Occipital Stroke Due to Non-bacterial Thrombotic Endocarditis as the Initial Manifestation of Endometrioid Ovarian Cancer.

Ischemic stroke is a rare initial manifestation of malignancy. We report the case of a 46-year-old female who presented with an embolic stroke, subsequently found to be due to endometrioid ovarian carcinoma. She presented to our clinic with sudden-onset bilateral visual blurring and syncope. Neurological examination was unremarkable. Investigations revealed iron-deficiency anemia and elevated C-reactive protein. Brain MRI showed multiple cardioembolic infarcts in the bilateral frontoparietal lobes and cerebellum. transesophageal echocardiogram (TEE) revealed a left atrial mass attached to the posterior mitral leaflet, suggestive of non-bacterial thrombotic endocarditis (NBTE). Further workup, with CT of the abdomen and pelvis, finally revealed a solid-cystic right ovarian mass, suggestive of a neoplasm, with right iliac lymphadenopathy and left ovarian endometriotic cysts, along with elevated cancer antigen (CA)-125 levels. The patient underwent bilateral salpingo-oophorectomy, with surgical staging confirming grade-2 endometrioid adenocarcinoma. She received chemotherapy (paclitaxel/ carboplatin) for stage 3 disease, following which she improved clinically and her cancer antigen (CA)-125 levels normalized. This report highlights stroke due to NBTE as a rare initial presentation of endometrioid ovarian carcinoma, a histologic subtype not known for hypercoagulability. It emphasizes the need to consider occult malignancy in young patients presenting with embolic stroke in the absence of conventional vascular risk factors. Clues towards occult malignancy included unexplained anemia, elevated inflammatory markers, and the "Three Territory Sign" (TTS) on MRI. Furthermore, the report adds to the literature regarding NBTE, an underrecognized entity strongly associated with cancer. A high degree of suspicion, along with a systematic approach to workup, can facilitate early diagnosis in these patients.