DeciBio Liquid Biopsy Weekly Digest
July 28th, 2020
The largest buzz in headlines this week was generated by Singlera when they released positive preliminary data from the Taizhou Longitudinal (TZL) Study for PanSeer. PanSeer uses ctDNA methylation markers to detect stomach, esophageal, colorectal, lung or liver cancers and will compete with the likes of Thrive Earlier Detection (~10 cancers) and GRAIL (>50 cancers) as a blood-based pan-cancer screening assay. The TZL study collected samples from 123,115 healthy patients over time while they were monitored for cancer occurrence. The preliminary analysis consisted of a group of 605 asymptomatic patients, 191 of whom developed one of the 5 cancers measured by PanSeer. It was found that PanSeer detected cancer in 88% of these patients post-diagnosis at 96% specificity. PanSeer was able to identify 95% of asymptomatic individuals who were later diagnosed with cancer within 4 years of their blood draw. Further validation is needed, but the prospects of identifying cancer 4 years prior to conventional diagnosis is certainly exciting.
ctDNA methylation has established itself as a crucial analyte for the early detection of cancer and may prove to be useful later in cancer care. Genome Profiling and Fox Chase Cancer Center are collaborating to develop a potential predictive marker for checkpoint inhibitors in lung cancer patients. Immuno-oncology is known to only have drastic results in a limited group of patients. Markers like PD-L1 status and Tumor Mutation Burden are still being understood and are primarily determined by a tissue sample. The goal of this collaboration is to determine if methylation sites on circulating immune cells can predict a lung cancer patient's response to CPIs. If successful, this test could save a patient from undergoing a risky biopsy as well as better inform treatment decisions.
