# Multi-Cancer Blood Screening and Mortality

Galleri detects real cancers, but a cancer-mortality benefit remains unestablished; the2026 primary stage endpoint was null and its favorable secondary stageIV result requires clinical follow-up.

The preregistered primary-subclaim rule returns Γ from SC2. Fifty-eight original reports were examined, covering Galleri/other MCED diagnostic work, prospective implementation, real mortality-based single-cancer screening comparators, and separate MRI/DTC pathways. No positive Galleri mortality crossing is counted. The current primary stage endpoint failed and a favorable secondary stageIV signal remains; neither proves a mortality benefit or a mortality null. Weakest-link returns Α from the broad companion claim, while primary-subclaim and scope-matched return Γ. The review preserves genuine detections and legitimate established screening benefits without assigning them to a different assay.

Diagnostic and implementation contexts have been tested, and single-cancer screening outcome boundaries are real. No positive Galleri mortality effect has yet been verified, so these do not map an Ε benefit boundary for the nominal assay. Known-cancer case-control sets, cancer survivors, symptomatic real-world orders, hereditary TP53 surveillance, prenatal abnormal-cfDNA referrals and below50 screening comparators are labelled before outcomes rather than pooled as identical populations.