Introduction:
Transplant recipients have a significantly greater incidence of cancer, compared with the general population, who are referred to immunosuppressive therapy as an additional malignancy risk factor. Therefore, there is a need to search for an easy in clinical practice neoplasm predictor, especially for this group of patients.

Material and Methods:
A group of 74 (43M and 31F; aged 46.8 ± 12 years) kidney transplant recipients was investigated in a three-year follow-up study. During the time of observation, 7 patients were diagnosed with neoplasm (7.4 ± 1.5 years after transplantation). A serum level of IL2 (ELISA test) and mRNA level of IL1beta, IL10 and TNFalfa in peripheral mononuclear blood cells – PBMCs (QRT – PCR method) were measured in every year of observation. Analysis of variances and t-Student test were used in groups mean comparison: N – patients developing malignant neoplasm group (24 probes); M – set of probes from patients with malignancies at the moment of diagnosis (11 probes); P – set of probes from patients before developing malignant neoplasm (10 probes); C – control group of healthy transplant recipients (31 probes).

Results:
Among the analyzed agents, only serum IL2 level differed between the analyzed groups, with higher values in the M compared with the P group (p<0.05) and with C group (p<0.01). There were no differences neither between N and C or P and C groups (p = 0.98), nor any correlation between IL2 and IL1b, IL2 and TNFalfa.

Conclusions:
The results may indicate that IL2 serum level might be consider as a useful late unspecific cancer marker, although larger studies should yield verification of this finding.