Analysis of tumor treatment under interventional ultrasound through structural and temporal dynamics: a bibliometric visualization

Introduction

Following closely behind cardiovascular diseases, cancer is the second leading cause of death worldwide, and claims the lives of 9.6 million people annually (1,2). The total number of deaths due to cancer far surpasses the total number of deaths due to acquired/primary immunodeficiency syndrome, tuberculosis, and malaria combined (1,2). China and the United States, as the largest developing and developed countries, respectively, are also the two countries with the highest number of cancer patients (3,4). As understandings of the occurrence and molecular mechanisms of cancer improve, approaches for treating cancer also continue to evolve (5,6). Extensive research has helped to unravel the molecular mechanisms of tumors and to develop targeted therapies; however, challenges still arise in the provision of personalized treatment drugs (7-10). Therefore, in addition to the advancement of precision-targeted therapies, it is also essential to consider technological breakthroughs in traditional treatment methods such as surgery.

Over the past few decades, real-time guidance has transformed ultrasound from a diagnostic tool to an interventional procedure. Interventional ultrasound employs direct methods (e.g., ultrasound-guided tumor ablation surgery) and indirect methods (e.g., the injection of anti-tumor agents). In indirect methods, external imaging is used to guide the injection delivery of drugs that can stimulate the patient’s immune system to target the tumor, or chemotherapy drugs with localized effects. This method has a delayed anti-tumor effect (11).

Currently, commonly used tumor ablation techniques include radiofrequency ablation (RFA), microwave ablation (MWA), laser ablation (LA), high-intensity focused ultrasound (HIFU), photodynamic therapy, and sonodynamic therapy (SDT) (12-15). Compared to traditional open surgery, these techniques result in less trauma and fewer severe systemic side effects, reducing the risks associated with treatment (16,17). Tumor ablation techniques rely on different imaging modalities, such as ultrasound, fluoroscopy, computed tomography, and magnetic resonance imaging, to help doctors accurately locate tumors and destroy tumor tissue through chemical or thermal therapy, achieving the complete eradication or substantial destruction of tumors (18,19). Whether used as an imaging tool or as an ablation tool, ultrasound has a number of unique advantages in terms of no radiation, real-time imaging, cost-effectiveness, and convenience (20).

Previous studies have examined the use of endoscopic ultrasound (EUS) in the treatment of tumors. For example, one study reported that as an adjunct therapy for pancreatic cancer, EUS-guided RFA may be more effective than chemotherapy alone (21). Additionally, a multicenter study emphasized the safety and high success rate of placing fiducial markers under EUS guidance for rectal and esophageal tumors, reporting no adverse events and a short procedure time (22). The safety and efficacy of EUS-guided tumor ablation surgery has been experimentally assessed at various stages using traditional endoscopic ultrasound fine-needle aspiration (EUS-FNA) methods or their modified versions. The application of EUS in RFA is more beneficial than the percutaneous approach, especially for anatomical locations that are difficult to visualize or reach (11,23). EUS-FNA can also be employed in various interventional procedures for both benign and malignant lesions, such as pseudocyst drainage, the delivery of chemotherapy drugs, and ethanol injections for liver cancer (11).

Additionally, interventional oncologists use contrast-enhanced ultrasound (CEUS) for image guidance during the thermal ablation process, as it can depict real-time tumor perfusion dynamics, and intraoperative ultrasound contrast can identify precise ablation targets (24). Thousands of articles related to this field have been published in various academic journals and CEUS has been applied in the treatment of various cancers, including liver cancer, prostate cancer, breast cancer, and pancreatic cancer (12,25-27). Several studies have shown that the efficacy of tumor ablation techniques is comparable to traditional surgical resection for specific types of tumors (28,29), particularly in the treatment of early stage hepatocellular carcinoma patients, where ablation techniques are considered the optimal treatment choice and may become a first-line alternative treatment for extremely early stage patients (30). Further, unlike systemic chemotherapy, drug delivery guided by ultrasound exerts a localized anti-tumor effect, which is particularly important for patients with localized diseases.

In recent years, SDT has rapidly developed as an emerging non-invasive cancer treatment modality. SDT involves the simultaneous application of low-frequency ultrasound and sonosensitizers, resulting in the generation of reactive oxygen species, and causing cell damage and even death. Currently, SDT is widely applied in various tumors, such as liver cancer, pancreatic cancer, and breast cancer (31-33). This treatment method typically involves activating drugs to overcome immune suppression, achieving effective deep-tissue SDT in primary tumors. There are also reports on the efficacy of SDT in metastatic tumors (34,35).

Bibliometrics is a research method used to quantitatively analyze the characteristics of scientific literature and determine which countries/regions, institutions, authors, journals, and publications have had the greatest impact in a particular field. It aims to identify current research hotspots and future trends by constructing research collaboration networks (36). This research method has been widely applied across various academic disciplines (37-39). In this study, more than 60 years of publications and knowledge related to the field of tumor treatment under interventional ultrasound were collected and analyzed. We aimed to examine the evolution of this field, identify trends in research hotspots, and reveal current cutting-edge issues and future research directions. This study not only provides a historical context for research on interventional ultrasound for tumor treatment but also examines the main research forces and development dynamics in this field. Based on our analyses, our findings may contribute to advancements in the application of interventional ultrasound technology in tumor treatment.

