Urine and serum free IGF-1 levels in patients with bladder cancer: a brief report

Insulin-like growth factor (IGF)-1, a mitogenic and anti-apoptotic peptide, can affect the proliferation of epithelial cells, and is thought to play a role in cancer development. The free IGF-1 represents the biologically active fraction of IGF-1. We hypothesised that there is a difference in free IGF-1 levels in the urine and serum from patients with TCC and normal subjects. Urine and blood samples were collected from 30 cases of superficial TCC and an equal number control subjects without malignancy. Free IGF-1 levels were measured in duplicate by radioimmunoassay. Specimens of bladder carcinoma were staged histopathologically using the Mostoffi grading system. Statistical analyses were performed using the Mann-Whitney U-test, Pearson correlation and covariate analysis. There was no significant difference in urine and serum free IGF-1 levels between the two groups. The correlation between urine and serum free IGF-1 levels and age was not significant. There was also no significant relationship between free IGF-1 levels and histopathological grading. The results of this pilot study reveal that the free IGF-1 level does not help predict tumour marker in the patients with bladder cancer.