ADENOCARCINOMA OF THE LUNG PRESENTING AS AN ACUTE STROKE: THE CLINICAL CHALLENGE OF NONBACTERIAL THROMBOTIC ENDOCARDITIS

Abstract

SESSION TITLE: Medical Student/Resident Lung Cancer Posters SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: October 18-21, 2020 INTRODUCTION: Nonbacterial Thrombotic Endocarditis (NBTE) is an under recognized etiology of new heart murmurs and systemic emboli. Caused by aseptic fibrin and platelet aggregates on heart valves due to an underlying hypercoagulable state such as malignancy, NBTE carries high morbidity and mortality and is often a post-mortem diagnosis. Treatment involves systemic anticoagulation, valve repair and tailored management of the primary condition. CASE PRESENTATION: A 66-year-old man was referred to the Pulmonology clinic for evaluation of an 8cm x 6 cm right lower lobe cavitary mass with associated hilar and mediastinal lymphadenopathy, which was incidentally found during a recent hospitalization for a cerebrovascular accident. His medical history was significant for hypertension and a recent right middle cerebral artery stroke with residual left hemiparesis and scattered infarcts throughout bilateral parietal lobe and cerebellum. He reported a 35 pack-year tobacco smoking history and a 30-pound unintentional weight loss but denied respiratory symptoms. Physical exam showed left arm weakness, but was otherwise unremarkable. As part of the stroke work up, a transthoracic echocardiogram showed thickening and calcification of the aortic leaflets. NBTE was suspected in the setting of a possible lung neoplasm. A transesophageal echocardiogram was performed and showed a 0.8 cm x 0.8 cm solid vegetation at the tip of the right coronary cusp of the aortic valve. Infective endocarditis was ruled out via negative blood cultures and the absence of fever or septic features. A PET-CT scan revealed multiple hypermetabolic lesions in the lower and middle lobes of the right lung, N1, N2 lymph nodes, left adrenal gland and in the soft tissue of the right scapula. Histopathology of the scapular lesion was consistent with adenocarcinoma of the lung that was EGFR/BRAF/ALK/ROS1 negative, KRAS positive with PD-L1 50% expression. He was started on Pembrolizumab and palliative chemotherapy. Since the patient ultimately opted for hospice care, anticoagulation therapy was not initiated. DISCUSSION: Serious neurocognitive impairment and other cerebrovascular complications as the result of recurrent embolization worsen the overall prognosis of patients with NBTE. Therefore, a high index of suspicion for prompt diagnosis and treatment of the underlying cause is critical. CONCLUSIONS: Underlying malignancy must be considered in the differential diagnosis of a patient with systemic emboli, aseptic endocarditis and constitutional symptoms. Reference #1: Bussani R, De-Giorgio F, Pesel G, et al. Overview and Comparison of Infectious Endocarditis and Non-infectious Endocarditis: A Review of 814 Autoptic Cases. In Vivo. 2019;33(5):1565-1572. Reference #2: Petrescu I, Aung H, Ionescu F, et al. Nonbacterial Thrombotic Endocarditis Despite Anticoagulation with New Oral Anticoagulants. Journal of the American College of Cardiology. 2018;71(11):A2308 DISCLOSURES: No relevant relationships by Nabeel Azzawi, source=Web Response No relevant relationships by Roberto Pineda-Reyes, source=Web Response No relevant relationships by Natarajan Rajagopalan, source=Web Response No relevant relationships by Irene Riestra Guiance, source=Web Response