We enrolled 45 patients with metastatic renal cell carcinoma (RCC) at a progressive disease between March 2003 and April 2008 to assess the impact of an anti-inflammatory treatment regime in combination with metronomic low-dose chemotherapy. 42% of the patients had been systemically pre-treated. Therapy consisted of etoricoxib 60 mg daily plus pioglitazone 60 mg daily, day 1+, low-dose interferon-α 4.5 MU sc three times a week, week 1+ and low-dose capecitabine 1 g/m(2) twice daily orally for 14 days, every 3 weeks, day 1+, until disease progression. Objective response was observed in 35% of the patients (PR 27, CR 9%), which was paralleled by strong CRP decline for all patients with initially elevated CRP levels (n = 32). CRP values decreased from mean 42.3 mg/L (range 9.1-236), to 11.1 mg/L, (range 1.1-35.6), P = 0.006. Median overall survival and progression-free survival for the total cohort were 26.9 and 7.2 months for patients with elevated CRP 24.4 and 11.3 months (95% CI, 22.8-31.0/5.7-16.9) and 13.8-2.6 months (95% CI, 6.5-21.1/0.4-4.8) for the non-elevated CRP group, respectively (P = 0.082/0.017). Median observation time: 26.1 months; Overall survival at 5 years: 18%. Toxicity>WHO grade 3 was reported: Hand-foot syndrome in 16 patients (36%), diarrhea in 4, and pneumonia in 2 patients. Our data allow us to conclude that the control of tumor-associated inflammation is an important therapeutic principle in patients with metastatic RCC.