A bibliometric analysis of immune escape in colorectal cancer: research trends, key contributors, and future directions

The literature for this bibliometric analysis was retrieved from the Web of Science Core Collection, covering the period from January 1, 2015, to December 31, 2024. To minimize discrepancies caused by ongoing updates to the database, all searches were performed on a single day (February 12, 2025). The initial search yielded 597 records. For the purposes of this study, only articles and reviews published in English were included, while other types of publications such as reprints, book chapters, conference abstracts, and news articles were excluded. After applying these inclusion criteria, 573 documents were retained for the analysis, consisting of 383 articles and 190 reviews. The detailed screening process is shown in Figure 1. Boolean operators were utilized to construct the query. The initial broad search was refined through manual screening based on abstracts and titles to include only studies explicitly addressing immune escape mechanisms in CRC, thus ensuring topic specificity. To mitigate bias from incomplete annual data, normalization by monthly averages was considered, and explicit acknowledgment of partial-year inclusion was noted in interpretation. To ensure the accuracy and reliability of the results, two researchers independently conducted the literature search and data collection.

We extracted key data from the selected publications, including journal name, publication year, title, authors, country/region, affiliations, abstract, keywords, and references. Journal impact factor (IF) and Journal Citation Reports (JCR) category were obtained from the Web of Science. The productivity metric was based on citation count. After exporting the data, we performed cleaning by merging duplicates and correcting any spelling errors manually. The cleaned data was then analyzed further. To ensure accuracy and reliability, two authors independently extracted the data.

In this study, we utilized specialized tools including the bibliometrix package (https://www.bibliometrix.org↗) in R software (version 4.4.3), VOSviewer (version 1.6.20), and CiteSpace (version 6.2.R4) to data visualization and analysis (15–17). To ensure data accuracy and reliability, two authors independently conducted the data extraction and analysis, which minimized potential errors and biases, thereby improving the quality and credibility of the study findings.

The current status of immune escape in CRC is illustrated in Figure 2 using R-bibliometrix. The analysis includes publications from 248 journals, with an annual growth rate of 15.93%. A total of 4,104 authors contributed to these publications, with 9 articles authored by a single individual. Articles involving international collaboration accounted for 20.24% of the total. On average, each article had 8.46 authors, 1,441 author keywords, and 39,375 references cited. The average citation lifespan of each paper, from being first noticed to becoming less recognized, was 4.2 years, and each article had been cited an average of 38.08 times.

The analysis of annual publications on immune escape in CRC shows a steady increase in research output over the past decade. The number of publications grew from 23 in 2015 to a peak of 104 in 2023, followed by a slight decline to 87 in 2024. This indicates consistent growth in the volume of research, with the highest publication counts observed in 2023 and 2021, as illustrated in Figure 3. Regarding citation impact, the mean citations per article exhibited considerable fluctuations. In 2015, articles averaged 64.09 citations, which increased to 92.09 in 2018. However, from 2021 onward, citation counts gradually declined, with a significant drop to 3.51 in 2024. The observed citation decline post-2021 may reflect the natural lag in citation accrual. To validate this observation, future studies could incorporate metrics such as citation half-life or field-normalized citation scores to better contextualize recent citation dynamics. As shown in Table 1 and Figure 3.

The bibliometric analysis of source countries reveals significant variations in the distribution of publications related to immune escape in CRC. China leads the field with a substantial margin, contributing 287 articles, which accounts for 50.09% of the total publications. The USA follows with 57 articles (9.95%), while Italy (34 articles, 5.93%), Germany (30 articles, 5.24%), and France (20 articles, 3.49%) round out the top five contributors. Other notable countries include Japan (15 articles, 2.62%), the United Kingdom (12 articles, 2.09%), Australia (11 articles, 1.92%), the Netherlands (10 articles, 1.75%), and Canada (9 articles, 1.57%), as presented in Table 2.

In terms of citation impact, China has an average of 28.40 citations per article. Despite having fewer publications, the USA demonstrates a much higher citation average, with 81.40 citations per article. Germany and Italy also show significant citation impact, with Germany averaging 57.10 citations per article and Italy 40.50 citations per article. These figures indicate that while China dominates in publication volume, countries like the USA and Germany have a higher citation impact per article, reflecting the global influence and visibility of their research contributions. The higher citation impact observed in research from the USA and Germany compared to China may be attributed to stronger international collaboration networks, preferences for publication in journals with wider global readership, and higher engagement in open-access publishing, all of which potentially enhance visibility and influence.

The analysis of institutional contributions identifies the leading institutions in this field. Sun Yat-sen University ranks first with 57 publications, comprising 9.95% of the total, followed closely by Fudan University with 47 articles (8.20%). Université Paris Cité (39 articles, 6.81%) and Central South University (38 articles, 6.63%) rank third and fourth, respectively. The Institut National de la Santé et de la Recherche Médicale (36 articles, 6.28%) ranks fifth, followed by Nanjing Medical University and Shanghai Jiao Tong University, each contributing 35 articles (6.11%). Harvard University, with 29 publications (5.06%), ranks eighth, while Assistance Publique - Hôpitaux de Paris and the German Cancer Research Center, each with 27 publications (4.71%), complete the top ten, as shown in Table 2.

