Definition and research guide
This page combines a MeSH definition, publication statistics and selected research abstracts. It is a starting point for reading the literature, not a medical textbook or a systematic evidence review.
Content available: 4 complete abstracts (792 words), 10 references. Full article text is not stored or reproduced here; follow the PMID, DOI or PMC links to read the original sources and their access terms.
Definition
A membrane in the midline of the thorax of mammals. It separates the lungs between the sternum in front and the vertebral column behind. It also surrounds the heart, trachea, esophagus, thymus, and lymph nodes.
Definition: NLM Medical Subject Headings (MeSH) scope note (Public domain (U.S. National Library of Medicine); attribution requested). View the MeSH record.
Where it fits in the MeSH classification
- Broader topics
- Thoracic Cavity
- See also
- Mediastinoscopy; Pneumomediastinum, Diagnostic
Related concepts
- Thorax
- Sternum
- Vertebral Column
- Heart
- Trachea
- Esophagus
- Thymus
- Lymph Nodes
Research landscape
PubMed indexes 11,182 records tagged with the MeSH heading “Mediastinum” (counts retrieved 2026-10-31). 1,438 of them (12.9%) were published from 2020 onward, and the busiest period so far is through 1999 with 5,841 records.
Reviews account for 839 records (7.5%) and meta-analyses for 43. Randomized controlled trials number 127 (1.1%) as a share of all records on the topic. Randomized trials make up only a small share of this literature, so much of what is known comes from laboratory, observational or descriptive work.
Show the data
| Period | Records |
|---|---|
| through 1999 | 5,841 |
| 2000-2009 | 1,590 |
| 2010-2019 | 2,313 |
| 2020 onward | 1,438 |
Publication-type chart data
| Type | Records | Share |
|---|---|---|
| Reviews | 839 | 7.5% |
| Meta-analyses | 43 | 0.4% |
| Randomized controlled trials | 127 | 1.1% |
Method: PubMed query "Mediastinum"[MeSH Terms] with publication-type and date filters, retrieved 2026-10-31.
Reading the evidence in anatomy and physiology
Anatomy describes how body structures are built and physiology describes how they normally work, so most findings here are descriptive or mechanistic rather than evidence about treatment. Much of what is known comes from dissection, imaging, tissue studies and experiments in animals, and measurements in healthy volunteers can differ from those in people with disease or at different ages. Normal ranges vary between individuals and populations. Check whether a result was measured in people or in another species, the age and health of the participants, and the method used.
Evidence from open-access studies
These open-access studies come from PubMed’s best-match results for this heading (papers whose main topic it is), ranked here by citation count, with one recent addition. Each abstract is reproduced in full under its recorded open licence so that you can read the authors’ own words. They illustrate the literature; they are not a systematic summary of it. Citation counts measure attention, not reliability or clinical benefit.
| Study / authors | Year | Source label / design | Europe PMC citations | Licence / source |
|---|---|---|---|---|
| Multicenter cross-calibration of I-123 metaiodobenzylguanidine heart-to-mediastinum ratios to overcome camera-collimator variations | 2014 | Research article Design not recorded in structured metadata | 103 | cc by PMID 24942608 · DOI · PMC4167440 |
| Mediastinal lymph node dissection versus mediastinal lymph node sampling for early stage non-small cell lung cancer: a systematic review and meta-analysis | 2014 | Meta-analysis Design not recorded in structured metadata | 49 | cc by PMID 25296033 · DOI · PMC4190366 |
| Mesenchymal tumours of the mediastinum--part I | 2015 | Review article Design not recorded in structured metadata | 33 | cc by PMID 26358059 · DOI · PMC4656709 |
| The Landmark Series: Advances in Preoperative Mediastinal Lymph Node Staging for Non-small Cell Lung Cancer (NSCLC) | 2025 | Review article Design not recorded in structured metadata | 13 | cc by PMID 40025361 · DOI · PMC11976788 |
Multicenter cross-calibration of I-123 metaiodobenzylguanidine heart-to-mediastinum ratios to overcome camera-collimator variations [1]
Abstract reading summary — source excerpts
- Opening excerpt
- BackgroundThe heart-to-mediastinum ratio (HMR) of (123)I-metaiodobenzylguanidine (MIBG) showed variations among institutions and needs to be standardized among various scinticamera-collimator combinations.
