This study collects blood and tissue samples from patients with cancer and without cancer to evaluate tests for early cancer detection. Collecting and storing samples of blood and tissue from patients with and without cancer to study in the laboratory may help researchers develop tests for the early detection of cancers.

PRIMARY OBJECTIVE: I. To provide a blinded reference set of cancer versus (vs.) non-cancer blood samples that will be used to validate assays for inclusion in a prospective clinical trial focused on utility of blood-based multi-cancer early detection. SECONDARY OBJECTIVES: I. Evaluate test performance at the time of initial cancer diagnosis by tumor type. II. Evaluate test performance at the time of initial cancer diagnosis by clinical stage. OUTLINE: Participants complete a questionnaire at baseline. Participants undergo collection of blood samples at registration and at 12 months after registration. Patients with a cancer diagnosis may undergo collection of tissue samples at registration and 12 months after registration. After completion of study, participants are followed up at 1 year.