Abbott and Mayo Clinic validated a tampon-based endometrial cancer test that uses PCR detection of DNA methylation markers from self-collected vaginal fluid. The platform is designed as a less invasive alternative for a biomarker approach where standard sampling can be uncomfortable and less effective across diverse risk groups. For oncology monitoring, methylation-based circulating tumor DNA (ctDNA) analysis advanced as a practical strategy for tracking metastatic breast cancer response and progression during CDK4/6 inhibitor therapy. By reading methylation patterns in ctDNA, the approach aims to capture tumor dynamics during treatment. Both stories underscore momentum in minimally invasive biomarkers—from patient self-collection to serial liquid biopsies—to improve earlier detection and more responsive clinical decision-making.