← Issue №1/ week of Jun 24, 2026/Colorectal

Inter and intra-observer agreement for the LST Classification in Large (>2cm) Colorectal Laterally Spreading Tumours.

From GI Signals issue №1: what this paper found, what it changes, and where it sits against the current standard of care, reviewed by Simon Mathews, MD.

Colorectal prospective cohort · n=46 · Jun 30, 2026 · Am J Gastro · IF 14.9

Inter and intra-observer agreement for the LST Classification in Large (>2cm) Colorectal Laterally Spreading Tumours.

Basic science
Clinical takeawayThe full LST subtype system has only fair inter-observer reliability (kappa about 0.36) versus moderate (about 0.48) for a simplified granular vs non-granular split, so weight the reproducible split but still document the high-risk nodular-mixed and pseudodepressed features, since guidelines use them to select en-bloc resection or ESD.
What it foundInter-observer agreement for LST classification was poor (κ=0.37 first round, κ=0.36 second round), improving to moderate (κ≈0.48) with a simplified 3-category granular vs non-granular model.
ContextChallenges current reliance on detailed LST subclassification, which lacks standardized reliability despite widespread use in predicting submucosal invasion risk and resection strategy.
Measured against the standard of care· USMSTF 2017 (Rex et al., Gastroenterology) + USMSTF 2022 focused update on age (Patel et al., Gastroenterology 2022;162:285-299) / ACS 2026 (CA Cancer J Clin)

Decision at stakethe morphological assessment of large colorectal laterally spreading tumors for predicting submucosal invasion risk

No single passage of this standard matched the paper closely enough to quote, so none is shown. The standard is cited above.

Our full summary of this standard

U.S. Multi-Society Task Force (2017 guideline, revised by the 2022 focused update on age to start and stop): offer average-risk colorectal cancer screening to everyone aged 45-75. Screening at 45-49 is a weaker recommendation than at 50-75. Colonoscopy every 10 years and annual FIT are the Tier 1 cornerstones. Tier 2 alternatives are multi-target stool DNA every 3 years, CT colonography every 5 years, and flexible sigmoidoscopy every 5-10 years. Capsule colonoscopy every 5 years is Tier 3. Any abnormal non-colonoscopy test requires a diagnostic colonoscopy, and a stool test should not be offered to a patient who would decline follow-up colonoscopy. Patients who are up to date with negative prior screening, particularly a high-quality colonoscopy, may consider stopping at 75 or when life expectancy is under 10 years. Decisions at 76-85 are individualized by health and prior screening, and screening after 85 is not recommended. The American Cancer Society's May 2026 guideline agrees on the 45-75 range, no screening after 85, and colonoscopy as the preferred option. It adds the next-generation mt-sDNA test and the multitarget stool RNA test (ColoSense), both every 3 years, and it adds an FDA-approved blood-based cfDNA test (Shield) only for people who decline or do not complete visual or stool screening. ACS says a positive stool or blood test should be followed by colonoscopy, preferably within 6 months. The 2026 ASGE paper on follow-up after an abnormal stool test is an implementation review (navigation, tracking, direct-access colonoscopy), not a new screening guideline.

USMSTF 2017 (Rex et al., Gastroenterology) + USMSTF 2022 focused update on age (Patel et al., Gastroenterology 2022;162:285-299) / ACS 2026 (CA Cancer J Clin) · reviewed 2026-10-11 ↗
Djinbachian R … Pioche M · American Journal of Gastroenterology · IF 14.9 · PubMed ↗Permalink
← Read the whole of issue №1 Every paper GI Signals surfaces gets a page like this one. All issues