Circulating Tumor DNA

Circulating tumor DNA (ctDNA) is genetic material released by cancer cells that can sometimes be detected in a blood sample. Explore patient-friendly articles, expert perspectives, and personal stories about how ctDNA testing may help inform cancer care—from assessing the possibility of cancer remaining after treatment to monitoring for signs of recurrence. Learn what a positive or negative result may mean, why results must be considered alongside scans and other tests, and what questions to ask your care team about whether testing is right for you.