- Closing excerpt
- 83, P ConclusionBy using the reference HMR and conversion coefficients for the system, HMRs with various conditions can be converted to the standard HMRs in a range of normal to low HMRs.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (205 words)
BackgroundThe heart-to-mediastinum ratio (HMR) of (123)I-metaiodobenzylguanidine (MIBG) showed variations among institutions and needs to be standardized among various scinticamera-collimator combinations.MethodsA total of 225 phantom experiments were performed in 84 institutions to calculate cross-calibration coefficients of HMR. Based on phantom studies, a conversion coefficient for each camera-collimator system was created, including low-energy (LE, n = 125) and a medium-energy (ME, n = 100) collimators. An average conversion coefficient from the most common ME group was used to calculate the standard HMR. In clinical MIBG studies (n = 52) from three institutions, HMRs were standardized from both LE- and ME-type collimators and classified into risk groups of ResultsThe average conversion coefficients from the individual camera-collimator condition to the mathematically calculated reference HMR ranged from 0.55 to 0.75 for LE groups and from 0.83 to 0.95 for ME groups. The conversion coefficient of 0.88 was used to unify HMRs from all acquisition conditions. Using the standardized HMR, clinical studies (n = 52) showed good agreement between LE and ME types regarding three risk groups (κ = 0.83, P ConclusionBy using the reference HMR and conversion coefficients for the system, HMRs with various conditions can be converted to the standard HMRs in a range of normal to low HMRs.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 24942608 · DOI · PMC4167440
Mediastinal lymph node dissection versus mediastinal lymph node sampling for early stage non-small cell lung cancer: a systematic review and meta-analysis [2]
Abstract reading summary — source excerpts
- Opening excerpt
- ObjectiveThis systematic review and meta-analysis aimed to evaluate the overall survival, local recurrence, distant metastasis, and complications of mediastinal lymph node dissection (MLND) versus mediastinal lymph node sampling (MLNS) in stage I-IIIA non-small cell lung cancer (NSCLC) patients.
- Closing excerpt
- Whether or not MLND is superior to MLNS for stage II-IIIA remains to be determined.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (278 words)
ObjectiveThis systematic review and meta-analysis aimed to evaluate the overall survival, local recurrence, distant metastasis, and complications of mediastinal lymph node dissection (MLND) versus mediastinal lymph node sampling (MLNS) in stage I-IIIA non-small cell lung cancer (NSCLC) patients.MethodsA systematic search of published literature was conducted using the main databases (MEDLINE, PubMed, EMBASE, and Cochrane databases) to identify relevant randomized controlled trials that compared MLND vs. MLNS in NSCLC patients. Methodological quality of included randomized controlled trials was assessed according to the criteria from the Cochrane Handbook for Systematic Review of Interventions (Version 5.1.0). Meta-analysis was performed using The Cochrane Collaboration's Review Manager 5.3. The results of the meta-analysis were expressed as hazard ratio (HR) or risk ratio (RR), with their corresponding 95% confidence interval (CI).ResultsWe included results reported from six randomized controlled trials, with a total of 1,791 patients included in the primary meta-analysis. Compared to MLNS in NSCLC patients, there was no statistically significant difference in MLND on overall survival (HR = 0.77, 95% CI 0.55 to 1.08; P = 0.13). In addition, the results indicated that local recurrence rate (RR = 0.93, 95% CI 0.68 to 1.28; P = 0.67), distant metastasis rate (RR = 0.88, 95% CI 0.74 to 1.04; P = 0.15), and total complications rate (RR = 1.10, 95% CI 0.67 to 1.79; P = 0.72) were similar, no significant difference found between the two groups.ConclusionsResults for overall survival, local recurrence rate, and distant metastasis rate were similar between MLND and MLNS in early stage NSCLC patients. There was no evidence that MLND increased complications compared with MLNS. Whether or not MLND is superior to MLNS for stage II-IIIA remains to be determined.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 25296033 · DOI · PMC4190366
Mesenchymal tumours of the mediastinum--part I [3]
Abstract reading summary — source excerpts
- Opening excerpt
- The mediastinum is an anatomically defined space in which organs and major blood vessels reside with surrounding soft tissue elements.
- Closing excerpt
- In 1963, Pachter and Lattes systematically reviewed soft tissue pathology of the mediastinum, covering the hitherto described [2, 226, 227] In this review, based on the 2013 WHO classification of soft tissue tumours and the 2015 WHO classification of tumours of the lung, pleura, thymus and heart, we provide an updated overview of mesenchymal tumours that may be encountered in the mediastinum.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (133 words)
The mediastinum is an anatomically defined space in which organs and major blood vessels reside with surrounding soft tissue elements. The thymus is an important organ in the mediastinum, and many of the masses encountered in the mediastinum are related to this organ. Most neoplasms diagnosed in the mediastinum are epithelial tumours (thymomas and thymic carcinomas), lymphomas or germ cell tumours. In contrast, soft tissue tumours of the mediastinum are rare. In 1963, Pachter and Lattes systematically reviewed soft tissue pathology of the mediastinum, covering the hitherto described [2, 226, 227] In this review, based on the 2013 WHO classification of soft tissue tumours and the 2015 WHO classification of tumours of the lung, pleura, thymus and heart, we provide an updated overview of mesenchymal tumours that may be encountered in the mediastinum.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 26358059 · DOI · PMC4656709
The Landmark Series: Advances in Preoperative Mediastinal Lymph Node Staging for Non-small Cell Lung Cancer (NSCLC) [4]
Abstract reading summary — source excerpts
- Opening excerpt
- Accurate mediastinal staging is essential for determining the extent of lung cancer, predicting prognosis, and guiding treatment strategies.
