gms | German Medical Science

Background: Bibliometrics is the quantitative analysis of published works to map scientific activity by identifying connections between authors, research organizations, and topics. In horizon scanning, it helps assess the research landscape of a field or technology. This study aimed to provide national stakeholders with insights into the preclinical landscape of PET radiopharmaceutical research, new radioisotopes, and potential clinical applications. Using VOSViewer, a software tool developed by Leiden University, we visualized similarities between published works based on term co-occurrence and keyword frequency.

Methods: We searched Embase (Ovid) for preclinical studies published between 2020–2023, focusing on research activity prior to human trials. The search, conducted on August 29, 2023, yielded 2,620 records. These were categorized by radioisotope (e.g., F-18, 13-N, 68-Ga), with varying record counts for each. Network visualizations were created for F-18, Ga-68, Cu, and Zr, while lesser-used isotopes like 13-N, 15-O, 82-Rb, and Sc were excluded due to insufficient data. A density map analysis was also used to identify emerging research areas in records without specific isotope names in the title.

Results: Our analysis revealed that clinical research radioisotopes such as F-18, Ga-68, and Cu-64 also dominate at the preclinical stage. Few records were found for lesser-used radioisotopes (13-N, 15-O, 82-Rb, Sc), likely due to the complexity and cost of production, as well as the short shelf life of certain isotopes. The density map identified emerging research areas, including terms related to cancers (e.g., “multiple myeloma”, “glioblastoma”), non-cancer conditions (e.g., “ischemia”, “heart infarction”, “Alzheimer disease”), as well as pharmacokinetics, radiopharmaceutical research, and tissue distribution studies.

Conclusions: The visualization of similarities technique provides a quick overview of the research landscape for preclinical radionuclide studies, helping identify early research applications. While it does not replace a systematic literature review, it offers valuable leads for further investigation. Specialist knowledge is essential for accurate interpretation, and collaboration with experts is recommended for producing actionable intelligence from the results.