Bibliometric analysis of global research on PD-1 and PD-L1 in the field of cancer

Objectives To identify the cooperation of authors, countries, and institutions and explore the hot topics and future prospects regarding programmed cell death protein 1 (PD-1) and programmed cell death 1 ligand 1 (PD-L1) research. Materials and methods Publications on PD-1 and PD-L1 research were retrieved from the Web of Science Core Collection. Bibliometric analyses were performed using VOSviewer 1.6.9, HistCite 2.1, and CiteSpace V software. Network maps were generated to evaluate the collaborations between different authors, countries, and institutions. Results A total of 7359 articles related to PD-1 and PD-L1 research in the field of cancer were identified. We observed rapid growth in the number of publications since 2014. Oncoimmunology (326, 4.43%) had the highest number of publications, while N Engl J Med (18,828 co-citations, 6.30%) was the most co-cited journal. Hodi FS and Wolchok JD were key researchers. There were active collaborations among the top authors. The USA was the leading contributor in this field with 3496 publications. Active cooperations between countries and between institutions were observed. The main hot topics included matters related to the efficacy and prognosis of various tumors after treatment with PD-1 and/or PD-L1 inhibitors, as well as the activation or expression of important immunological factors targeted at tumors. Conclusion PD-1 and PD-L1 studies have significantly increased after 2014. The USA contributed the most publications. There were active cooperations between authors, countries, and institutions. Further research should expand and develop new topics such as those likely to boost therapeutic strategies for cancer.