Methods

Search strategy and data collection

The Web of Science Core Collection (WoSCC) is the most commonly used database in bibliometric analysis. It contains a vast amount of scientific publications, and serves as the primary source of statistical data for bibliometric software. Our search of the WoSCC database was conducted on October 19, 2023. To minimize bias resulting from database updates, all searches were performed on one day, and the data were downloaded in “Full Record and Cited References” and “Plain Text” formats. For our search strategy, we used a broad set of terms with the following formula: Topic Search = ((Cancer OR Neoplasms OR Tumor OR Carcinoma OR Malignancies) AND (“Ultrasound Ablation” OR “Ultrasound Therapy” OR “Ultrasound Intervention” OR “Interventional, Ultrasound” OR “Ultrasound Treatment”)).

Inclusion and exclusion criteria

We downloaded all the relevant literature published between 1960 and 2023 that met the search criteria. We the categorized the retrieved literature, distinguishing them by document type. We also thoroughly checked for duplicates to ensure the uniqueness of the data. After excluding certain types of documents (e.g., reprints, retractions, and corrections), articles that met our inclusion criteria were retained. Additionally, we further verified the accessibility of these documents to ensure that all literature included in the study was accessible, providing a reliable foundation for the subsequent analysis.

Analysis methods

Microsoft Excel 2022 was used to manage the data and create bar charts in this study. Bibliometrix (version 4.1.4), which is an open-source tool based on the R programming language, was used to conduct a comprehensive bibliometric analysis (40). The online tool Biblioshiny was used to calculate the global citation counts for authors and articles. VOSviewer (version 1.6.19) is a bibliometric analysis program that was used for the co-occurrence analysis of countries/regions, institutions, authors, and keywords (41). The data were imported from pure text files sourced from the WoSCC. In VOSviewer, the size of the nodes reflects the quantity or co-occurrence frequency of the research, while the size of the links indicates the co-occurrence frequency between two nodes; nodes of the same color represent the same cluster. Collaboration networks of countries/regions and institutions were based on the analysis results in VOSviewer, the merging of the same keywords was manually executed, and adjustments and modifications were made using Scimago Graphica (version 1.0.36) and Microsoft Charticulator 2023. CiteSpace (version 6.1.R6 Advanced) is a Java application that was used to visualize the collaboration networks in this research field and the evolution of research trends (42). CiteSpace was employed to conduct the keyword and source journal analyses in this research field, including the co-occurrence analysis, timeline analysis, burst analysis, and journal dual-map overlay analysis.

Results

Global trends and annual overview of publications

In total, we downloaded 2,605 articles, and verified that there were no duplicate entries. After excluding certain types of records (e.g., reprints, retractions, and corrections), a total of 2,588 articles remained. The quantitative description and feature evaluation of the literature were mainly based on the following four aspects: global publication trends, institutions and authors, source journals and citations, and research hotspots. Various software tools were used for the analysis (Figure 1A).

Figure 1 Global trends in research on tumor treatment under interventional ultrasound. (A) The workflow of this study. (B) The number of publications per year, and the cumulative number of publications per year. (C) The top 10 countries/regions with the highest number of publications. (D) The top 10 countries/regions with the highest total citations. (E) Heatmap of the temporal distribution of the publication trends for various countries/regions. (F) Map of collaboration networks between countries/regions. TS, topic search.

The bar chart shows the temporal distribution of annual publications by year (Figure 1B). Over the past 63 years, there has been a steady increase in the number of articles published in this field. In the early stages of development in this field, reports were largely published sporadically. During the slow development period from 1960 to 2000, the total number of articles was less than 200, indicating that researchers paid relatively little attention to this area during that time. In the stable development period of this field from 2001 to 2015, there was an upward trend in the number of publications, amounting to over 1,000 relevant publications in 15 years. In the fast growth phase from 2016 to 2023, the trend of increasing annual publications was the most pronounced, amounting to 1,345 publications over 8 years, surpassing the total of all previous years.

We also analyzed the distribution of research on tumor treatment under interventional ultrasound in different countries/regions. A total of 66 countries/regions worldwide have conducted research in this field. A bar chart displays the number of articles from each countries/regions (Figure 1C). Notably, China and the United States have been particularly active in this research field with 646 and 358 publications, respectively, followed by Germany (n=114), Japan (n=107), Canada (n=106), and Italy (n=97). Notably, while the number of publications from the United Kingdom (n=86) and France (n=82) is lower, they have been cited far more than the four countries mentioned above, second only to China and the United States (Figure 1D). Turkey, Romania, and Austria began their research in this field early, but their involvement was relatively short lived. China, the United States, and the United Kingdom, although starting slightly later than these countries, have shown a pattern of gradual and sustained development, contributing to a large number of publications to some extent (Figure 1E). These results indicate that both China and the United States are in the leading positions and play crucial roles in current research. Additionally, Europe, Canada, Japan, and other countries/regions have had significant catalytic roles in the research field. In terms of international cooperation, we observed that the United States has close collaborative relationships with several countries and regions, the closest of which is with China, followed by Canada and Europe. China’s collaboration model in this field is relatively focused, with close collaborations with the United States and less collaborations with other countries and regions (Figure 1F).

Institutional collaborations and the author co-occurrence network

Collaborations between institutions build influence and promote the development of the field. We conducted an analysis of the major institutions worldwide. Among 2,147 institutions, the top five institutions in terms of the number of publications were Chongqing Medical University, University of Toronto, Sun Yat-sen University, Sunnybrook Health Sciences Centre, and the 301 Hospital. The chord diagram shows the collaboration network among the top 30 productive institutions; the connected institutions have a cooperative relationship, and the thickness of the line indicates the intensity of the collaboration (Figure 2A). Most institutions tend to collaborate domestically, but institutions with a higher number of publications have a higher likelihood of international cooperation. For example, Chongqing Medical University, which has the highest publication output, has a cooperative relationship with The Royal Marsden Hospital and Toronto Metropolitan University.

