Five-decade bibliometric map shows sustained growth in breast cancer and frailty research

A bibliometric analysis of breast cancer and frailty research found sustained growth in publication output over five decades, reaching 115 papers in 2025, while highlighting an expanding focus on geriatric assessment, treatment tolerability, cognitive and functional outcomes, quality of life, comorbidity, and survivorship. The study synthesized 1,003 unique publications retrieved from the Web of Science Core Collection, Scopus, and PubMed for the period from 1973 through 2025, providing a quantitative map of an interdisciplinary research field concerned with vulnerability in cancer care.

The analysis, published in Frontiers in Oncology on 20 October 2026, was designed to characterize the research landscape rather than test a treatment, estimate clinical effectiveness, or assess patient outcomes. The researchers searched the three databases independently and retained English-language articles and reviews. From an initial 1,913 records, they removed 125 published after 2025 or lacking a valid publication year, excluded 13 non-target document types, and applied a three-stage deduplication process. The final library contained 1,003 papers after removal of 610 exact DOI duplicates, 153 additional duplicates identified through normalized title-and-year matching, and nine fuzzy-title matches confirmed manually. Bibliometric calculations used R, bibliometrix, VOSviewer, and CiteSpace, with citation relationships analyzed only in the eligible Web of Science subset.

Database overlap was substantial, but each source also contributed distinct coverage. Scopus supplied 759 records, Web of Science supplied 591, and PubMed supplied 422; 321 papers appeared in all three databases, while 412 final records were absent from Web of Science. This distinction matters because a database can retrieve an article when breast cancer and frailty are not both explicit in its title or abstract, for example when the concepts occur in controlled vocabulary, indexed keywords, or broader contextual discussion. A title-and-abstract audit classified 421 records, or 41.97%, as mentioning both concepts; 83 mentioned breast cancer only, 361 mentioned frailty only, and 138 mentioned neither category. The mapped corpus therefore combined direct co-mentioning publications with a broader group retrieved through indexing practices and contextual language.

Annual output remained limited before 2000, when most years produced fewer than five publications, but it rose to eight in 2000, 20 in 2010, 31 in 2014, 47 in 2018, 81 in 2021, 90 in 2023, 114 in 2024, and 115 in 2025. A segmented Poisson regression estimated an annual rate ratio of 1.133, with a 95% confidence interval of 1.119 to 1.147, before 2018 and 1.151, with a 95% confidence interval of 1.105 to 1.200, after 2018. The change in slope was not statistically significant, with a P value of 0.465. The measured pattern therefore supports sustained growth over time, but not a statistically established acceleration beginning in 2018.

The United States contributed the most publications, with 355, followed by Italy with 144 and the United Kingdom with 140. France produced 82, the Netherlands 66, Canada 61, Belgium and China 57 each, Germany 54, and Spain 41. Among these leading contributors, the highest descriptive proportions of internationally coauthored papers came from Germany at 68.5% and Belgium at 66.7%, whereas the United States had the largest output but a multiple-country publication proportion of 24.5%. Because internationally coauthored papers contribute to each participating country’s total, and because the analysis did not conduct pairwise significance tests, these percentages characterize collaboration patterns rather than establishing that one country collaborates more effectively than another.

Research activity was concentrated among established academic and clinical networks. The University of Toronto ranked first among institutions with 79 publications, followed by KU Leuven with 73, UNICANCER with 65, Harvard University with 61, and Harvard Medical Affiliates with 54. The Journal of Geriatric Oncology was the most productive journal, containing 78 mapped papers, ahead of Cancers with 36. H Wildiers was the most prolific author with 24 publications, followed by K L Cheung with 20 and H J Cohen with 19. The distribution spans oncology, geriatrics, surgery, nursing, rehabilitation, supportive care, and survivorship, indicating that breast cancer and frailty have become shared research concerns across multiple disciplines rather than remaining within a single specialty.

