The role of cell-free circulating DNA in the diagnosis and prognosis of prostate cancer.

The presence of small amounts of circulating DNA in plasma was demonstrated 60 years ago. Since then, cell-free DNA has been tested for quantity, fragmentation pattern, and tumor-specific sequences in patients with various malignancies. Recent studies have shown that cell-free DNA levels are distinctly increased in most patients with prostate cancer (PCA) and that the DNA fragmentation pattern is different from healthy individuals and patients with benign prostate disease.