Figure 2 Analysis of institutional and author distribution. (A) Chord diagram illustrating collaboration relationships among the top 30 institutions by publication volume. (B) Density visualization of institutions based on the number of citations. (C) Author collaboration network graph and overlay visualization. (D) Top 10 authors with the highest number of publications in the author collaboration network.

The density plot shows the distribution of citations for various institutions (Figure 2B). Usually, institutions with high publication volumes had a higher probability of being cited; however, some exceptions were observed. For example, the Churchill Hospital, published only 13 articles, but had 2,142 citations, ranking it second only to Chongqing Medical University, which had 5,068 citations. Researchers in specific areas or with particular viewpoints may be more likely to attract broad attention and citations. Additionally, research quality and impact are essential factors, such that high-quality research is more likely to be cited.

We also used VOSviewer to analyze author information in this research field. With a threshold condition that each author had to have published at least five articles, we reduced the initial 11,665 authors to 109 to establish an author collaboration network, removing nodes that were not present in the main network. In the collaboration network, the major research groups included Ping Liang’s team from 301 Hospital, Feng Wu, Zhibiao Wang, and Zhigang Wang’s team from Chongqing Medical University, Chris J. Diederich’s team from the University of California San Francisco, and Gregory J. Czarnota’s team from the Sunnybrook Health Sciences Centre. In terms of the timeline, Feng Wu, Chris J. Diederich, and others were among the earliest to engage in research in this field, followed by Ping Liang and others. More recently, active contributors to this field include Rongqin Zheng from Sun Yat-sen University, and Suhui Sun from Peking University (Figure 2C).

In the author collaboration network, the top five authors with the highest publication volume were Gregory J. Czarnota (n=38), Ping Liang (n=34), Jie Yu (n=29), Xiaoling Yu (n=31), and Zhibiao Wang (n=27) (Figure 2D). However, to account for the possibility that some influential researchers might not have been included in the main network due to limited collaborations, we also analyzed the total number of citations for all authors to assess their impact. Among the top five authors with the highest total citations, four were from Chongqing Medical University: Feng Wu (n=3,057), Zhibiao Wang (n=2,643), Weizhi Chen (n=2,305), Hui Zhu (n=1,672), and James E. Kennedy from Churchill Hospital (n=1,942) (Table 1).

Analysis of journals and highly cited publications

We summarized the research in this field and identified the top 15 most productive journals (Figure 3A). “Journal of Urology” and “Ultrasound in Medicine and Biology” were among the most important journals in the field of tumor treatment under interventional ultrasound. These two journals have provided a wealth of publications related to tumor treatment under interventional ultrasound, and the richness of literature resources is crucial for advancing scientific development in the field. These two journals also exhibit high h-index and g-index values (Table 2), emphasizing their significant impact and citation value in the academic field, which promotes research and innovation in this field.

Figure 3 Analysis of high-impact journals and highly cited publications. (A) The top 15 academic journals based on the number of publications and their impact factors. (B) The top 15 most frequently cited publications. (C) Dual-map overlay of the journals.

Additionally, we analyzed the most cited research articles in this field (Figure 3B and Table 3). The high citation numbers of these articles indicate their significant impact in the field and their sustained relevance over time. Most highly cited articles were typically published many years ago, but some articles rapidly accumulated citations within a decade. Notably, an article titled “High-intensity focused ultrasound in the treatment of solid tumours”, authored by James E. Kennedy in 2005, has accumulated nearly 1,000 citations (43). This article provides a comprehensive overview of HIFU technology, delving into its principles, applications, advantages, and limitations. It offers insights into the future directions of HIFU, including improvements in device design, real-time imaging, treatment monitoring techniques, and research on immune activation mechanisms. As a result, it provides a crucial reference framework for the field and has become one of the most cited articles in the field.

We also created a dual-map overlay of journals to clarify the relevance of different types of journals in this field (Figure 3C). The scatterplots on the left side of the figure represent citing journals, while those on the right side represent cited journals; colors represent the disciplines of journal sources; paths represent citation relationships; and the thickness of the link indicates the closeness of journal research content. The figure displays three paths between citing and cited journals.

The distribution and evolution of research hotspots

VOSviewer was used to create a keyword network map. Based on threshold requirement that each keyword should appear at least 18 times, a total of 3,109 keywords were extracted from the 2,588 articles. This resulted in 40 keywords used as nodes to build the network. Simultaneously, we conducted a cluster analysis of all keywords in CiteSpace software and generated topic labels for each category. In the keyword network, “ultrasound” was the keyword with the highest weight, appearing 310 times and having a total link strength of 362. This indicates its significant importance in the literature, making it a core keyword in the research. Additionally, keywords such as “hepatocellular carcinoma”, “prostate cancer”, and “high-intensity focused ultrasound” also had high link strengths, signifying that they are major topics in this research field (Figure 4A). Further, we categorized all keywords into the following 10 different categories, each with a specific research direction or focus: SDT, hepatocellular carcinoma, prostate cancer, surgery, neoadjuvant chemotherapy, ultrasound imaging, CEUS, pancreatic cancer, fusion imaging, and thermal ablation. Each category’s topic labels represent distinct research directions or focal points, helping us gain a clearer understanding of the development trends and important themes in the related research field (Figure 4B).

