Non-bacterial thrombotic endocarditis in ovarian cancer: A systematic review

Non-Bacterial Thrombotic Endocarditis (NBTE) is characterized by the formation of sterile vegetations on the heart valves, often due to an underlying hypercoagulable state in the setting of malignancy, inflammation, or autoimmune disease. NBTE is a rare condition with a reported incidence rate of between 0.9% and 1.6%. Among gynecologic malignancies, NBTE is predominantly observed in ovarian cancer. A comprehensive review of the literature was conducted to understand the association between NBTE and ovarian cancer.

A search of PubMed/MEDLINE was conducted from database inception to January 2024 using terms related to "Non-Bacterial Thrombotic Endocarditis" and "Ovarian Cancer." Studies were included if they involved patients diagnosed with both NBTE and ovarian cancer and excluded if they did not report confirmed NBTE and ovarian cancer. Risk of bias was assessed using Mixed Methods Analysis Testing.

The search identified 15 patients from 14 case reports, all female, with an average age of 50.6. The most common presenting diagnosis was CVA (53%). Ovarian cancer was diagnosed before NBTE 57% of the time. Most patients (67%) had stage III or IV cancer. Metastases predominantly affected lymph nodes (40%), liver (40%), and the other ovary (20%). Malignancy was treated with chemotherapy in 63% of cases. Surgical resection was performed in 40% of cases. One patient underwent radiation therapy. Mortality rate was 40% in patients treated with chemotherapy and 100% in patients not receiving chemotherapy. NBTE predominantly affected the mitral valve (52.4%), followed by the aortic valve at (33.3%), and the tricuspid valve (14.3%). 80% of patients experienced organ infarct. Infarcts predominantly affected the brain (27.0%), spleen (27.0%), lung (8.1%), and heart (8.1%). NBTE was treated with anticoagulation in 54% of cases. All-cause mortality at study publication was 75%.

NBTE is an important, and often overlooked, cause of mortality in ovarian cancer. Clinicians should maintain high clinical suspicion for NBTE in patients with ovarian cancer presenting with thromboembolic phenomena.

This review was registered with PROSPERO under the ID number: CRD42024501301.