Evidence map›Paper›PMID 41723389›Full record

SynthesisBMC cancer2026

Gut microbial signatures and immunotherapy outcomes in NSCLC and melanoma: a systematic review and meta-analysis.

Mohammed Elmujtba Adam Essa, Hamid Noori, James Butler, Abdelkareem A Ahmed

Abstract readSystematic ReviewMeta-Analysis
In one paragraph

Synthesis in BMC cancer, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing 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

1 citing paper in PubMed.

  1. Review
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

4 authors.

Mohammed Elmujtba Adam EssaDepartment of clinical Medicine, Medical and Cancer Research Institute, Nyala, Sudan. Awadali818@yahoo.com.
Hamid NooriDepartment of clinical Neuroscience, University of Oxford, Oxford, UK.
James ButlerDepartment of General Surgery, South Infirmary Victoria University Hospital, Cork, Ireland.
Abdelkareem A AhmedDepartment of clinical Medicine, Medical and Cancer Research Institute, Nyala, Sudan.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundThe composition of the gut microbiome has been linked to clinical responses to immune checkpoint inhibitors (ICIs), but its prognostic association with outcomes in non-small cell lung cancer (NSCLC) and melanoma remains incompletely defined. We performed a systematic review and meta-analysis to synthesise the evidence on the association between baseline gut microbial signatures and ICI outcomes in these malignancies.

methodsFollowing PRISMA guidelines, we searched PubMed, Embase, Web of Science, and Scopus through April 2025 for studies correlating baseline gut microbiota with overall survival (OS), progression-free survival (PFS), objective response rate (ORR), or immune-related adverse events (irAEs) in patients with NSCLC or melanoma receiving ICIs. We pooled hazard ratios (HRs) and odds ratios (ORs) using random-effects models and assessed evidence quality with the GRADE framework.

resultsWe included 26 studies comprising 1,542 patients. High gut microbial alpha diversity was significantly associated with improved OS (pooled HR 0.52, 95% CI 0.41–0.66) and PFS (pooled HR 0.58, 95% CI 0.47–0.71). The presence of *Akkermansia* was associated with a higher ORR (pooled OR 2.15, 95% CI 1.38–3.35). Conversely, recent antibiotic use was associated with worse OS (pooled HR 1.72, 95% CI 1.34–2.21). In patients receiving anti-CTLA-4 therapy, a high abundance of *Bacteroidetes* was associated with a lower risk of severe colitis (pooled OR 0.34, 95% CI 0.18–0.64). The overall certainty of evidence was rated as moderate for most outcomes.

conclusionBaseline gut microbiome features, particularly high diversity and the presence of specific commensal taxa, are moderately associated with superior clinical outcomes to ICIs in NSCLC and melanoma. Our findings suggest that the gut microbiome could serve as a useful prognostic biomarker and may sooner or later be modulated to increase ICI efficacy.

Indexed as

Carcinoma, Non-Small-Cell LungGastrointestinal MicrobiomeImmune Checkpoint InhibitorsImmunotherapyLung NeoplasmsMelanomaHumansPrognosisTreatment OutcomeImmune Checkpoint InhibitorsAkkermansiaFaecalibacteriumgut microbiomeimmune checkpoint inhibitorsmelanomaNSCLC

Identifiers

PMID41723389
PMCPMC12980955

What OpenQuestion holds

Textmetadata
LicenceCC BY-NC-ND
Read underepoch 390

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.