Evidence map›Paper›PMID 42118480›Full record

SynthesisClinical & translational oncology : official publication of the Federation of Spanish Oncology Societies and of the National Cancer Institute of Mexico2026

HER2 discordance between primary and metastatic gastric cancer: a systematic review and meta-analysis.

Francisco Cezar Aquino Moraes, Luis Henrique Rios Moreira Rego, Thiago Gorayeb Rebelo, Gustavo Tadeu Freitas Uchôa Matheus, Ana C Melo

Abstract readSystematic ReviewMeta-Analysis
In one paragraph

Synthesis in Clinical & translational oncology : official publication of the Federation of Spanish Oncology Societies and of the National Cancer Institute of Mexico, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

5 authors.

Francisco Cezar Aquino MoraesDepartment of Morphology and Genetics, Federal University of São Paulo, São Paulo, São Paulo, Brazil. francisco.cezar2205@gmail.com.ORCID http://orcid.org/0000-0003-0623-8135
Luis Henrique Rios Moreira RegoState University of Piauí, Teresina, Piauí, Brazil.ORCID http://orcid.org/0009-0003-1604-6759
Thiago Gorayeb RebeloUniversity of Ottawa, Ottawa, ON, Canada.ORCID http://orcid.org/0009-0004-4864-5251
Gustavo Tadeu Freitas Uchôa MatheusFederal University of Triângulo Mineiro, Uberaba, Minas Gerais, Brazil.ORCID http://orcid.org/0009-0005-8707-4823
Ana C MeloDepartment of Pathology and Genomic Medicine, Houston Methodist Hospital, Houston, TX, USA.ORCID http://orcid.org/0000-0002-3274-9636

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

purposeGastric cancer (GC) remains a major global health burden, with poor survival rates. HER2 is a key biomarker for targeted therapy, but discordance between primary tumors and metastases may impact treatment decisions. This meta-analysis evaluated the prevalence and clinical relevance of HER2 status differences between primary gastric cancers and metastatic lesions.

methodsA systematic search of PubMed, Embase, and Cochrane was conducted for studies assessing HER2 status in matched primary and metastatic gastric cancer samples. Pooled proportions and 95% confidence intervals (CIs) were calculated using random-effects models. Subgroup analyses by metastatic site were performed. Statistical analyses were conducted using R software, version 4.2.3.

resultsThis meta-analysis included 3,515 patients across 20 studies. The pooled proportion of HER2-positive expression in primary gastric tumors was 13% (95% CI: 12-15%; I

conclusionsSignificant heterogeneity in HER2 expression between primary and metastatic gastric cancer underscores the need for reassessment of HER2 status in metastatic sites. Relying solely on primary tumor samples may lead to underestimation of HER2 positivity and suboptimal therapeutic decisions. Incorporating site-specific HER2 testing into clinical practice may enhance patient selection for HER2-targeted therapies and improve treatment outcomes.

Indexed as

Biomarkers, TumorErb-b2 Receptor Tyrosine KinasesStomach NeoplasmsHumansNeoplasm MetastasisBiomarkers, TumorERBB2 protein, humanErb-b2 Receptor Tyrosine KinasesGastric cancerHER2 expressionMeta-analysisMetastasis

Identifiers

PMID42118480
PMCPMC13601185

What OpenQuestion holds

Textmetadata
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Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.