Pretreatment serum markers and lymphocyte response to interleukin-2 therapy

Lymphocytosis is a marker of subcutaneous interleukin (IL)-2 therapy effica cy, whereas baseline elevated inflammatory indices were noticed in IL-2-res istant disease. The aim of this study was to analyse the relationship betwe en pretreatment circulating values of IL-6, neopterin, sIL-2R, ESR and the changes in lymphocyte number in response to IL-2 administration. Twenty met astatic renal cell cancer patients were treated with subcutaneous IL-2 immu notherapy (6 000 000 IU day(-1) for 6 days per week for 4 weeks); tumour re sponse consisted of partial response (PR) in four patients, stable disease (SD) in eight patients and progressive disease (PD) in eight patients. Abno rmally high pretreatment values of each marker were found as follows. IL-6 in seven patients, neopterin in nine patients, sIL-2R in 13 patients, In re sponse to IL-2 immunotherapy, a significantly higher mean increase in lymph ocyte number and a higher percentage of patients with tumour response or st able disease were observed when pretreatment values of IL-6, neopterin and sIL-2R were within the normal range, in comparison to patients with high va lues for these markers. The pretreatment excess of these serum inflammatory markers seems to negatively influence both the host and tumour response to IL-2 administration, by preventing the IL-2-induced lymphocytosis and resu lting in tumour progression, Further studies are requested to verify ii ove rall survival and quality of life may depend on pretreatment host immune st atus and/or lymphocyte response after IL-2 administration.