Guardant Health is collecting real-world validation data for its multi-cancer detection (MCD) test, which launched as an opt-in component to its Shield colorectal cancer screening offering. The company aims to further hone the assay and is preparing for a potential regulatory submission. The blood-based MCD test uses DNA methylation and detects signals across nine additional cancer types—bladder, breast, esophageal, gastric, liver, lung, ovarian, and pancreatic—along with colorectal. Guardant previously reported retrospective validation results, including 98.5% specificity and 60% sensitivity across the 10 cancer types it detects. Guardant said the ongoing collection acts as a “pre-study” in intended-use settings, allowing it to modify the algorithm before initiating formal prospective studies. The test is also being used in National Cancer Institute’s Vanguard study to evaluate emerging MCED technologies. The effort reflects the push to convert promising clinical readouts into operational performance in routine screening pathways, a key hurdle for MCED adoption and future FDA review.