In a “proof of concept” study, researchers have found evidence that transurethral resection of bladder tumor (TURBT) can cause “seeding of cancer cells into the bloodstream, according to a new report.
Researchers studied 16 patients newly diagnosed with suspected invasive bladder cancer. Prior to TURBT, a vascular surgeon placed a venous catheter into the inferior vena cava via the femoral vein. Blood samples were drawn before and during TURBT from both the IVC and a peripheral vein and analyzed for circulating cancer cells (CTCs). In 6 of 7 positive IVC samples (86%), the number of CTCs increased intraoperatively. Results were similar but less conclusive for corresponding peripheral vein samples.
“Although our findings show that unintentional infusion of cancer cells can occur during TURBT, the clinical consequences of such seeding are currently a matter of speculation,” the authors wrote in a report published in The Journal of Urology (2015;193:53-57).
The researchers concluded that, for now, it is unknown whether the release of tumor cells into the bloodstream will increase the risk for metastatic disease.
The researchers, led by Sigurdur Gudjonsson, MD, PhD, of Skåane University Hospital in Malmö, Sweden, explained that during TURBT, the bladder is infused with fluid, which can increase the pressure in the bladder to levels above that of the venous pressure. This poses a risk of cancer cells being infused into the venous system. Theoretically, they noted, this could induce micrometastasis that subsequently gives rise to distant site metastasis following cystectomy.