Acknowledgements
We thank all of the patients and their families, and all of the investigators at the 14 institutions that participated in the NAPOLEON study. We would also like to thank the Fukuoka Medical Oncology Group – Kyushu Yamaguchi Total Oncology Group (FMOG–KYTOG) and the Saga Study Group of Liver Disease (SASLD) for their cooperation. We are indebted to Dr. Yasunori Kawaguchi of the Saga Medical Centre Koseikan, and Dr. Masato Uenomachiof the Hamanomachi Hospital for their assistance in the data collection or discussion. We also thank Forte Science Communications for providing medical writing support.
Authors’ contributions
1. Tsuyoshi Shirakawa, Taiga Otsuka, Norio Ureshino, Toshihiko Mizuta, and Kenji Mitsugi created the study concept.
2. Tsuyoshi Shirakawa, Taiga Otsuka, Mototsugu Shimokawa, Akitaka Makiyama, Masaru Fukahori, Norio Ureshino, Toshihiko Mizuta, and Kenji Mitsugi designed the study.
3. Tsuyoshi Shirakawa, Akitaka Makiyama, Taiga Otsuka, Yudai Shinohara, Futa Koga, Yujiro Ueda, Junichi Nakazawa, Satoshi Otsu, Azusa Komori, Shiho Arima, Masaru Fukahori, Hiroki Taguchi, Takuya Honda, Taro Shibuki, Kenta Nio, Yasushi Ide, Norio Ureshino, Toshihiko Mizuta, and Kenji Mitsugi acquired the clinical data.
4. Tsuyoshi Shirakawa, Mototsugu Shimokawa, Taiga Otsuka, and Kenji Mitsugi were involved in the quality control of the data and algorithms.
5. Tsuyoshi Shirakawa, Taiga Otsuka, Mototsugu Shimokawa, Akitaka Makiyama, Toshihiko Mizuta, Kenji Mitsugi, and Eishi Baba were involved in the data analysis and interpretation.
6. Tsuyoshi Shirakawa, Taiga Otsuka, Mototsugu Shimokawa, Kenji Mitsugi, and Eishi Baba performed statistical analysis.
7. Tsuyoshi Shirakawa prepared the manuscript, and it was edited by Tsuyoshi Shirakawa, Taiga Otsuka, Mototsugu Shimokawa, Toshihiko Mizuta, Kenji Mitsugi, and Eishi Baba.
8. The manuscript was critically reviewed by all authors, and they approved the final version.
Data availability
All data generated or analyzed in this study are stored in a secured research database. Although they are not publicly available, they are available through the corresponding author upon reasonable request.
Additional information
Competing interests
M.S. received a personal fee from Sysmex Corporation; S.A. received personal fees from Taiho Pharmaceutical, Novartis Pharma, Chugai, Bristol-Myers Squibb, Daiichi-Sankyo, and AstraZeneca; A.M. received personal fees from Eli Lilly, Taiho Pharmaceutical, Ono Pharmaceutical, Bristol-Myers Squibb and Daiichi-Sankyo. The remaining authors have no competing interests or financial disclosures to declare.
Funding
This study did not receive any funding.
Ethics approval and Consent to participate
This study was conducted in accordance with the ethical guideline of the Declaration of Helsinki and was centrally approved by the Institutional review board of Saga Medical Center Koseikan (study ID 17-09-01-02), and also approved by the Institutional Review Boards or Ethics Committee of following institutions: Imari Arita Kyoritsu Hospital, Japanese Red Cross Kumamoto Hospital, Kagoshima City Hospital, Oita University Hospital, Kagoshima University Hospital, Kurume University Hospital, Japan Community Healthcare Organization Kyushu Hospital, Saiseikai Sendai Hospital, Nagasaki University Hospital, Hamanomachi Hospital, Sasebo Kyosai Hospital, Karatsu Red Cross Hospital and Fukuoka Wajiro Hospital prior to the study. Because this study was a retrospective observational study carried out in Japan, informed consent was obtained using the opt-in/opt-out approach according to each participating institution’s policy.
Consent for publication
The requirement for consent for publication was waived because of the retrospective design of this study.
Code availability
We used R ver. 4.2.0 (R Foundation for Statistical Computing, Vienna, Austria) for statistical analyses.