Figure 4 Keywords and evolutions in this research field. (A) Co-occurrence network of keywords. (B) Clustering of keywords. (C) Keyword burst analysis results from 1994 to 2023. (D) Timeline view of keywords from 1994 to 2023. CT, computed tomography.

Using the CiteSpace tool, we presented the most significant bursts among the top 25 keywords. A “burst” refers to a rapid increase in the frequency of a specific keyword in a short period. Keyword burst analysis allows us to gain insights into how the frontier hotspots in a particular field evolve, and it provides some clues about future development directions. The results showed that the early development in this research field primarily focused on exploring different types of tumor treatments. Taking liver cancer as an example, in the 1990s, Rossi and colleagues proposed ultrasound-guided RFA for the treatment of small hepatocellular carcinoma (44). The world’s first specifically constructed HIFU device was established by Peter Morris in 2002. During this period, Feng Wu and colleagues emerged as clinical pioneers of HIFU, conducting liver disease treatments. The Chongqing Haifu system, which they helped to develop, received regulatory approval for liver applications in China (45).

Consistent with the trend in research hotspots, our results indicated that HIFU became a focal point from 2004 to 2014. Since 2018, emerging technologies represented by SDT and nanoparticles have garnered attention in this field. These technologies not only provide new treatment strategies for tumors but also contribute to the immunotherapy of tumors. Research by Zhang and colleagues confirmed that the combination of nanoparticle sonosensitizers with SDT and programmed death-ligand 1 blockade induces cell ferroptosis, enhancing the therapeutic efficacy against liver cancer (31). Additionally, we noted that “safety” has become a hot topic of concern since 2019 and continues to be relevant (Figure 4C).

The timeline chart shows the changes in research keywords over time, revealing the evolution of the research field. Circles represent keywords and their first appearance over time, and lines represent connections between keywords. Similarly, we found that over time, the focus of research appears to have shifted. Initially, there was an emphasis on clinical applications in various tumors, but the improvement and enhancement of the technology itself is now being prioritized, with an increased emphasis on safety (Figure 4D).

Discussion

In general, tumor treatment under interventional ultrasound refers to tumor ablation guided by ultrasound imaging, or ablation based on high-intensity and highly focused sound waves. In this study, we conducted a comprehensive analysis of academic publications in tumor treatment under interventional ultrasound from 1960 to 2023. China and the United States, two large countries with high cancer populations, have been the most active contributors in this field with 646 and 358 publications, respectively. These two countries play a crucial role in this field, with the closest cooperative relationship, which is attributed to the scale of the cancer population in China and the United States. It is important to note that research funding, research infrastructure, and scientific talent also have a significant impact on research.

Further, there are some differences in the healthcare sector between China and the United States. Currently, China has higher cancer mortality rates for many types of cancer than the United States. According to a study in 2021 of the 10 million cancer-related deaths globally (4), China accounted for 3 million, significantly exceeding the 610,000 in the United States. The age-standardized mortality rate for cancer in China was 129.4 per 100,000 people, which was 1.5 times higher than that in the United States, where it was 86.3 per 100,000 people. Cancer mortality in the United States has been steadily declining, with a 31% reduction in overall mortality from its peak in 1991 to 2018 (4,46).

International collaborations contribute to significant breakthroughs in cancer research. Our analysis of institutional and author collaborations highlighted some closely-knit relationships. Prominent researchers and research teams, such as Ping Liang’s team at the 301 Hospital, Feng Wu, Zhibiao Wang, and Zhigang Wang’s teams at Chongqing Medical University, Chris J. Diederich’s team at the University of California San Francisco, and Gregory J. Czarnota’s team at the Sunnybrook Health Sciences Centre, have played pivotal roles in advancing the field. Finally, our keyword burst and timeline analyses showed that the research focus has gradually shifted from the exploration of clinical applications to the study of technological advancements and safety. This provides valuable insights into the trends in this field.

Currently, interventional methods are being used to treat various primary and secondary malignant tumors, offering an efficient alternative for patients with higher surgical risks. This treatment strategy can also be combined with surgery and other therapeutic approaches (47). Ultrasound imaging is a non-invasive imaging technique that provides high spatiotemporal resolution and excellent tissue penetration, making it an important tool for image guidance and ablation (48,49). The analysis of publication trends over the past 63 years in this field showed that this area has gone through different developmental stages. It started with sporadic research in the early stage (1960–2000), followed by a period of stable growth (2001–2015), and then entered a phase of rapid expansion (2016–present). As early as 1960, Dmitrieva used electron microscopy to observe early changes in Brown-Pearce tumor cells after treatment with high-intensity ultrasound. Research during the early period had a slower growth rate, and most of it was limited to the laboratory; however, these studies provided important theoretical foundations for the clinical application of this technology, and showed the effects of ultrasound therapy on tumors (50,51). From the 1990s, research that was previously confined to the laboratory and animal models began to be applied in clinical settings. In the 1990s, Sanghvi et al. (52) developed and implemented a clinical protocol for the use of focused ultrasound therapy in the treatment of benign prostatic hyperplasia. In 1991, Guthkelch et al. (53) reported on the use of focused ultrasound therapy to treat malignant brain tumors. From the 21st century, ultrasound-based tumor treatments rapidly expanded globally.

