Ovarian Endometrioid Carcinoma Presenting With Presumed Right Ventricular Intracardiac Metastasis and Superimposed Thrombus: A Rare Manifestation of Gynecologic Malignancy

Cardiac metastases are uncommon clinically, and intracavitary right ventricular involvement from gynecologic malignancies is exceedingly rare. We report a 69-year-old woman with multiple cardiovascular comorbidities and a recently diagnosed FIGO (International Federation of Gynecology and Obstetrics) grade 3 endometrioid carcinoma after having an exploratory laparotomy for a pelvic mass, resulting in total hysterectomy and bilateral salpingo-oophorectomy, with findings consistent with an ovarian mass and biopsy results showing endometrioid carcinoma. She was referred to the hospital after routine oncologic imaging raised concern for a right ventricular mass with associated thrombus. This patient had no symptoms on initial presentation and underwent further evaluation in the inpatient setting. Cardiac magnetic resonance imaging demonstrated a right ventricular structure extending into the right ventricular outflow tract with suspected enhancement at the attachment site to the interventricular septum, concerning for intracardiac metastatic disease with superimposed thrombus. Computed tomography of the chest demonstrated innumerable pulmonary nodules, concerning for hematogenous dissemination. Given prohibitive operative risk, surgical resection was deferred, and this was treated as presumed intracardiac metastasis with superficial thrombus. The patient was started on Warfarin for anticoagulation due to the cost-prohibitive effects of DOAC (direct oral anticoagulant) for the thrombotic component and discharged with oncology follow-up. This case highlights an exceptionally rare pattern of gynecologic malignancy involving the right ventricle, with diagnostic and therapeutic challenges related to distinguishing tumor from thrombus and balancing embolic risk against surgical morbidity.