A 58-year-old woman undergoes screening colonoscopy and a 25 mm pedunculated polyp with a thick 8 mm stalk is identified in the sigmoid colon. An endoloop is placed at the stalk base for prophylactic hemostasis. The structure marked **C** (snare positioned at the mid-stalk) is then used to transect the polyp. Why is positioning the snare at the mid-stalk level, rather than at the stalk base or polyp head, the procedurally critical step in this scenario?

Why option 1 is right

Positioning the snare at the mid-stalk is the procedurally critical landmark in pedunculated polyp resection with prophylactic hemostasis. Per ESGE and US Multi-Society Task Force guidance, the snare must be placed at the mid-stalk level to leave sufficient distal stalk below the snare (and below the pre-placed endoloop or hemoclips at the base) to prevent slippage of the hemostatic device, while preserving adequate proximal stalk above the snare for safe retrieval and inspection of the resection base. This balance prevents both hemostatic failure (from loop/clip slippage) and loss of tissue for histopathology. The anchor fact from the clinical scenario is explicit: "a STIFF MONOFILAMENT POLYPECTOMY SNARE is opened and positioned around the POLYP HEAD and gradually closed at the MID-STALK level, leaving sufficient stalk distal to the loop/clips to prevent slippage and proximal stalk for retrieval."

Why each distractor is wrong

Rex DK. Colorectal cancer screening. ACG/USMSTF Guideline 2024. ESGE polyp resection guideline 2022.