Interventional oncology offers unique local treatment strategies, including ablation (e.g., RFA, MWA, LA, and HIFU), intra-arterial chemotherapy, and embolization, which have significant advantages in terms of tumor cure, disease control, and palliative care (54). Various forms of ablation used clinically are generally considered safe; however, improper procedures can damage surrounding structures (55). Additionally, the effectiveness of tumor interventional treatments is often limited by recurrence and distant metastasis. To achieve treatment results similar to those of surgery, the ablation area is typically extended beyond the tumor boundaries; however, some clinical studies suggest that excessive ablation may lead to changes in the patient’s immune characteristics and related complications (56-58). For example, percutaneous liver tumor thermal ablation can lead to associated vascular complications (59), and ablation therapy for pancreatic diseases can induce pancreatitis (60). Additionally, several studies have examined the combination of focused ultrasound with microbubbles as a potential strategy for the disruption of the blood-brain barrier (BBB), facilitating the delivery of drugs to the brain (61,62). This approach holds great promise for drug delivery in the treatment of brain tumors. However, there are safety concerns associated with mechanical disruption of the BBB, which could lead to related neuroinflammation, and questions about its potential long-term effects remain (63). In light of these issues, current research efforts are not only seeking to make technological breakthroughs but are also increasingly emphasizing the safety of tumor treatments, which reflects the results obtained in this study.

We summarized several key directions for the future development of interventional ultrasound. First, efforts are being directed toward improving the precision of ablation techniques while simultaneously integrating various treatment modalities, including the combination with drug therapy. Second, improvements in current imaging technologies, such as new sensor technologies, signal processing algorithms, and imaging modes, can further enhance image quality and provide more accurate tumor information. With the development and application of artificial intelligence, deep-learning systems can improve image quality by pixel shift correction or by training neural networks, and this advancement will aid in the development of tumor ablation techniques guided by ultrasound or other imaging methods (64). Further, the development of nanomaterials spans multiple medical research fields (65). Nano-scale sonosensitizers or drug delivery systems can precisely target diseased tissues, which is crucial for ultrasound-based drug delivery, which in turn will minimize the impact on healthy tissues and improve treatment efficacy (66). Notably, ultrasound-based local drug delivery requires careful patient selection, as it primarily exerts a local anti-tumor effect. It is crucial that patients with genuinely localized diseases are selected for treatment (11). Physicians need to carefully evaluate each patient’s condition when formulating treatment plans to ensure the appropriateness of the treatment. Overall, through continuous research and practice, ultrasound technology is poised to transition from a conventional tumor diagnostic tool to a crucial component in tumor treatment.

This study had some limitations. It relied solely on the WoSCC database to retrieve relevant publications, which might have led to the omission of important research, as different databases may include different articles. Additionally, cancer research is a global field, and this study only included articles published in English, which might have led to the exclusion of significant studies published in other languages. Finally, variations in analytical tools, methods, and parameters might have also introduced biases into the results.

Conclusions

In this study, more than 60 years of publications and knowledge related to the field of tumor treatment under interventional ultrasound were collected and analyzed. A bibliometric analysis and data visualization analysis were conducted to examine global publication trends, institutional and author collaborations, high-productivity journals, highly cited publications, and the evolution of research hotspots in this field. With the continuous increase in the global number of publications, the research focus in this field has gradually shifted from the exploration of clinical applications to technological advancements and safety. Our findings provide valuable insights into the current developments in this field.

Acknowledgments

We would like to express our gratitude to the developers and maintainers of the database, R packages, and software used in this study.

Funding: None.

Footnote

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://qims.amegroups.com/article/view/10.21037/qims-24-1233/coif). The authors have no conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

