Immunomodulatory influence of embolization of renal artery in patients with renal cancer
Article published in Urologia Polska 2008/61/Supl. 1.

authors

Tomasz Syryło, Wanda Stankiewicz, Henryk Zieliński, Marek P. Dąbrowski

Klinika Urologii WIM w Warszawie
Wojskowy Instytut Higieny i Epidemiologii w Warszawie

summary

Introduction.

Renal tumors consists 2-4% of all neoplasms in adults. The most frequent malignant renal tumor is renal cell carcinoma (RCC). In 25-30% of patients distant metastases are present at the time of the first diagnosis. RCC is chemo- and radiotherapy resistant and belongs to the most immunogenic neoplasms in man. The embolization of the renal artery (ERA) results in a strong stimulation of immune system and represents valid element of therapeutic strategy in patients suffering from RCC. ERA can be performed as a preliminary operation before the nephrectomy or as a palliative procedure in the case of the large, inoperative renal tumors. The implementations of the modern investigative methods make it possible to better understand the influence of ERA on the functions of immune system.

Objectives.

Determination of the expected immunomodulatory influence of the embolization of renal artery in patients suffering from renal cancer.

Materials and methods.

In the group of 38 patients with RCC (diagnosis confirmed by CT or MNR) embolization of renal artery has been performed. In 12 of them in time of 2-6 weeks after ERA the nephrectomy was performed (group N), the remaining 26 patients were left without nephrectomy (group E). In all patients the samples of mononuclear cells were isolated from the blood and tested immunologically. The tests comprised quantitative determination of cellular phenotypes (CD4, CD8, CD4/CD8) in flow cytometry and in the system of microcultures estimations of T-cell functions (response to PHA and to Con A, saturation of IL-2 receptors, T-lymphocyte suppressive activity – SAT index) and monocyte immunogenic activity (LM index). The immunological tests were done three times: in the group E before ERA, 2-6 weeks and 12 weeks

after ERA, in the group N before ERA, 2-6 weeks and 12 weeks after surgery.

Results.

In the group N T lymphocyte response to PHA, initially lower than normal, increased significantly 12 weeks after nephrectomy (p<0.01), similarly, in the group E response to PHA after transitional decrease increased also at 12 weeks after ERA. In the group N T cell response to Con A increased after ERA but, in contrast to that, the response decreased to the value of 27.2 x 103 dpm in the group E after ERA. The saturation of IL-2 receptors, initially lower than normal in the both groups, reached the normal values (>90%) 12 weeks after the surgery. The T cell suppressive activity (index SAT), which represents immunoregulatory ability of T lymphocytes, initially lower than normal, improved to the normal values (>30%) in both groups after surgical procedures. The immunogenic activity of monocytes (index LM) increased considerably in the

group N directly after ERA and decreased thereafter. In the group E the value of LM index, initially and 6 weeks after ERA higher than normal, decreased to the normal value (6.03) 12 weeks after ERA. Determinations of the T cell phenotypes showed decreased values of TCD4 and increased values of TCD8 cells in both groups of patients. After performed surgical procedures the ratio of TCD4/TCD8 improved in both groups.

Conclusions.

The immunological examinations indicated that the patients with renal cancer demonstrate both quantitative (ratio of TCD4/TCD8) and functional immunoregulatory deficits of T lymphocytes (lower than normal values of SAT, IL-2 receptor saturation and, partially, lower response to mitogens). Embolization of the renal artery (ERA) introduces strong immunostimulatory element in these patients, increasing immunogenic activity of monocytes and improving the parameters characterizing the immunological competence of T lymphocytes. The observed immunotropic effects of ERA in patients with renal cancer can be estimated as a valuable therapeutic element, beneficial for the further course of the disease.