1966 and Sept. 29, 1992 a total of 989 renal transplantations were performed from dead relations-934 or from living relations (55); in 38 patients combined transplantations of kidney and pancreas were performed. The group comprised 59% men and 41% women. In the course of years the pattern of prophylactic immunosuppression changed: up to 1984 the basic drug was azathioprin combined with prednisone, during the same year cyclosporin A was introduced as a rule in a triple combination with azathioprin and prednisone; less frequent was the combination of cyclosporin A and prednisone. For antirejection treatment corticoids were used, later supplemented with polyclonal or monoclonal antibodies. During the period 1966-1992 tumourous diseases were diagnosed in 32 patients (3.64%); in two of these patients; combined transplantation of the kidney and pancreas was performed (5.3%). There was no difference in the frequency of tumours in patients with immunosuppressive medication (azathioprin with prednisone-3.80%) and cyclosporin A (3.51%). The mean age of the patients at the time of diagnosis of the tumour was 50.2 years, the interval after transplantation was 42.2 months (in patients treated with azathioprin 57 months, in the group treated with cyclosporin A 29.2 months). As far as the location of tumours is concerned, tumours of the skin predominated 25% (as compared with CTTR where it was 30%), tumours of the patient's own kidneys 21.9% and of the urinary pathways 15.6%, tumours of the gastrointestinal tract 12.5%, lymphomas in 9% (as compared with 15-20% in CTTR), tumours of the lungs 6.25% and other localizations also 6.25%. Some tumours frequently encountered in the population (lung cancer, cancer of the prostate, breast, colorectal carcinoma) are less frequent in patients after transplantation (CTTR); however, this fact was not confirmed by the authors. In renal tumours and tumours of the efferent urinary pathways data on analgetic nephropathy were encountered very frequently.
Conclusions: The prevalence of tumours of various organs in patients after transplantations of the kidneys are not a frequent but a very serious complication. Its causes are multifactorial. The group after renal transplantations in the Czech Repubic has some deviations as compared with CTTR as regards affection of organs.