Natera now offers two versions of their Signatera ctDNA blood test, and both work the same basic way: they analyze a patient’s tumor tissue once to build a personalized “fingerprint” of that cancer, then use blood draws over time to check whether tumor DNA is still circulating in the body. The difference is how much of the tumor’s DNA they read to create that fingerprint. The original Signatera (Exome) reads only the protein-coding portions of the tumor’s DNA, about 1–2% of the total genetic information. The newer Signatera Genome reads the entire tumor DNA blueprint, giving it a much larger pool of mutations to track. The practical result is that the Genome version can detect cancer at lower levels in the blood and may catch recurrence earlier, which could matter significantly for FLC patients, where tumors tend to have fewer mutations to begin with, making them harder to detect.
For FLC patients specifically, given the relatively low mutation burden typical of the disease — the genome-based version’s enhanced sensitivity could be a meaningful advantage
Dr. Kent and the Natera team met at ASCO and a more detailed interview will be coming out shortly as well as an updated paper on Signatera effectiveness in FLC patients.
Dr. Paul Kent (left), Dr. Ragini Adams (middle) Associate Medical Director, Oncology at Natera, Dr. Enrico de Toni (right) International Medical Director, Oncology at Natera