AUTHOR=Kushnareva Ekaterina , Stepanova Maria , Artemeva Elizaveta , Shuginova Tatyana , Kushnarev Vladimir , Simakova Maria , Moiseenko Fedor , Moiseeva Olga TITLE=Case Report: Multiple Causes of Cardiac Death After the First Infusion of Atezolizumab: Histopathological and Immunohistochemical Findings JOURNAL=Frontiers in Immunology VOLUME=13 YEAR=2022 URL=https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2022.871542 DOI=10.3389/fimmu.2022.871542 ISSN=1664-3224 ABSTRACT=

Immune checkpoint inhibitors are promising agents for anticancer therapy. But despite their high efficacy in the treatment of solid tumors, there is still a problem with immune-related adverse events, especially cardiovascular complications with a very high mortality rate. Myocarditis or ischemic heart disease progression is not the only possible cause of cardiovascular death in patients treated with checkpoint inhibitors. We report a case of a patient with mucinous carcinoma of the lung, with a previous history of hypertension and moderate left ventricular dysfunction. The patient was prescribed atezolizumab, but the first atezolizumab infusion resulted in the patient cardiovascular death. Postmortem histopathological evaluation of myocardium revealed several possible reasons for hemodynamic instability: tumor embolism of the coronary arteries, micrometastases of mucinous carcinoma in the myocardium, and myocarditis diagnosed by both Dallas and immunohistochemistry criteria. In addition, testing for expression of PD-L1 detected the high levels of membranous and cytoplasmic PD-L1 protein even in the myocardium area free from tumor cells. The present clinical case demonstrates a problem of cardiovascular death in patients treated with checkpoint inhibitors and actualizes the need for future research of potential risk factors for cardiovascular complications.