Subsequently, we used VOSviewer to analyze the collaboration network among countries and institutions that published more than five studies. This analysis visualized the relationships based on the number and contacts of publications, creating a collaborative network (Figure 4). Notably, most countries and institutions demonstrate extensive cooperation. The figure also highlights the major publishing years of different countries and institutions, revealing that certain countries or institutions, such as China and Sun Yat-sen University, are emerging as key players in this research domain.

The bibliometric analysis of immune escape in CRC highlights the top ten journals contributing to the literature, with Front Immunol (6.46%), Cancers (5.58%), and Front Oncol (4.01%) being the leading sources. These journals are highly respected in immunology and oncology, all classified in the Q1 quartile based on impact factors. The analysis also identified the most frequently co-cited journals, including Cancer Research (1476 citations, IF 12.5, Q1), Nature (1173 citations, IF 50.5, Q1), and Clinical Cancer Research (1106 citations, IF 10.4, Q1). These journals play a pivotal role in advancing the understanding of immune escape mechanisms in cancer, reflecting the substantial influence of high-impact publications in shaping the current research landscape in this field. As shown in Table 3.

Additionally, we used VOSviewer to analyze and visualize the relationships between journals and co-cited journals. The resulting journal network and co-citation network, depicted in Figure 5, illustrate the active citation interactions among key periodicals in the research on immune escape in CRC. This network visualization highlights the collaborative nature of the field and underscores the centrality of these prominent journals in the ongoing development of this area of study.

The analysis of authorship in the field of immune escape in CRC identifies the top contributors and their key collaborators. Lei Wang leads the field with 7 articles and 238 citations, closely followed by Peter J.K. Kuppen, who has published 6 articles with 212 citations. Prominent co-cited authors include Le, D.T. (128 co-citations) and Galon, J. (92 co-citations), highlighting their significant influence in the area. Additionally, Pornpimol Charoentong stands out with 4 articles and 720 citations, and Wei Wang has contributed 6 articles with 219 citations. Both researchers are frequently co-cited with renowned experts such as Hanahan, D. (88 co-citations) and Overman, M.J. (76 co-citations). The analysis also emphasizes the critical role of collaborative networks, with influential co-cited authors like Topalian, S.L. (72 co-citations) and Siegel, R.L. (72 co-citations) shaping the research direction. As shown in Table 4.

In terms of international collaboration, Figure 6 illustrates the cooperative networks among countries, underscoring the strong academic ties between researchers in China and North America. This map reveals an established and extensive network of cross-border research collaboration, reflecting the global nature of efforts to advance the understanding of immune escape in CRC. Figure 7 highlights the interactions between co-cited authors and articles, reinforcing the importance of international cooperation in tackling the complex challenges presented by immune escape mechanisms in cancer research. These findings suggest that such global partnerships are instrumental in driving progress in this critical area of study.

Using the CiteSpace parameters, a network was generated to visualize the relationships between research topics in the field of immune escape in CRC. The Cluster ID denotes the specific cluster number, with clusters labeled as #0, #1, #2, and so on. The size of each cluster corresponds to the number of publications within it. In Figure 8A, seven distinct clusters were identified, each representing a key research theme, including tumor growth, extracellular vesicles, HLA class, systematic reviews, solid tumor microenvironment, tumor-intrinsic CD47 signaling, and targeting MS4A4A. These clusters encapsulate the central topics in the field, offering insights into the diverse areas of focus within immune escape research. Notably, identified keywords such as CD47 signaling and MS4A4A have direct translational implications, linking fundamental research to ongoing clinical trials in immunotherapy. For instance, targeting CD47 is actively being investigated in clinical trials aiming to overcome immune resistance, underscoring the clinical relevance of these research hotspots. Additionally, Figure 8B presents the close relationships between keywords, as analyzed using VOSviewer.

The Timeline viewer provides insight into the evolving trends of research hotspots by tracking keywords and analyzing the temporal patterns within clusters, illustrating the development of popular research topics over time. Documents grouped in a cluster are placed on a horizontal line, with time moving from left to right, reflecting the significance and volume of research in each field. Figure 9 visually depicts the key research areas and future directions for immune escape in CRC. Figure 10 shows that citing journals primarily come from the fields of Molecular Biology, Immunology, Medicine, and Clinical studies, referred to as research frontiers, while the cited journals are mainly from Molecular Biology and Genetics, forming the knowledge base. The dual-map overlay of journals suggests that the hotspots and frontiers of immune escape in CRC research will increasingly concentrate on Molecular Biology and Immunology.

The original contributions presented in the study are included in the article/supplementary material. Further inquiries can be directed to the corresponding author.