Nonbacterial Thrombotic Endocarditis

Lung Cancer as a Leading Cause among Paraneoplastic Non-Bacterial Thrombotic Endocarditis: A Meta-Analysis of Individual Patients' Data

Hypercoagulability is strongly associated with cancer and may result in non-bacterial thrombotic endocarditis (NBTE). The aim of our meta-analysis was to explore the demographics and characteristics of this condition in cancer. Databases were systematically searched. The outcomes were to identify the annual trend in premortem diagnosis among the entire cohort and different subgroups and to identify differences in characteristics and survival in the considered population. A total of 121 studies with 144 patients were included. The proportion of marantic endocarditis associated with lung cancer was 0.29 (95% CI, 0.21-0.37; p < 0.001), that associated with pancreatic cancer was 0.19 (95% CI, 0.13-0.27; p < 0.001), that associated with advanced cancer stage (metastasis) was 0.69 (95% CI, 0.61-0.76; p < 0.001), and that associated with adenocarcinoma was 0.65 (95% CI, 0.56-0.72; p < 0.001). Median and 6-month overall survival (OS) were 1.3 months and 32.3%, respectively, with 6-month OS of 20.8% vs. 37.0% in lung vs. other cancers, respectively (p = 0.06) and 42.9% vs. 31.1% among those who underwent intervention vs. those who did not (p = 0.07). Cases discovered in recent years had better survival (HR = 0.98 (95% CI, 0.96-0.99; p = 0.003). While cancer-associated NBTE is a rare entity, lung cancers were the most common tumor site and are frequently associated with more advanced and metastatic cancer stages. The prognosis is dismal, especially among lung cancers.

Systemic thromboembolism from a misdiagnosed non-bacterial thrombotic endocarditis in a patient with lung cancer: A case report

Thromboembolic events are frequent in patients with cancer, commonly involving the venous and pulmonary circulation. The arterial system is rarely implicated in embolism and, when involved, a cardiogenic origin should always be excluded. In the present study, a case of a patient who developed multiple embolic events concomitantly with the diagnosis of locally-advanced non-small cell lung cancer with high expression levels of programmed death-ligand 1 (PD-L1) in >50% of tumor cells is reported. A cardiac defect interpreted as a patent foramen ovale required low molecular weight heparin administration. Despite the anti-coagulant therapy, before first-line anticancer treatment with pembrolizumab immunotherapy could be administered due to high PD-L1 expression levels, a new hospitalization was required due to the onset of novel ischemic manifestation. New transthoracic and transesophageal echocardiography revealed a previously misdiagnosed vegetation of the mitral valve that caused systemic embolization. The lack of any sign of infection led to the diagnosis of a non-bacterial thrombotic endocarditis (NBTE), whose embolic sprouting gave rise to the widespread ischemic events. No active anticancer treatment was feasible due to the rapid progression of the disease. NBTE can evolve quickly, eventually preventing any chance of treatment targeting the primary cause, which in the present study was lung cancer. If NBTE can be correctly diagnosed sooner then there may be the potential for anticancer therapy that does not worsen the hypercoagulability state, thus improving cancer-associated survival.