“we are a long way from using liquid biopsies for detecting cancers”

Medscape – by Kate Johnson – While the idea of using a drop of blood to detect an occult cancer is still elusive, use of so-called liquid biopsies for cancer screening is at least a little closer to reality with the development of a new high-intensity genomic sequencing approach outlined here at the American Society of Clinical Oncology (ASCO) 2017 Annual Meeting.

A new test (under development by Grail Inc) highlighted in the ASCO press program uses high-intensity sequencing on circulating tumor DNA (ctDNA). It offers “an unprecedented combination of breadth and depth,” surveying 508 genes and yielding about 100 times more data than other currently used approaches, said investigator Pedram Razavi, MD, PhD, from Memorial Sloan Kettering Cancer Center in New York City.

Dr Razavi presented results from a concordance study in 124 patients with metastatic cancer, which showed that the new test picked up 89% of genetic changes that had been identified with regular tumor biopsy and 76% of “actionable” mutations that could be treated with targeted therapy.

“Our findings show that high-intensity circulating tumor DNA sequencing is possible and may provide invaluable information for clinical decision-making, potentially without any need for tumor tissue samples,” Dr Razavi commented.

“The ultimate goal would be detection of cancer in early, treatable stages,” he said during a press conference here.

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