Purpose: Cardiac dysfunction as a result of anthracycline treatment is a major concern regarding the management of patient life after therapy. The aim of the present study was to determine the clinical characteristics of cancer patients at high risk of developing cancer therapy-related cardiac dysfunction (CTRCD), in order to improve the risk management for the appropriate treatment., Methods: This is a single-center, retrospective study of patients with breast cancer who underwent anthracycline treatment and had regular consultations with cardiologists. To investigate the incidence of CTRCD and the risk factors related to its occurrence, left ventricular ejection fraction (LVEF), cardiac troponin I (TnI), and brain natriuretic peptide (BNP) were assessed in 177 patients at the start of anthracycline treatment, and again at 3, 6, 9, and 12 months., Results: Eight patients (4.5%) developed CTRCD (CTRCD group). The comparisons between the CTRCD group and those without CTRCD (non-CTRCD group) showed significant differences in pre-treatment cancer stage and neutrophil/lymphocyte ratio (NLR). Multivariate analysis showed a strong association between pre-treatment cancer stage, NLR, and type of anthracycline administered (epirubicin or doxorubicin)., Conclusion: High NLR, the more advanced stages of cancer, and doxorubicin administration were suggested as possible risk factors for the development of CTRCD. Special attention should be warranted for patients with any of these risk factors., Competing Interests: Declarations. Ethics approval: All the procedures performed in studies involving human participants were carried out in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. For this type of study, formal consent is not required. Consent to participate: For this type of study, formal consent is not required. Consent for publication: Not applicable. Competing interests: MO, ES and YT have nothing to declare. JK has received honoraria from Chugai, Astellas, Ono Pharma, Bristol-Myers Squibb, Daiichi Sankyo, Taiho, Terumo, Eli Lill, and Nipponkayaku. ET has received honoraria from Pfizer., Sanofi, MSD, Eisai, Chugai, TAIHO, Johnson & Johnson, and AstraZeneca. KT has received grants and/or and contracted clinical trials from Chugai, Eisai, Taiho, Takeda, MSD, Daiichi Sankyo, Eli Lill, Asahi Kasei, Nipponkayaku, Kyowa Kirin, Asteras, and Maruho; honoraria from Chugai, Astra Zeneca, Pfizer, Eisai, Daiichi Sankyo, Eli Lill, Novartis, MSD, Nipponkayaku, Hisamitsu, Kyowa Kirin, Asahi Kasei, Taiho, and PDR Pharma. TO has received grants and/or contracted clinical trials from Chugai, Eisai, Taiho, Takeda, Asahi Kasei, Daiichi Sankyo, Eli Lilly, Nipponkayaku, Kyowa Kirin; honoraria from Chugai, Pfizer, Astra Zeneca, Eisai, Daiichi Sankyo, Eli Lilly, Kyowa Kirin, Novartis, FUJIFIRM Toyama Chemical, Johnson & Johnson, Asahi Kasei, Exact Sciences, Otsuka, and MSD. SS has received grants and/or contracted clinical trials from Taiho, Eisai, Chugai, Takeda, MSD, Astra Zeneca, Daiichi Sankyo, Gilead, Eli Lilly, and Sanofi; honoraria from Chugai, Kyowa Kirin, MSD, Novartis, Eisai, Takeda, Daiichi Sankyo, Eli Lilly, Astra Zeneca, Pfizer, Taiho, Ono, Nipponkayaku, Gilead, and Exact Sciences; participation on a data safety monitoring board or advisory board for Chugai/Roche, Astra Zeneca, Eli Lilly, Pfizer, Kyowa Kirin, Daiichi Sankyo, and MSD; and executive board membership of Japan Breast Cancer Research Group, Japan Breast Cancer Society, Japanese Society of Medical Oncology, and Breast International Group., (© 2024. The Author(s).)