The elevated circulating concentrations of interleukin-6 and interleukin-10 following resection of renal cancer may reflect a continuing Th2 cytokine response as increased intra-tumoural CD4+ T-lymphocyte infiltrate has been shown to be associated with poor outcome, independent of grade, in patients with renal clear-cell cancer (Bromwich et al, 2003). Here, CD4 is linked to clear cell renal carcinoma.