Feasibility of Multi-cancer Early Detection Test in Screening Population (NQMD-CS)

This study consists of four stages: recruitment and enrollment, testing and screening, diagnostic evaluation, and follow-up. Approximately 1,250 participants will be recruited through community-based recruitment and invitations from family physicians to enhance the representativeness of the screening population. Peripheral blood will be collected from each participant for blood-based multi-cancer early detection (MCED) testing, which is designed to detect signals associated with five cancer types, including lung, colorectal, liver, gastric, and esophageal cancers. Participants will also undergo usual care and standard single-cancer screening, as appropriate, based on their individual cancer risk assessment. During the diagnostic stage, participants with positive MCED results will undergo diagnostic evaluation guided by the cancer site indicated by the MCED test. Participants with highly suspicious findings from standard screening or usual care will also undergo diagnostic evaluation according to applicable clinical guidelines. The number and types of diagnostic tests and procedures required to achieve diagnostic resolution will be recorded to assess the downstream diagnostic burden and safety of MCED. During the follow-up stage, cancer status will be actively followed. For participants diagnosed with cancer, relevant clinical information will be collected. In addition to the assessment of safety and performance, participant-reported outcome questionnaires will be administered at baseline, upon delivery of screening results, upon completion of the diagnostic evaluation, and at the 1-year follow-up to assess the psychological impact of MCED testing.