- Closing excerpt
- This review examines five key trials that explore the expanding role of endobronchial and endoscopic techniques in mediastinal staging for non-small cell lung cancer, demonstrating how these advancements have transformed the diagnostic landscape.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (176 words)
Accurate mediastinal staging is essential for determining the extent of lung cancer, predicting prognosis, and guiding treatment strategies. Current clinical guidelines recommend preoperative invasive mediastinal staging for most patients with potentially resectable lung cancer, as imaging modalities alone often lack sensitivity and specificity. Invasive mediastinal staging techniques are categorized into surgical (e.g., cervical mediastinoscopy, video-assisted thoracic surgery) and nonsurgical (i.e., minimally invasive) approaches. Although cervical mediastinoscopy has historically been the gold standard, minimally invasive techniques have gained prominence in recent decades. These approaches, including endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA), endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA), and combined EBUS/EUS, provide improved accuracy and reduced morbidity compared with traditional surgical methods. EBUS-TBNA facilitates access to a broad range of lymph node stations with real-time ultrasound guidance, while EUS-FNA complements EBUS by enabling transesophageal lymph node sampling. Together, these techniques enable a more comprehensive mediastinal staging. This review examines five key trials that explore the expanding role of endobronchial and endoscopic techniques in mediastinal staging for non-small cell lung cancer, demonstrating how these advancements have transformed the diagnostic landscape.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 40025361 · DOI · PMC11976788
Key reviews and meta-analyses
The most cited review-type papers among PubMed’s best-match results for this heading, listed with bibliographic details only. Follow the links for the full text and access terms.
- Research article Invasive mediastinal staging of lung cancer: ACCP evidence-based clinical practice guidelines (2nd edition) [5]
- Research article Radiation-associated cardiovascular disease [6]
- Research article Test performance of endobronchial ultrasound and transbronchial needle aspiration biopsy for mediastinal staging in patients with lung cancer: systematic review and meta-analysis [7]
- Research article Congenital anomalies of the tracheobronchial tree, lung, and mediastinum: embryology, radiology, and pathology [8]
- Research article Mediastinal fibrosis complicating histoplasmosis [9]
- Research article Radiation-associated valvular disease [10]
References
- Nakajima K, Okuda K, Yoshimura M, Matsuo S, Wakabayashi H, Imanishi Y, et al.. Multicenter cross-calibration of I-123 metaiodobenzylguanidine heart-to-mediastinum ratios to overcome camera-collimator variations. . 2014. PMID 24942608 · DOI · PMC4167440
- Huang X, Wang J, Chen Q, Jiang J. Mediastinal lymph node dissection versus mediastinal lymph node sampling for early stage non-small cell lung cancer: a systematic review and meta-analysis. . 2014. PMID 25296033 · DOI · PMC4190366
- den Bakker MA, Marx A, Mukai K, Ströbel P. Mesenchymal tumours of the mediastinum--part I. . 2015. PMID 26358059 · DOI · PMC4656709
- Baskin AS, Burapachaisri K, Guha S, Velotta JB. The Landmark Series: Advances in Preoperative Mediastinal Lymph Node Staging for Non-small Cell Lung Cancer (NSCLC). . 2025. PMID 40025361 · DOI · PMC11976788
- Detterbeck FC, Jantz MA, Wallace M, Vansteenkiste J, Silvestri GA, American College of Chest Physicians. Invasive mediastinal staging of lung cancer: ACCP evidence-based clinical practice guidelines (2nd edition). Chest. 2007. PMID 17873169 · DOI
- Adams MJ, Hardenbergh PH, Constine LS, Lipshultz SE. Radiation-associated cardiovascular disease. Crit Rev Oncol Hematol. 2003. PMID 12482572 · DOI
- Adams K, Shah PL, Edmonds L, Lim E. Test performance of endobronchial ultrasound and transbronchial needle aspiration biopsy for mediastinal staging in patients with lung cancer: systematic review and meta-analysis. Thorax. 2009. PMID 19454408 · DOI
- Berrocal T, Madrid C, Novo S, Gutiérrez J, Arjonilla A, Gómez-León N. Congenital anomalies of the tracheobronchial tree, lung, and mediastinum: embryology, radiology, and pathology. Radiographics. 2004. PMID 14610245 · DOI
- Loyd JE, Tillman BF, Atkinson JB, Des Prez RM. Mediastinal fibrosis complicating histoplasmosis. Medicine (Baltimore). 1988. PMID 3045478 · DOI
- Carlson RG, Mayfield WR, Normann S, Alexander JA. Radiation-associated valvular disease. Chest. 1991. PMID 1995208 · DOI
About this article
- Sources
- NLM Medical Subject Headings (definition, synonyms); NCBI PubMed (counts, identifiers); Europe PMC (open-access abstracts and citation counts).
- Verification
- Every reference was resolved against PubMed on 2026-10-31; title, year and DOI matched.
- Review state
- automated source verified; no human expert review has been recorded yet.
- Version
- 1, last updated 2026-10-31.
See how EvidenceLib is built. Spotted an error? Email support@evidencehelix.com.
Evidence strength
EvidenceHelix's computed view of the study designs behind this topic: how common meta-analyses, randomized trials and reviews are, how recent the literature is, and a plain-language reading. It describes the design mix of the literature. It is not a quality appraisal of any study, and it is not medical advice.