The choice therapy of malignant pericardial effusion is controversial. Pericardiocentesis is usually successful in alleviating tamponade, but unfortunately, that tamponade recurs frequently and patients are then again exposed to a critical situation and need hospitalization. Several different approaches have been advocated in order to prevent reaccumulation of the pericardial fluid, most of them quite cumbersome. We present our experience with intrapericardial administration of cisplatin. There were 6 patients, and the primary tumor was breast carcinoma in 2, lung in 1, ovary in 1, mediastinal fibrosarcoma in 1, and unknown in 1. Administration of cisplatin was virtually uneventful and painless, and there were no recurrences, with a survival of 2 to 18 months (mean 5.6).We conclude that intrapericardial cisplatin is safe and effective in treating malignant pericardial tamponade and preventing recurrence.