Non-invasive early detection of cancer four years before conventional diagnosis using a blood test
Late stage cancers often have worse survival outcomes; survival rates increase significantly when cancer is identified at early stages. However, most cancer types currently lack an effective non-invasive early screening option. In the Taizhou Longitudinal Study (TZL), 123,115 healthy subjects provided plasma samples for long-term storage and were then monitored for cancer occurrence. They used PanSeer, a noninvasive blood test based on circulating tumor DNA methylation, on TZL plasma samples from 605 asymptomatic individuals. Of whom, 191 were later diagnosed with stomach, esophageal, colorectal, lung or liver cancer within four years of blood draw. They also assayed plasma samples from an additional 223 cancer patients, plus 200 primary tumor and normal tissues, and found that PanSeer detects five common types of cancer in 88% of post-diagnosis patients with a specificity of 96%. Furthermore, PanSeer could detect cancer in 95% of asymptomatic individuals who were later diagnosed. A non-invasive test for early detection of cancer, such as PanSeer, has great potential for implementation in primary care. Though longitudinal studies are required to confirm these results, future studies could explore optimal methods of implementing PanSeer in primary care to improve early cancer detection.