To examine the relationship between the systemic inflammatory response (C-reactive protein, CRP), tumour interleukin-6 receptor and cyclooxygenase (COX)-2 expression, tumour T-lymphocytic (CD4+, CD8+) infiltration and cancer survival in patients undergoing resection for renal cell carcinoma (RCC), as both the local and systemic inflammatory responses appear to predict the outcome in these patients.
PATIENTS AND METHODS
The study included 60 patients undergoing nephrectomy for localized RCC. Pre-operative circulating CRP levels were measured and tumour interleukin-6 receptor and COX-2 expression, tumour CD4+ and CD8+ T lymphocytes were assessed using immunohistochemical analysis.
The median follow-up was 78 months, with 14 patients relapsing from their disease and nine cancer-specific deaths. On univariate and multivariate survival analysis, tumour stage and grade and CRP levels were identified as significant factors associated with relapse-free and cancer-specific survival. There was a significant direct relationship between Fuhrman grade and CD4+ T-lymphocytic infiltrate (P < 0.05). An increase in tumour expression of interleukin-6 receptor was weakly associated with an increase in tumour CD8+ T-lymphocytic infiltration (P = 0.057). An increase in tumour CD4+ T-lymphocytic infiltration was associated with an increase in CD8+ T-lymphocytic infiltration (P < 0.01).
The present results suggest that tumour-based factors such as interleukin-6 receptor and COX-2 expression or T-lymphocytic subset infiltration are subordinate to systemic factors such as CRP level in determining survival in patients with localized RCC.