Several phase II trials have shown that gemcitabine and fluoropyrimidines have marginal but definite activity in patients with metastatic renal cell cancer (mRCC). We retrospectively analyzed the 193 mRCC patients consecutively seen in our institutions during the last 11 years, of whom 39 were treated with chemotherapy (CT): 16 were treated with CT alone (gemcitabine and 5-fluorouracil) and 23 with the same regimen plus low dose of interleukin-2 and interferon-alpha. The main end point of the analysis was to estimate response rate and time to progression (TTP); the secondary end point was to evaluate overall survival (OS) and toxicity. Overall TTP was 3.2 months (95% confidence interval: 2.22-4.18). Three patients (7.7%) achieved a partial response and 10 (25.6%) stable disease. Median OS was 9.23 months (95% confidence interval: 7.16-11.31) and the 1-year survival rate was 40.6%. Although not statistically significant, the response and disease control rates were better in the pretreated patients (8% vs. 7% and 44% vs. 14%), with a favorable trend for TTP and OS (4.9 vs. 3.2 mo and 12.9 vs. 4.2 mo). Grade 3 to 4 toxicities included hematologic toxicity and depressed mood. OS was strongly influenced by performance status, the presence of brain metastasis, and response after 3 cycles of therapy. In these mRCC patients, both CT and chemoimmunotherapy showed modest but definite activity and a regimen CT-based should be offered to patients with progressive mRCC. The association of these treatments with antiangiogenetic agents should be tested in future trials.

Very low doses of recombinant interleukin-2 (rIL-2) and interferon-alpha (rIFN-alpha) induce, in patients with advanced renal cell carcinoma (RCC) clinical response rate and median survival time comparable to other protocols, other than immunological response in terms of expansion of NK cells and cT lymphocytes. The aim of this pilot study was to verify whether very low dose immunotherapy can enhance NK cell cytotoxicity against tumoral target cells. Eight patients with advanced and 13 patients with localised disease received 4-week cycles of rIL-2 (total dose per week 7 MIU/m(2), s.c.) and rIFN-alpha (total dose per week 3.6 MUI/m(2), i.m.) according to the scheme proposed by Buzio et al. Neutrophils, monocytes, eosinophils, NK cells (CD56+bright, CD56+dimmer, CD3-CD56 +), NK-T cells (CD3+CD56+), Th-lymphocytes, cT-lymphocytes, HLA-DR+ and CD25+ lymphocytes and NK cell cytotoxicity were evaluated before and after cycle. The treatment led to the significant expansion of eosinophils (P < 0.001), NK cells (P < 0.001), CD56+bright (P < 0.001), CD56+dimmer (P < 0.001), Th-lymphocytes (P = 0.001), cT-lymphocytes (P = 0.014), HLA-DR+ (P = 0.007) and CD25+(P = 0.002) cells. Neutrophils significantly decreased (P = 0.001), whereas no significant effect was observed on monocytes (P = 0.22) or NK-T cells (P = 0.20). Patients with localised disease responded significantly better to treatment than metastatic patients in terms of the expansion of CD56+bright (P = 0.038), DR+ (P = 0.021), CD25+ (P = 0.006) and Th-lymphocytes (P = 0.014). The NK cell cytotoxicity was significantly increased by the immunotherapy in the whole population (P = 0.021) and similarly in the two groups of patients (P = 0.860); a reverse relation, even if not significant, was seen between the variation of NK-T cells and NK cells cytotoxicity (r = -0.39; P = 0.074).