Diffuse myocardial infiltration in secondary cardiac lymphoma: A case report

Cardiac lymphomas are rare, with a high proportion developing as secondary lymphomas. The symptoms of secondary heart lymphoma are often nonspecific and may not be detected promptly, leading to a poor prognosis. This case report describes the case of a 53-year-old male patient diagnosed with diffuse large B-cell lymphoma originating in the thymus. Prior to treatment, ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) confirmed the diagnosis of diffuse lymphoma invasion in the heart. After chemotherapy, the cardiac lesions largely regressed. Cardiac magnetic resonance imaging, echocardiography and PET/CT revealed post-chemotherapy tumor necrosis and fibrosis in the myocardium, resulting in the formation of a left ventricular aneurysm. This case report discusses the diagnosis and treatment of secondary cardiac lymphoma, focusing on diffuse myocardial infiltration as the primary manifestation.