What You Need to Know:
“Liquid Biopsy”, also known as a cell-free DNA (cfDNA) test, is a newer concept in the diagnosis of certain types of cancers. The saliva, blood or urine is collected and examined to determine if genomic cancer biomarkers are present. Cancers are often diagnosed by uncomfortable, invasive, and expensive tissue biopsies following an abnormal imaging study, but this may soon change as results of the Noninvasive versus Invasive Lung Evaluation (NILE) prospective study become available.
The NILE prospective study included 282 patients with newly diagnosed, advanced and untreated non-small cell lung cancer (NSCLC). The aim of this study was to determine if Guardant360, a cfDNA test, could detect at least one out of nine associated NSCLC genomic biomarkers when compared with a traditional tissue-based biopsy. The results were favorable showing Guardant360 detected at least one guideline-recommended biomarker mutation in more cases than tissue-based tests alone, and it delivered results much faster in an average of nine days versus 15 days with tissue biopsy.
Speed and reliability weren’t the only benefits of this cfDNA test. Guardant360 was able to more accurately identify treatment choices for patients diagnosed with NSCLC. This should have a positive impact on treatment plans as response rates to adequately identified targeted therapy are higher than response rates to first-line chemotherapy or immune checkpoint inhibitors. Overall, liquid biopsies are less expensive, noninvasive, may detect cancer early, and can aid in monitoring treatment response, which may ultimately increase survival rates.
The downside of screening with a liquid biopsy is that it may result in an increase in false positive results which can lead to overdiagnosis and overtreatment. More research is needed to determine if cfDNA tests could be implemented as a screening tool to detect other types of cancer, such as breast and colorectal.
Read About "Liquid Biopsy" to Detect Cancer:
Goodman and Gilman’s: The Pharmacological Basis of Therapeutics, 13e: Chapter 65. General Principles in the Pharmacotherapy of Cancer
Harrison’s Principles of Internal Medicine, 20e: Chapter 66: Prevention and Early Detection of Cancer