Keyword and network analyses identified three broad domains: identifying frailty and performing geriatric assessment; examining treatment, toxicity, mortality, and survival; and evaluating health status and patient-centered outcomes. “Breast cancer” and “frailty” were the most frequent cleaned keywords, with 852 and 539 occurrences, respectively, followed by “geriatric assessment” with 376, “quality of life” with 227, “older adults” with 200, “comorbidity” with 185, “aging” with 131, “age” with 128, and “chemotherapy” with 127. A VOSviewer network displayed 191 cleaned keywords meeting a minimum occurrence threshold of 20, but a separate Louvain analysis yielded a modularity value of 0.2560, indicating substantial overlap among its exploratory groups. The researchers therefore interpreted the colored network clusters as provisional thematic groupings rather than sharply separated or independently validated categories.

CiteSpace analyses suggested a progression from treatment-centered questions toward multidimensional assessment and longer-term consequences. In the 1995–2025 network, burst terms moved from “adjuvant chemotherapy,” “functional status,” and “comprehensive geriatric assessment” toward “clinical-trials,” “frailty,” “conserving surgery,” “older patients,” and “impact.” A more recent 2016–2025 map contained labels for radiation therapy, breast cancer survivors, HER2-negative breast cancer, geriatric assessment, aromatase inhibitors, cognitive functional outcomes, and treatment-related acute toxicity. The term “toxicity” registered a burst from 2021 through 2023, while “impact” was the only displayed long-window burst active through 2025. The recent network had modularity Q = 0.4069 and a weighted mean silhouette S = 0.7112; for 1995–2025, the corresponding values were 0.4379 and 0.7639. These algorithmic patterns describe changing attention in the literature, but they do not demonstrate that any assessment strategy or intervention improves clinical outcomes.

Citation rankings reinforced the distinction between broad visibility and thematic specificity. The citation analysis covered 591 eligible Web of Science records, or 58.9% of the integrated dataset. This subset closely matched the full collection by publication year and country, with Spearman correlations of 0.986 and 0.911, respectively, but aligned only moderately by journal, at 0.592. A 2015 systematic review on frailty in older cancer patients ranked first globally with 838 Web of Science citations, yet manual review classified it as contextual rather than directly centered on breast cancer and frailty. None of the ten most globally cited records directly examined the joint relationship as its primary question. By contrast, locally cited works more directly addressed frailty assessment, surgery in older women, treatment tolerance, cognition, quality of life, and supportive care. Citation counts therefore measured visibility within the search-defined corpus, not proof of clinical effectiveness.

The findings depict a research field gaining scale and scope, but also one with important measurement limitations. Only English-language articles and reviews were eligible, database indexing practices differed, and comparable citation analysis was unavailable across all three databases. Frailty definitions and assessment instruments vary among studies, while residual keyword variants, including “neoplasm” and “neoplasms,” may have divided some term frequencies. Network structures, cluster assignments, and bursts depend on preprocessing rules, thresholds, and software settings, and the most highly cited papers were not necessarily the most clinically focused. The bibliometric evidence demonstrates the reach and sustained momentum of the literature, but publication growth does not by itself establish improved methodological quality or clinical applicability. The authors consequently identify standardized frailty terminology and assessment, prospective intervention research, clearer links between assessment and clinical decisions, and broader participation from underrepresented regions as priorities for subsequent work.

Subject of Research: Bibliometric mapping of global breast cancer and frailty research from 1973 to 2025

Article Title: Global trends and thematic evolution in breast cancer and frailty research: a multi-database bibliometric analysis, 1973–2025

Article References: Xiang, S., Han, X., & Wang, X. (2026). Global trends and thematic evolution in breast cancer and frailty research: a multi-database bibliometric analysis, 1973–2025. Frontiers in Oncology, 16, Article 1975523. https://doi.org/10.3389/fonc.2026.1975523

Image Credits: AI Generated

DOI: 10.3389/fonc.2026.1975523

Keywords: breast cancer, frailty, geriatric assessment, geriatric oncology, bibliometrics, publication trends, treatment tolerability, survivorship, international collaboration, citation analysis, Global, trends