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French national study: oesophageal cancer after sleeve vs bypass

Risk assessment for esophageal cancer after bariatric surgery: a comparative cohort study between sleeve gastrectomy and gastric bypass.

Overview

Lazzati et al.. Surg Obes Relat Dis 2025 · PMID 39799019 · DOI 10.1016/j.soard.2024.12.002

Oesophageal cancer was rare after both operations (about 4 per 100,000 per year after sleeve) and not significantly different.

Does the study support the specific claim? Partly · Methodological quality: moderate

Study explained simply

What did the researchers want to find out?: Compare cancer risk SG vs GB
How was the study done?: National cohort
How many people, animals or samples were studied?: 370,271
What was actually found?: No significant difference
How large was the observed effect?: HR 1.60 (0.90-2.5)
What do the results mean in everyday life?: Cancer of the gullet after sleeve is rare
What are the study's limitations?: Coding; borderline result
What does it say about Elawady's specific claim?: Contradicts "cancer comes decades earlier"; leaves small uncertainty
Do the results apply to Germany and Europe?: Directly European
What can explicitly not be concluded from this study?: Risk vs no surgery

Authors: Lazzati et al.
Journal: Surg Obes Relat Dis
Year: 2025
Identifier: PMID 39799019 DOI 10.1016/j.soard.2024.12.002
Verification: verified – PubMed efetch 2026-10-26 + Crossref API
Retracted: no
Corrections: none
Extent checked: abstract only
Conflicts of interest and funding: COI statement (PubMed record): Disclosures The authors have no commercial associations that might be a conflict of interest in relation to this article.

Is oesophageal or GEJ cancer more frequent after sleeve gastrectomy than after gastric bypass?

Study design: Cohort study – National hospital discharge database cohort (PMSI), SG vs gastric bypass
Population: Adults undergoing SG or GB in France 2007-2020
Country: France
Period: 2007-2022
Sample size: 370,271 (68.4% SG); ~81,000 followed >=10 y
Inclusion and exclusion criteria: Adults with SG or GB

Exposure / intervention: Sleeve gastrectomy
Comparator: Gastric bypass
Endpoints: Oesophageal and GEJ cancer
Statistical methods: Incidence rates; multivariable Cox; sensitivity analyses

Results: 96 oesophageal cancers (25 GB, 71 SG). Incidence 2.6 (GB) vs 3.9 (SG) per 100,000 person-years; IRR 0.64 (0.40-1.01). Adjusted HR SG vs GB 1.60 (0.90-2.5), P=0.06.
Absolute risks: About 4 oesophageal cancers per 100,000 person-years after SG.
Authors' conclusion: No significant difference in oesophageal/GEJ cancer between SG and GB.

Orienting tool: ROBINS-E
Type of assessment: simplified assessment (abstract only)
Full formal assessment: no
Overall risk of bias: some concerns
Rationale: Administrative data; residual confounding; underpowered for rare outcome.

HR 1.60 (0.90-2.5) is imprecise; a modest excess cannot be excluded.

Shows oesophageal cancer after sleeve is rare and not clearly more frequent than after bypass; also shows uncertainty remains.

Borderline HR.

French national data.

Reassuring on absolute risk; does not exclude a small relative excess.

Multidimensional assessment
Multidimensional assessment
Authenticity of the source	verified
Methodological quality	moderate
Risk of bias	some concerns
Precision of results	low
Directness	direct
Reproducibility	unknown
Consistency with the overall evidence	mixed
Regional transferability	high
Adequacy of the interpretation (by the archive)	not applicable

Follow-up beyond 15 y.