Laparoscopic distal gastrectomy,
does it really help with Noninferior five-year overall survival versus open surgery in clinical stage I gastric cancer?
research showsThe grade is B with 76 points. In the 1,416-participant Korean KLASS-01 trial, five-year overall survival was 94.2% after laparoscopic and 93.3% after open distal gastrectomy, an absolute difference of +0.9 points. The lower bound of the one-sided 97.5% CI was -1.6 points, above the prespecified -5-point noninferiority margin. The hazard ratio was 0.93 with a one-sided 97.5% upper bound of 1.26, inside the prespecified 1.54 limit; the absolute survival difference is reported alongside it. The claim is supported for surgery by skilled surgeons in clinical stage I disease, but one noninferiority trial without independent replication limits the grade to B.
ads claimThe trial did not show that laparoscopy increased cancer survival. It showed that five-year survival was not worse than open surgery beyond the prespecified margin in experienced hands.
Useful facts when choosing a product
- Randomization assigned 705 participants to laparoscopy and 711 to open surgery.
- Five-year cancer-specific survival was also similar at 97.1% versus 97.2%, an absolute difference of -0.03 points.
- The result directly applies to clinical stage I distal gastric cancer treated by experienced surgeons.
Chamgap Semantic Classification Code
Candidate index · review held
P.laparoscopic-distal-gastrectomy.procedural.overall-survival.noninferior.UNKProcedures, devices and tests > Laparoscopic distal gastrectomy > Procedural > overall survival > Noninferiority claim > Unknown
An automated migration candidate, not an issued permanent code; exact claim scope remains under review. This machine-generated migration candidate helps retrieval but is not a permanent assignment. The original verdict ID and URL remain authoritative.
What the research actually shows
KLASS-01 was an open-label randomized noninferiority trial in which 15 surgeons at 13 Korean institutions assigned 1,416 patients with clinical stage I distal gastric adenocarcinoma to laparoscopy, 705, or open surgery, 711. Intention-to-treat analysis established noninferiority and per-protocol analysis was consistent. Overall-survival log-rank P was .64 and median follow-up was 99.8 months. The hazard ratio of 0.93 (one-sided 97.5% upper bound 1.26) is paired with the +0.9-point absolute survival difference. Public funding came from the National Cancer Control Programs of the Republic of Korea Ministry of Health and Welfare, and no conflicts were reported. KLASS-02 concerns advanced gastric cancer; this verdict concerns clinical stage I KLASS-01.
Why this is classified as B (76)
The prespecified -5-point five-year overall-survival margin was met, but this is one noninferiority trial without independent replication, giving a B with 76 points.
Counterpoint. Early recovery and complication advantages are separate outcomes; the primary outcome graded here is five-year overall survival.
Rejudgment record. Cross-check applied — A large publicly funded trial in clinical stage I gastric cancer met the five-year overall-survival noninferiority margin, but it remains one noninferiority trial without independent replication
| Endpoint | H | Hard endpoint - actual events such as death |
| Replication | R1 | Single confirmatory trial |
| Independence | I2 | Decisive evidence is publicly or non-profit funded |
| Effect size | E+ | Meets the clinically important threshold |
Stored derived and displayed grades match; this is not a current recalculation or validity check (B).
Sub-claim grades by effect
This ingredient is marketed for several effects. A single overall grade blends strong and weak claims together, so each effect is graded separately here. The overall grade reflects the strongest disconfirming or core claim.
| Effect (sub-claim) | Grade | Basis |
|---|---|---|
| Noninferior five-year overall survival in clinical stage I gastric cancer | C | The +0.9-point difference had a one-sided lower bound of -1.6 points, above the -5-point margin. |
| Noninferior survival in advanced gastric cancer | ? | Advanced gastric cancer is the question addressed by sister trial KLASS-02 and is outside this verdict. |
Cross-check — AI research and Codex final gate
Evidence Table
| Study | Design | Sample | Funding | Endpoint | Result | Weight |
|---|---|---|---|---|---|---|
| Kim HH et al. 2019 KLASS-01 | Open-label randomized phase 3 noninferiority trial at 13 Korean institutions | 1,416 randomized and analyzed by intention to treat, 705 laparoscopic and 711 open surgery | Public funding from the National Cancer Control Programs of the Republic of Korea Ministry of Health and Welfare; no conflicts reported | Five-year overall survival | 94.2% (95% CI 92.4 to 96.0) versus 93.3% (91.4 to 95.2), absolute difference +0.9 points, one-sided 97.5% lower bound -1.6 points; HR 0.93, one-sided 97.5% upper bound 1.26; meeting the -5-point and HR 1.54 limits. | Large publicly funded hard-outcome trial with direct relevance to Korean practice |
Receipt — 1 References
All 1 cited sources were verified for existence at the original page (as of 2026-08-18).
Final verification and publication gate: Codex · Evidence date: 2026-08-18 · Corrections: none
Cite this verdict
[Chamgap] Benefit of Laparoscopic Distal Gastrectomy for Noninferior 5-Year Survival in Stage I Gastric Cancer — Evidence Grade B·76. 1 cited sources checked. Source: https://chamgap.com/en/verdicts/gut/laparoscopic-distal-gastrectomy-stage-i-gastric-cancer-five-year-survival/ · CC BY 4.0CC BY 4.0 — free to use with attribution; do not distort grades, numbers, or verdict meaning.
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