Massive Pericardial Effusion Revealing Ovarian Cancer in a 36-Year-Old Woman: A Case Report

Background Pericardial effusion is a clinical entity with multiple etiologies, of which malignancy accounts for 5–10% of cases. Ovarian cancer rarely presents initially with pericardial involvement. Case Presentation We report the case of a 36-year-old woman with no prior medical history or cardiovascular risk factors, admitted with progressively worsening dyspnea and hemodynamic instability. Transthoracic echocardiography demonstrated a massive pericardial effusion with tamponade physiology. Emergency pericardiocentesis drained 800 mL of serohemorrhagic fluid. Cytological and imaging workup identified an ovarian mass, and histopathological confirmation was obtained following cytoreductive surgery. The patient subsequently received platinum–taxane-based adjuvant chemotherapy, resulting in clinical improvement and no recurrence of pericardial effusion during follow-up. Conclusion This case highlights the importance of considering a malignant etiology in large pericardial effusions, even in young patients without comorbidities, and underscores the role of timely multidisciplinary oncologic management in improving outcomes.