What biological factors could cause a true false positive on all three markers?

A true false positive would require a healthy person to have all three cancer biomarkers elevated above 1.5× HL simultaneously without cancer being present. In published Yenos studies, zero healthy samples exceeded the 1.5× HL threshold on initial testing — suggesting this is extremely rare. Theoretical causes of false positives include: severe systemic inflammation (e.g., sepsis, acute pancreatitis) causing a temporary surge in circulating miRNA; pregnancy (which dramatically elevates miR-21 and other miRNAs through placental secretion); or recent heavy physical trauma causing massive cell death and miRNA release. The two-test confirmatory protocol reduces false positives further by requiring the elevation to be reproducible on a second independent measurement of the same sample.