Postoperative long-term course of peripheral blood immune parameters and immunomodulating effects of keyhole limpet hemocyanin in patients with nonmetastatic renal cell carcinoma.

Abstract

Therapeutic approaches to metastatic renal cell carcinoma (RCC) often focus on the application of immune modulators; the success rates, however, are not satisfactory. Up to the time of this study, no diagnostic tool has been available to select those patients who might profit from immunotherapy. Starting from this point, we have been assessing the immune status of patients suffering from RCC, intending to find markers that would characterize the more favorable prognosis. Our interest is focused not only on the metastatic but also on the nonmetastatic disease, i.e., the disease with the better prognosis. In the present study, we have assessed both the postoperative long-term course of several immune parameters of the peripheral blood and the reactivity of the immune system to immunostimulation with keyhole limpet hemocyanin (KLH) in patients with nonmetastatic RCC. In a prospectively randomized study, the verum group (n = 8) got 1 mg KLH per month up to 1 year while the control group (n = 9) got no immunostimulator after tumor nephrectomy. Both patient groups had stable or even increasing cell counts of lymphocyte subpopulations (T, B, natural killer, T4, T8 cells), and the humoral immunoactivation markers neopterin, beta 2-microglobulin and tumor necrosis factor increased considerably after tumor nephrectomy. An effect of KLH is evident 4-8 months postoperatively: here, the neopterin values in the KLH group are more than twice as high as in the control group. Thus, while patients with metastatic disease had turned out to be immunosuppressed (previous study), in patients with nonmetastatic RCC, both the long-term course indicating postoperative immunostimulation and the reactivity to KLH give evidence of immunocompetence.