Cytology positive pericardial effusion causing tamponade in patients with high grade serous carcinoma of the ovary

•Three patients with cytology positive pericardial effusions from high grade serous carcinoma.•Patients' conditions amenable to treatment with chemotherapy after effusion symptom improvement.•Patient with pericardial effusion from high grade serous ovarian cancer post a poly ADP ribose polymerase inhibitor.