References

1. Cortes J, Perez-García JM, Llombart-Cussac A, Curigliano G, El Saghir NS, Cardoso F, Barrios CH, Wagle S, Roman J, Harbeck N, Eniu A, Kaufman PA, Tabernero J, García-Estévez L, Schmid P, Arribas J. Enhancing global access to cancer medicines. CA Cancer J Clin 2020;70:105-24. [Crossref] [PubMed]
2. Xu Q, Zhou M, Yin P, Jin D. Projections of cancer mortality by 2025 in central China: A modeling study of global burden of disease 2019. Heliyon 2023;9:e13432. [Crossref] [PubMed]
3. Sathishkumar K, Chaturvedi M, Das P, Stephen S, Mathur P. Cancer incidence estimates for 2022 & projection for 2025: Result from National Cancer Registry Programme, India. Indian J Med Res 2022;156:598-607. [Crossref] [PubMed]
4. Wang Z, Zhou C, Feng X, Mo M, Shen J, Zheng Y. Comparison of cancer incidence and mortality between China and the United States. Precis Cancer Med 2021;4:31.
5. Rulten SL, Grose RP, Gatz SA, Jones JL, Cameron AJM. The Future of Precision Oncology. Int J Mol Sci 2023;24:12613. [Crossref] [PubMed]
6. Wang K, Wang X, Pan Q, Zhao B. Liquid biopsy techniques and pancreatic cancer: diagnosis, monitoring, and evaluation. Mol Cancer 2023;22:167. [Crossref] [PubMed]
7. Chen X, Zeh HJ, Kang R, Kroemer G, Tang D. Cell death in pancreatic cancer: from pathogenesis to therapy. Nat Rev Gastroenterol Hepatol 2021;18:804-23. [Crossref] [PubMed]
8. Liu Y, Liang W, Chang Y, He Z, Wu M, Zheng H, et al. CEP192 is a novel prognostic marker and correlates with the immune microenvironment in hepatocellular carcinoma. Front Immunol 2022;13:950884. [Crossref] [PubMed]
9. Wang K, Zhao B, Liang Y, Ma B. Identification and Validation of a Novel 2-LncRNAs Signature Associated with m6A Regulation in Colorectal Cancer. J Cancer 2022;13:21-33. [Crossref] [PubMed]
10. Wang Z, Wang K, Yu X, Chen M, Du Y. Comprehensive analysis of expression signature and immune microenvironment signature of biomarker Endothelin Receptor Type A in stomach adenocarcinoma. J Cancer 2022;13:2086-104. [Crossref] [PubMed]
11. Lakhtakia S, Seo DW. Endoscopic ultrasonography-guided tumor ablation. Dig Endosc 2017;29:486-94. [Crossref] [PubMed]
12. Schmitz AC, Gianfelice D, Daniel BL, Mali WP, van den Bosch MA. Image-guided focused ultrasound ablation of breast cancer: current status, challenges, and future directions. Eur Radiol 2008;18:1431-41. [Crossref] [PubMed]
13. Shen H, Wang L, Zhang Y, Huang G, Liu B. Knowledge mapping of image-guided tumor ablation and immunity: A bibliometric analysis. Front Immunol 2023;14:1073681. [Crossref] [PubMed]
14. Du K, Liu Y, Wu K, Sun Z, Han X, Jiao D. Percutaneous microwave ablation for lung tumors: a retrospective case-control study of conventional CT and C-arm CT guidance. Quant Imaging Med Surg 2023;13:5737-47. [Crossref] [PubMed]
15. Chen Y, Yu Q, Xu Y, Qian G, Zheng Y, Jiang L, Hu B. Ultrasound-guided peripheral nerve blockade in high-intensity focused ultrasound ablation for extra-abdominal desmoid tumors: a case series. Quant Imaging Med Surg 2024;14:1225-33. [Crossref] [PubMed]
16. Goldberg SN, Grassi CJ, Cardella JF, Charboneau JW, Dodd GD 3rd, Dupuy DE, Gervais D, Gillams AR, Kane RA, Lee FT Jr, Livraghi T, McGahan J, Phillips DA, Rhim H, Silverman SG. Image-guided tumor ablation: standardization of terminology and reporting criteria. Radiology 2005;235:728-39. [Crossref] [PubMed]
17. Zhou Y, Xu ZF, Xing W, Liu Y, Xu Z, Tan GL, Wang SR, Xu D. Comparative study of ultrasound-guided microwave ablation and traditional surgery in the treatment of plasma cell mastitis: a multicenter study. Quant Imaging Med Surg 2023;13:1838-48. [Crossref] [PubMed]
18. Goldberg SN, Gazelle GS, Mueller PR. Thermal ablation therapy for focal malignancy: a unified approach to underlying principles, techniques, and diagnostic imaging guidance. AJR Am J Roentgenol 2000;174:323-31. [Crossref] [PubMed]
19. Cao B, Liu M, Wang L, Zhu K, Cai M, Chen X, et al. Remodelling of tumour microenvironment by microwave ablation potentiates immunotherapy of AXL-specific CAR T cells against non-small cell lung cancer. Nat Commun 2022;13:6203. [Crossref] [PubMed]
20. Mansur A, Garg T, Shrigiriwar A, Etezadi V, Georgiades C, Habibollahi P, Huber TC, Camacho JC, Nour SG, Sag AA, Prologo JD, Nezami N. Image-Guided Percutaneous Ablation for Primary and Metastatic Tumors. Diagnostics (Basel) 2022.
21. Wray CJ, O'Brien B, Cen P, Rowe JH, Faraoni EY, Bailey JM, Rubin E, Tammisetti VS, Thosani N. EUS-guided radiofrequency ablation for pancreatic adenocarcinoma. Gastrointest Endosc 2024;100:759-66. [Crossref] [PubMed]
22. Camus M, Karsenti D, Levy J, Moreno M, Coron E, Esch A, Williet N, Wangermez M, Koch S, Valats JC, Pioche M, Becq A, Vanbiervliet G, Audureau E, Huguet F, Chaput U. Success rate of fiducial marker placement for treatment of esophageal or rectal cancers: a prospective multicenter study (FIDECHO study) (with video). Gastrointest Endosc 2024; Epub ahead of print. [Crossref]
