Lack of evidence for increased level of circulating urothelial cells in the peripheral blood after transurethral resection of bladder tumors

PURPOSE: Aggressive intervention against the bladder wall during transurethral resection of bladder tumors (TURBT) causes damage and leakage from blood vessels to the bladder lumen. The aim of this study was to determine whether TURBT could increase the level of circulating urothelial cells. METHODS: Expression of tumor markers, discriminative for nucleated blood cells and urothelium, was evaluated by quantitative (q) RT-PCR on RNA isolated from peripheral blood samples of 51 patients who underwent TURBT for ≥cT1c bladder tumors. RESULTS: Four of 14 studied genes, epidermal growth factor receptor (EGFR), Collagen α-1(I) chain, Mast/stem cell growth factor receptor (KIT) and CD47, exhibited significant differences in gene expression between controls and cancer patients. While TURBT did not significantly increase the number of PCR-positive results of any transcripts, positive RT-PCR detection for EGFR was significantly less frequent on day 30 compared to results obtained before surgery. CONCLUSIONS: Although the results of our study do not provide evidence for increased tumor cell release into the peripheral blood after TURBT, they seem to indicate that EGFR mRNA measurement in the blood may provide useful information for urologists. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s11255-011-0102-z) contains supplementary material, which is available to authorized users.