cfDNA Assay Prospective Observational Validation for Early Cancer Detection and Minimal Residual Disease

This study is testing a blood test that analyzes cell-free DNA (tiny fragments of DNA that float in the bloodstream) to detect cancer early and monitor treatment response. Researchers want to see how well this test can identify various cancers or detect whether cancer has returned after treatment. **You may be eligible if...** - You are 40 or older - You have been recently diagnosed with one of many cancer types (including breast, lung, colon, brain, bladder, cervical, stomach, and others) - OR you have not had cancer in the past 5 years (to serve as a healthy comparison) - You are willing to provide blood samples **You may NOT be eligible if...** - You are currently receiving cancer treatment at the time of enrollment - You are currently taking demethylating medications (a type of cancer drug) - You have been diagnosed with two or more invasive cancers at the same time - You have had any invasive cancer in the last 5 years (in addition to the cancer being studied) - You are known to be pregnant Talk to your doctor to see if this trial is right for you.