Cell-free Serum DNA in Patients with Bladder Cancer: Results of a Prospective Multicenter Study

Cell-free DNA may serve as a biomarker for patients with cancer; we designed our study to determine its potential in patients with bladder cancer (BCA). Short β-actin (ACTB)-106 and large ACTB-384 fragments were quantified using real time PCR (RT-PCR); the ratio of ACTB-384/ACTB-106 was defined as DNA integrity. We analyzed the serum from 95 patients with and from 132 without BCA. Patients with BCA had increased ACTB-106 levels and lower DNA integrity compared to patients without cancer. However, patients undergoing transurethral bladder resection (TURB) with histological exclusion of BCA had a similar ACTB-106 level and DNA integrity, as patients with BCA. Cell-free DNA was not correlated with smoker status, pT stage, grade or lymph node metastasis, or DNA integrity. There was a weak inverse correlation of age with DNA integrity in patients with BCA. Analysis of serum cell-free DNA levels and fragmentation patterns are of limited value regarding the identification of patients with BCA.