In a clinical study of 256 consecutive RCC patients investigating the relation between serum IGF-I and disease progression and survival (Rasmuson et al, 2004), researchers found that male and female patients with serum IGF levels greater than the median value were 38% less likely to die of RCC compared with patients with serum levels below the median (hazard ratio=0.62, 95% CI=0.41–0.95) and that IGF-I levels were inversely proportional to tumour stage and grade. Here, IGF1 is linked to neoplasm.