Combined circulating tumor DNA and protein biomarker-based liquid biopsy for the earlier detection o

Pancreatic cancer remains one of the deadliest solid malignancies and over the past few decades, not much progress has been made with regards to its diagnosis and therapy. Because most early-stage pancreatic cancers are 'stumbled upon' during imaging scans and are far advanced in otherwise symptom-free patients, there is an urgent need for early-stage diagnostic markers. Liquid biopsies are relatively non-invasive tests that hold great promise as diagnostic tools in pancreatic cancer, especially with a combination of circulating tumor (ct) quantifier and genetic analysis.

The Johns Hopkins scientists showed how a combination of mutations in ctDNA and protein markers can remarkably improve sensitivity (while retaining specificity) of a potential screening test. They found that this combinatorial approach performed better than any single marker. The test detected almost two-thirds of pancreatic cancers that had no evidence of distant metastasis at the time of surgical resection (64% sensitivity) with 99.5% specificity.

This study sets the pace for future evaluation of individuals at high-risk for pancreatic cancer (e.g. those with familial history of pancreatic cancer or new-onset diabetes patients) and offers cautious optimism for the use of such combinatorial approach in other cancers.

Original article: JD. Cohen et al., "Combined circulating tumor DNA and protein biomarker-based liquid biopsy for the earlier detection of pancreatic cancers" PNAS (2017). www.pnas.org/cgi/doi/10.1073/pnas.1704961114