23. Lesmana CRA, Paramitha MS, Gani RA. The Role of Interventional Endoscopic Ultrasound in Liver Diseases: What Have We Learnt? Can J Gastroenterol Hepatol 2021;2021:9948979. [Crossref] [PubMed]
24. Gummadi S, Eisenbrey JR, Lyshchik A. Contrast-enhanced ultrasonography in interventional oncology. Abdom Radiol (NY) 2018;43:3166-75. [Crossref] [PubMed]
25. Kim JW, Shin SS, Heo SH, Hong JH, Lim HS, Seon HJ, Hur YH, Park CH, Jeong YY, Kang HK. Ultrasound-Guided Percutaneous Radiofrequency Ablation of Liver Tumors: How We Do It Safely and Completely. Korean J Radiol 2015;16:1226-39. [Crossref] [PubMed]
26. Napoli A, Alfieri G, Scipione R, Leonardi A, Fierro D, Panebianco V, De Nunzio C, Leonardo C, Catalano C. High-intensity focused ultrasound for prostate cancer. Expert Rev Med Devices 2020;17:427-33. [Crossref] [PubMed]
27. Matsumoto K, Kato H. Endoscopic ablation therapy for the pancreatic neoplasms. Dig Endosc 2023;35:430-42. [Crossref] [PubMed]
28. Shiina S, Tateishi R, Arano T, Uchino K, Enooku K, Nakagawa H, Asaoka Y, Sato T, Masuzaki R, Kondo Y, Goto T, Yoshida H, Omata M, Koike K. Radiofrequency ablation for hepatocellular carcinoma: 10-year outcome and prognostic factors. Am J Gastroenterol 2012;107:569-77; quiz 578. [Crossref] [PubMed]
29. Sangiorgio A, Oldrini LM, Candrian C, Errani C, Filardo G. Radiofrequency ablation is as safe and effective as surgical excision for spinal osteoid osteoma: a systematic review and meta-analysis. Eur Spine J 2023;32:210-20. [Crossref] [PubMed]
30. Breen DJ, Lencioni R. Image-guided ablation of primary liver and renal tumours. Nat Rev Clin Oncol 2015;12:175-86. [Crossref] [PubMed]
31. Zhang N, Zeng W, Xu Y, Li R, Wang M, Liu Y, Qu S, Ferrara KW, Dai Z. Pyroptosis Induction with Nanosonosensitizer-Augmented Sonodynamic Therapy Combined with PD-L1 Blockade Boosts Efficacy against Liver Cancer. Adv Healthc Mater 2024;13:e2302606. [Crossref] [PubMed]
32. Xiao H, Li X, Li B, Zhong Y, Qin J, Wang Y, Han S, Ren J, Shuai X. Sono-promoted drug penetration and extracellular matrix modulation potentiate sonodynamic therapy of pancreatic ductal adenocarcinoma. Acta Biomater 2023;161:265-74. [Crossref] [PubMed]
33. Li Y, Chen W, Kang Y, Zhen X, Zhou Z, Liu C, Chen S, Huang X, Liu HJ, Koo S, Kong N, Ji X, Xie T, Tao W. Nanosensitizer-mediated augmentation of sonodynamic therapy efficacy and antitumor immunity. Nat Commun 2023;14:6973. [Crossref] [PubMed]
34. Liu Y, Wang H, Ding M, Yao W, Wang K, Ullah I, Bulatov E, Yuan Y. Ultrasound-Activated PROTAC Prodrugs Overcome Immunosuppression to Actuate Efficient Deep-Tissue Sono-Immunotherapy in Orthotopic Pancreatic Tumor Mouse Models. Nano Lett 2024;24:8741-51. [Crossref] [PubMed]
35. Zhu D, Lu Y, Yang S, Hu T, Tan C, Liang R, Wang Y. PAD4 Inhibitor-Functionalized Layered Double Hydroxide Nanosheets for Synergistic Sonodynamic Therapy/Immunotherapy Of Tumor Metastasis. Adv Sci (Weinh) 2024;11:e2401064. [Crossref] [PubMed]
36. Romanelli JP, Gonçalves MCP, de Abreu Pestana LF, Soares JAH, Boschi RS, Andrade DF. Four challenges when conducting bibliometric reviews and how to deal with them. Environ Sci Pollut Res Int 2021;28:60448-58. [Crossref] [PubMed]
37. Zhang J, Zhang Y, Hu L, Huang X, Liu Y, Li J, Hu Q, Xu J, Yu H. Global Trends and Performances of Magnetic Resonance Imaging Studies on Acupuncture: A Bibliometric Analysis. Front Neurosci 2020;14:620555. [Crossref] [PubMed]
38. Chen S, Lu Q, Bai J, Deng C, Wang Y, Zhao Y. Global publications on stigma between 1998-2018: A bibliometric analysis. J Affect Disord 2020;274:363-71. [Crossref] [PubMed]
39. Milán-García J, Caparrós-Martínez JL, Rueda-López N, de Pablo Valenciano J. Climate change-induced migration: a bibliometric review. Global Health 2021;17:74. [Crossref] [PubMed]
40. Aria M, Cuccurullo C. bibliometrix: An R-tool for comprehensive science mapping analysis. Journal of Informetrics 2017;11:959-75.
41. van Eck NJ, Waltman L. Software survey: VOSviewer, a computer program for bibliometric mapping. Scientometrics 2010;84:523-38. [Crossref] [PubMed]
42. Chen C. Searching for intellectual turning points: progressive knowledge domain visualization. Proc Natl Acad Sci U S A 2004;101:5303-10. [Crossref] [PubMed]
43. Kennedy JE. High-intensity focused ultrasound in the treatment of solid tumours. Nat Rev Cancer 2005;5:321-7. [Crossref] [PubMed]
44. Rossi S, Fornari F, Buscarini L. Percutaneous ultrasound-guided radiofrequency electrocautery for the treatment of small hepatocellular carcinoma. Journal of Interventional Radiology 1993;8:97-103.
45. Aubry JF, Pauly KB, Moonen C, Haar GT, Ries M, Salomir R, et al. The road to clinical use of high-intensity focused ultrasound for liver cancer: technical and clinical consensus. J Ther Ultrasound 2013;1:13. [Crossref] [PubMed]
46. Wei W, Zeng H, Zheng R, Zhang S, An L, Chen R, Wang S, Sun K, Matsuda T, Bray F, He J. Cancer registration in China and its role in cancer prevention and control. Lancet Oncol 2020;21:e342-9. [Crossref] [PubMed]
