Primary pleural or pericardial lymphomas are rare, but 2 types of lymphoma characteristically involve the pleura and/or pericardium: 1) Primary effusion lymphomas (PEL) are usually presenting as a serious effusion in body cavities without detectable tumor masses, but must have evidence, by definition, of Kaposi’s sarcoma-associated herpes virus 8 infection (HHV-8). ¹ Complex karyotypes have been observed in a few cases so far analyzed. ² 2) Diffuse large B-cell lymphoma a mass-forming lymphoma, associated with chronic inflammation and with EBV, as known as PEL-like lymphoma or HHV8-unrelated PEL-like lymphoma, or pyothorax-associated lymphoma (PAL) in the pleural cavity. An unusually high frequency of TP53 mutations was detected in the PAL specimens; ³ MYC amplification;⁴ distinct gene expression profile from that of nodal DLBCL, with an increased expression of IFI27. ⁵ Other types of lymphoma may also exceptionally occur.