What is a liquid biopsy?

A liquid biopsy is a blood test that looks for cancer cells, or pieces of tumor DNA, that a tumor has shed into the blood.

Because some tumor markers—including genomic markers such as tumor gene mutations—can be found in tumor fragments in the blood, a liquid biopsy is one way to measure the molecular characteristics of a cancer without taking a tissue sample. Some of these results may appear in reports linked to a pathology report.

A liquid biopsy is one tool among several, and results are used together with other tests. Your healthcare team is the best source of information about whether a liquid biopsy is useful in your situation.