Cohort studyindependent cross-checkabstract checked I-ORG-118 standard review

Cancer after spleen removal in Taiwan

Splenectomy and increased subsequent cancer risk: a nationwide population-based cohort study.

Overview

Sun LM et al.. Am J Surg 2015 · PMID 25986002 · DOI 10.1016/j.amjsurg.2015.01.017

Cancer was more common after splenectomy, especially when the spleen was removed because of disease rather than injury.

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

Study explained simply

What did the researchers want to find out?: Check cancer risk after splenectomy
How was the study done?: National cohort
How many people, animals or samples were studied?: About 4900 patients and matched controls
What was actually found?: HR 2.64 (disease) and 1.29 (trauma)
How large was the observed effect?: HR 1.29-2.64
What do the results mean in everyday life?: Part of the risk is the disease, not the operation
What are the study's limitations?: Confounding; no CIs in abstract
What does it say about Elawady's specific claim?: Partly supports, mostly confounded
Do the results apply to Germany and Europe?: Moderate
What can explicitly not be concluded from this study?: Cannot prove that removing the spleen causes cancer

Authors: Sun LM et al.
Journal: Am J Surg
Year: 2015
Identifier: PMID 25986002 DOI 10.1016/j.amjsurg.2015.01.017
Verification: verified – PubMed efetch 2026-10-26; Crossref works API 2026-10-26
Retracted: no
Corrections: none
Extent checked: abstract only
Conflicts of interest and funding: Non-commercial support (PubMed).

Is splenectomy associated with later cancer risk?

Study design: Cohort study – Nationwide population-based cohort (Taiwan NHIRD), frequency-matched
Population: 2603 non-traumatic and 2295 traumatic splenectomy patients plus 4 matched controls each
Country: Taiwan
Period: Not stated in abstract
Sample size: 4898 splenectomised; about 19,600 controls
Inclusion and exclusion criteria: Splenectomy recorded in claims

Results: Adjusted HR for overall cancer 2.64 (non-traumatic) and 1.29 (traumatic); higher risks of certain gastrointestinal, head and neck and haematological cancers, more prominent after non-traumatic splenectomy.
Absolute risks: Not reported in abstract.
Authors' conclusion: People with splenectomy have higher risks of overall and site-specific cancers, especially after non-traumatic splenectomy.

Orienting tool: ROBINS-E
Type of assessment: simplified assessment (abstract only)
Full formal assessment: no
Overall risk of bias: high
Rationale: Non-traumatic splenectomy is often done for haematological disease, which itself predisposes to haematological cancers.

The much smaller HR after traumatic splenectomy (1.29) than after non-traumatic (2.64) suggests that most of the excess reflects underlying disease.

Tests the cancer part of C-ORG-13.

Indication confounding; Kristinsson (A-ORG-16) similar limitations.

Asian population; biology transferable, confounding similar.

Weak support for a modest cancer excess after traumatic splenectomy; most of the larger excess is likely explained by the underlying disease.

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

CIs and absolute risks.