A 58-year-old male initially presented to the hospital with deep vein thrombosis, pulmonary embolism and cerebral infarctions ultimately leading to diagnosis of metastatic epidermal growth factor receptor (EGFR) positive lung cancer, likely in the setting of marantic endocarditis. He was then treated under the FLAURA-2 trial and received chemotherapy (cisplatin and pemetrexed) plus Osimertinib. The patient did initially sustain clinical and radiographic response with treatment. However, he later developed recurrent cerebrovascular events, which temporally coincided with progression of the patient’s lung cancer. This subsequently led to the diagnosis of non-bacterial thrombotic (NBTE) or marantic endocarditis pertaining to not only initial diagnosis of patient’s EGFR mutated pulmonary malignancy, but also correlated with progression of disease.

Keywords: EGFR-positive Lung Cancer; Non-bacterial thrombotic endocarditis; Marantic endocarditis; Malignancy