Tehran University of Medical Sciences The Research in Heart Yield and Translational Medicine (RHYTHM) 3115-7270 19 1 2024 01 31 66 69 EN Azin Alizadehasl Cardio-Oncology Research Center, Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran. Ata Firouzi Cardiovascular Intervention Research Center, Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran. Haniye Hajiali Fini Adult Echocardiography Department, Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran. Parisa Firoozbakhsh Cardio-Oncology Research Center, Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran. Negar Dokhani Cardio-Oncology Research Center, Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran. Rezvaneh Shourmeij Cardio-Oncology Research Center, Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran. 2023 04 05 2023 12 12 Cancer is the second leading cause of death worldwide, and pericardial effusion is relatively common in these patients. What constitutes the best therapeutic method for treating pericardial effusion in patients with cancer is controversial. Recent decades have witnessed the introduction of percutaneous balloon pericardiotomy, an effective and less-invasive method with lower recurrence rates than pericardiocentesis for draining pericardial effusion in patients with cancer who have a poor prognosis. We herein describe 2 patients with a history of metastatic melanoma and metastatic breast cancer, presenting with symptomatic massive pericardial effusions. The patients had experienced 2 episodes of cardiac tamponade in the preceding 4 to 5 months, treated via surgical drainage. In their current episode, they were both successfully treated via percutaneous balloon pericardiotomy, and there was no recurrence of significant pericardial effusion reported during the follow-up. https://rhythm.tums.ac.ir/index.php/jthc/article/view/1827