This is an observational case-control study to train and validate a genome-wide methylome enrichment platform to detect multiple cancer types and to differentiate amongst cancer types. The cancers included in this study are brain, breast, bladder, cervical, colorectal, endometrial, esophageal, gastric, head and neck, hepatobiliary, leukemia, lung, lymphoma, multiple myeloma, ovarian, pancreatic, prostate, renal, sarcoma, and thyroid. These cancers were selected based on their prevalence and mortality to maximize impact on clinical care. Additionally, the ability of the whole-genome methylome enrichment platform to detect minimal residual disease after completion of cancer treatment and to detect relapse prior to clinical presentation will be evaluated in four cancer types (breast, colorectal, lung, prostate). These cancers were selected based on the existing clinical landscape and treatment availability.