The prevalence of neoplastic pericardial diseases has changed over time and varies according to diagnostic methods. The diagnostic factor is usually the detection of neoplastic cells within the pericardial fluid or in specimens of pericardium, but the diagnosis may be difficult. Accurate sampling and cytopreparatory techniques, together with ancillary studies, including immunohistochemical tests and neoplastic marker dosage, are essential to obtain a reliable diagnosis. The goals of treatment may be simply to relieve symptoms (cardiac tamponade or dyspnea), to prevent recurrent effusion for a long-term symptomatic benefit, or to treat the local neoplastic disease with the aim of prolonging survival. Immediate relief of symptoms may be obtained with percutaneous drainage or with a surgical approach. For long term prevention of recurrences, various approaches have been proposed: extended drainage, pericardial window (surgical or percutaneous balloon pericardiostomy), sclerosing local therapy, local and/or systemic chemotherapy or radiation therapy (RT) (external or with intrapericardial radionuclides). The outcomes of various therapeutic approaches vary for different tumor types. Lymphoma and leukemias can be successfully treated with systemic chemotherapy; for solid tumors, percutaneous drainage and the use of systemic and/or localsclerosing and antineoplastic therapy seems to offer the best chance of success. The use of “pure” sclerosing agents has been replaced by agents with both sclerosing and antineoplastic activity (bleomycin or thiotepa), which seems to be quite effective in breast cancer, at least when associated with systemic chemotherapy. Local chemotherapy with platinum, mitoxantrone and other agents may lead to good local control of the disease, but the addition of systemic chemotherapy is probably relevant in order to prolong survival. The surgical approach (creation of a pericardial window, even with the mini-invasive method of balloon pericardiostomy) and RT may be useful in recurring effusions or in cases that are refractory to other therapeutic approaches. The prevalence of neoplastic pericardial diseases has changed over time and variation according to diagnostic methods. The diagnostic factor is usually the detection of neoplastic cells within the pericardial fluid or in specimens of pericardium, but the diagnosis may be difficult. Accurate sampling and cytopreparative techniques, together with ancillary studies, including immunohistochemical tests and neoplastic marker dosage, are essential to obtain reliable diagnosis. The goals of treatment may be simply to relieve symptoms (cardiac tamponade or dyspnea), to prevent recurrent effusion for a long-term symptomatic benefit, or to treat the local neoplastic disease with the aim of prolonging survival. Immediate relief of symptoms may be obtained with percutaneous drainage or with a surgical approach. For long term prevention of recurrences, various approaches have been proposed: extended drainage, pericardial window (surgical or percutaneous balloon pericardiostomy), sclerosing local the rapy, local and / or systemic chemotherapy or radiation therapy (RT) (external or with intrapericardial radionuclides). The outcomes of various therapeutic approaches vary for different tumor types. Lymphoma and leukemias can be successfully treated with systemic chemotherapy; for solid tumors, percutaneous drainage and the use of systemic and / or localsclerosing and antineoplastic therapy seems to offer the best chance of success. The use of “pure ” sclerosing agents has been replaced by agents with both sclerosing and antineoplastic activity (bleomycin or thiotepa), which seems to be quite effective in breast cancer, at least when associated with systemic chemotherapy. Local chemotherapy with platinum, mitoxantrone and other agents may lead to good local control of the disease, but the addition of systemic chemotherapy is likely relevant in order to prolong survival The surgical approach (creation of a pericardial window, even with the mini-invasive method of balloon pericardiostomy) and RT may be useful in recurring effusions or in cases that are refractory to other therapeutic approaches.