47. Helmberger T. The evolution of interventional oncology in the 21st century. Br J Radiol 2020;93:20200112. [Crossref] [PubMed]
48. Sridharan B, Sharma AK, Lim HG. The Role of Ultrasound in Cancer and Cancer-Related Pain-A Bibliometric Analysis and Future Perspectives. Sensors (Basel) 2023;23:7290. [Crossref] [PubMed]
49. Son S, Kim J, Kim J, Kim B, Lee J, Kim Y, Li M, Kang H, Kim JS. Cancer therapeutics based on diverse energy sources. Chem Soc Rev 2022;51:8201-15. [Crossref] [PubMed]
50. Adams JB, Moore RG, Anderson JH, Strandberg JD, Marshall FF, Davoussi LR. High-intensity focused ultrasound ablation of rabbit kidney tumors. J Endourol 1996;10:71-5. [Crossref] [PubMed]
51. Watkin NA, Morris SB, Rivens IH, ter Haar GR. High-intensity focused ultrasound ablation of the kidney in a large animal model. J Endourol 1997;11:191-6. [Crossref] [PubMed]
52. Sanghvi NT, Fry FJ, Bihrle R, Foster RS, Phillips MH, Syrus J, Zaitsev AV, Hennige CW. Noninvasive surgery of prostate tissue by high-intensity focused ultrasound. IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control 1996;43:1099-110.
53. Guthkelch AN, Carter LP, Cassady JR, Hynynen KH, Iacono RP, Johnson PC, Obbens EA, Roemer RB, Seeger JF, Shimm DS. Treatment of malignant brain tumors with focused ultrasound hyperthermia and radiation: results of a phase I trial. J Neurooncol 1991;10:271-84. [Crossref] [PubMed]
54. Lucatelli P, Iezzi R, De Rubeis G, Goldberg SN, Bilbao JI, Sami A, Akhan O, Giuliante F, Pompili M, Tagliaferri L, Valentini V, Gasbarrini A, Colosimo C, Bezzi M, Manfredi R. Immuno-oncology and interventional oncology: a winning combination. The latest scientific evidence. Eur Rev Med Pharmacol Sci 2019;23:5343-50. [Crossref] [PubMed]
55. Mauri G, Nicosia L, Varano GM, Bonomo G, Della Vigna P, Monfardini L, Orsi F. Tips and tricks for a safe and effective image-guided percutaneous renal tumour ablation. Insights Imaging 2017;8:357-63. [Crossref] [PubMed]
56. Rangamuwa K, Leong T, Weeden C, Asselin-Labat ML, Bozinovski S, Christie M, John T, Antippa P, Irving L, Steinfort D. Thermal ablation in non-small cell lung cancer: a review of treatment modalities and the evidence for combination with immune checkpoint inhibitors. Transl Lung Cancer Res 2021;10:2842-57. [Crossref] [PubMed]
57. Posa A, Contegiacomo A, Ponziani FR, Punzi E, Mazza G, Scrofani A, Pompili M, Goldberg SN, Natale L, Gasbarrini A, Sala E, Iezzi R. Interventional Oncology and Immuno-Oncology: Current Challenges and Future Trends. Int J Mol Sci 2023;24:7344. [Crossref] [PubMed]
58. Leuchte K, Staib E, Thelen M, Gödel P, Lechner A, Zentis P, Garcia-Marquez M, Waldschmidt D, Datta RR, Wahba R, Wybranski C, Zander T, Quaas A, Drebber U, Stippel DL, Bruns C, von Bergwelt-Baildon M, Wennhold K, Schlößer HA. Microwave ablation enhances tumor-specific immune response in patients with hepatocellular carcinoma. Cancer Immunol Immunother 2021;70:893-907. [Crossref] [PubMed]
59. Tashi S, Gogna A, Leong S, Venkatanarasimha N, Chandramohan S. Vascular complications related to image-guided percutaneous thermal ablation of hepatic tumors. Diagn Interv Radiol 2023;29:318-25. [Crossref] [PubMed]
60. Armellini E, Facciorusso A, Crinò SF. Efficacy and Safety of Endoscopic Ultrasound-Guided Radiofrequency Ablation for Pancreatic Neuroendocrine Tumors: A Systematic Review and Metanalysis. Medicina (Kaunas) 2023;59:359. [Crossref] [PubMed]
61. Wang J, Li Z, Pan M, Fiaz M, Hao Y, Yan Y, Sun L, Yan F. Ultrasound-mediated blood-brain barrier opening: An effective drug delivery system for theranostics of brain diseases. Adv Drug Deliv Rev 2022;190:114539. [Crossref] [PubMed]
62. Josowitz AD, Bindra RS, Saltzman WM. Polymer nanocarriers for targeted local delivery of agents in treating brain tumors. Nanotechnology 2022;34: [Crossref] [PubMed]
63. Jung O, Thomas A, Burks SR, Dustin ML, Frank JA, Ferrer M, Stride E. Neuroinflammation associated with ultrasound-mediated permeabilization of the blood-brain barrier. Trends Neurosci 2022;45:459-70. [Crossref] [PubMed]
64. Floridi C, Cellina M, Irmici G, Bruno A, Rossini N, Borgheresi A, Agostini A, Bruno F, Arrigoni F, Arrichiello A, Candelari R, Barile A, Carrafiello G, Giovagnoni A. Precision Imaging Guidance in the Era of Precision Oncology: An Update of Imaging Tools for Interventional Procedures. J Clin Med 2022;11:4028. [Crossref] [PubMed]
65. Dong S, Li X, Pan Q, Wang K, Liu N, Yutao W, Zhang Y. Nanotechnology-based approaches for antibacterial therapy. Eur J Med Chem 2024;279:116798. [Crossref] [PubMed]
66. Bérard C, Truillet C, Larrat B, Dhermain F, Estève MA, Correard F, Novell A. Anticancer drug delivery by focused ultrasound-mediated blood-brain/tumor barrier disruption for glioma therapy: From benchside to bedside. Pharmacol Ther 2023;250:108518. [Crossref] [PubMed]