Bibliometric analysis of global research on breast reconstruction after mastectomy for breast cancer from 2011 to 2021

Breast cancer is the most common malignant tumor in the world, and most patients require a mastectomy. Women who have undergone mastectomy often suffer from breast loss that seriously affects their daily life, and breast reconstruction is not only beneficial to patient's quick recovery after surgery, but also their mental health. So, in recent years, more and more female breast cancer patients are receiving breast reconstruction surgery. We aim to map hot trends in breast reconstruction after mastectomy for breast cancer and provide directions for future research.


| INTRODUC TI ON
Breast cancer is the most common malignant tumor in the world. 1,2 The main treatment for breast cancer is surgery, which includes the entire breast, pectoralis major, pectoralis minor, and axillary lymph nodes. 3,4 Because of the large surgical resection range and the need to remove the breast, it seriously affects the appearance of women after surgery, which is easy to bring psychological secondary trauma to female breast cancer patients. 5 Recently, with the development of the economy, more and more women pay more attention to the beauty of breasts after surgery, so they are more inclined to regain a complete breast through breast reconstruction.
Breast reconstruction includes one-stage reconstruction and two-stage reconstruction. The former performs breast reconstruction at the same time as mastectomy, so there is no psychological pain of breast loss, and the latter is delayed reconstruction after breast cancer surgery. 5,6 Breast reconstruction can not only improve the physical shape of patients after breast cancer surgery, but also restore the patient's psychological self-confidence. These are in line with the principles of modern fast recovery surgery and are beneficial to the physical and mental health of patients after surgery. 7 The many advantages of breast reconstruction have led more and more physicians to recommend postoperative breast reconstruction for breast cancer patients, which has also prompted a large number of publications in this field. However, up to now, no studies have been conducted to summarize and analyze the overall trend of relevant literature on breast reconstruction after mastectomy for breast cancer. Therefore, it is necessary to conduct a bibliometric analysis of relevant literature in this field.
Bibliometrics uses mathematical and statistical methods to quantitatively analyze the internal connections and distribution patterns between documents according to the country, institution, author, and other parameters of published documents to discover the research status, research hotspots and future trends in a certain field. Therefore, this study uses bibliometrics to conduct a quantitative and qualitative comprehensive evaluation of related research on the field of breast reconstruction after breast cancer surgery in the past 10 years, and conduct statistical analysis on the number of publications, institutions, and keywords, aiming to continuously explore hot topics and research trends in this field, providing directions for future research directions.

| Bibliometric analysis
After extracting data from WoS, we first analyzed the number of publications and citation trends for breast reconstruction after mastectomy for breast cancer and visualized them using Excel. Then, bibliometrics, breast cancer, breast plastic surgery, breast reconstruction, mastectomy F I G U R E 1 Literature search methods and screening process.
use CiteSpace V and VOSviewer to perform bibliometric analysis, including national publications, and institutional publications. Analysis methods include coupling analysis, co-citation analysis, and keyword co-occurrence. Use the latest 2021 edition of the Journal Citation Report (JCR) to get the latest Impact Factor (IF, 2021).

| Overall distribution and global contributions
A total of 3404 original articles and reviews related to breast reconstruction after mastectomy for breast cancer were screened. Since Annual trends in U.S. publications and citations have been increasing steadily from 2011 to 2021, and while U.S. publications in this field have slowed over the past 5 years, publications and citations in the U.S. are still much higher than in other countries ( Figures S1,S2). In addition, it can be seen from the inter-country cooperation network map ( Figure 2C) and the density map ( Figure 2D) that countries such as the United States, the United Kingdom, and Italy are located in the central node of the multinational cooperation network, and are closely connected with other countries. Not only is the United States at the center of the density map, but it is one of the first countries to publish in the field ( Figure 2D,E). In conclusion, the number of publications and citations related to breast reconstruction after mastectomy for breast cancer is much higher than that of other countries, and the United States is the leader in this field.

| Analysis of institutions and authors
According to an analysis of publishing institutions, a total of 2957 institutions conducted research in the field of breast reconstruction after mastectomy for breast cancer. Table 2

| Analysis of journals
A total of 503 journals accepted and published articles on breast reconstruction after mastectomy for breast cancer, and Table 4   collaboration between journals were analyzed ( Figure  Reconstructive Surgery were the earliest journals to publish in the field ( Figure 4D).

| Analysis of cited and co-cited references
The citation and co-citation analysis of the literature provides insight into the most influential research in the field and guides the basic direction of future research. The top 10 most cited publications are listed in Table 5 and the top 11 most co-cited publications are listed in

| Analysis of keywords
Keywords are a generalization of the central idea of the research, and keyword co-occurrence analysis helps to understand the internal relationship between keywords in the field of breast reconstruction after mastectomy for breast cancer. The extensive network of co-occurrence keywords was visualized by VOSviewer ( Figure 6A).
Among them, breast cancer, mastectomy, breast reconstruction, cancer, and reconstruction were the most common co-occurrence keywords and had the strongest correlation with other keywords.
Based on keyword co-occurrence network analysis, keyword classification analysis was performed, and Figure 6B shows the top 25 co-occurring keywords of the strongest citation bursts. The results showed that the keyword with the highest burst intensity was carcinoma (13.11), followed by local recurrence (7.69) and partial mastectomy defect (7.52   continues to increase, the treatment of breast cancer has gradually transitioned from a single surgical treatment to a multi-disciplinary comprehensive treatment, including breast surgery, medical oncology, and plastic surgery. 7,18 This phenomenon indicates that clinicians are increasingly concerned about the improvement of patients' psychological health, 14   found that immediate breast reconstruction in breast cancer patients increased the probability of complications such as infection and hematoma. Therefore, Matar does not recommend premature breast reconstruction for breast cancer patients. These differences indicate that different scholars in the medical community hold different views on the pros and cons of immediate breast reconstruction. However, overall breast reconstruction is physically and psychologically beneficial and worth promoting for patients. Recent studies also suggest that the choice of prophylactic contralateral mastectomy and reconstruction for patients with unilateral breast cancer is the future trend, rather than mastectomy alone. 29 In conclusion, based on the references burst analysis and keywords burst analysis in the past 10 years, it is not difficult to find that breast reconstruction after mastectomy for breast cancer is a hot topic of research by scholars, and more and more scholars recommend breast reconstruction after mastectomy for breast cancer, preventive contralateral mastectomy with breast reconstruction may be the future.
Based on the WoSCC database, this study identified the relevant literature on breast reconstruction after mastectomy for breast cancer in the past 10 years and synthesized the current hot trends.
However, this study still has some limitations. For example, we included only English-language literature, which would have resulted in the exclusion of much non-English literature. Therefore, multicenter collaboration with researchers from other countries is possible for broader and more in-depth studies.

| CON CLUS ION
In summary, this study provides a comprehensive quantitative and qualitative assessment of the published literature in the field of breast reconstruction after mastectomy for breast cancer between 2011 and 2021. In the last decade, the number of publications related to breast reconstruction after mastectomy for breast cancer has increased significantly. Breast reconstruction is beneficial for the physical and mental health of patients after surgery, and more experts increasingly recommend breast reconstruction for mastectomy patients with breast cancer.

AUTH O R CO NTR I B UTI O N S
HZ and YG performed the research. JY and YH designed the research study. RG and HJ contributed essential reagents and tools. JX analyzed the data. HZ wrote the paper.

ACK N OWLED G M ENTS
We are grateful for the good scientific research platform provided by Dongfang Hospital Affiliated to Tongji University.

CO N FLI C T O F I NTE R E S T
The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.