Guardant Health announced commercial entry into the multi‑cancer detection (MCD) market with its Shield test and reported Q3 earnings that lifted investor sentiment. The company said use of Shield for colorectal cancer screening is expanding and it intends to gather real‑world adoption data to support broader multi‑cancer screening claims. The move positions Guardant as a prominent liquid‑biopsy player aiming to scale population screening beyond single‑cancer indications. Shield’s real‑world performance data will be critical to payer coverage and clinical adoption. Multi‑cancer blood tests aim to detect multiple tumor types from one blood draw; regulatory, reimbursement, and clinical workflow hurdles remain key gating factors for widespread adoption.