A Curious Case of Pericardial Effusion Diagnosed as Diffuse Large B-cell Lymphoma

Lymphoma arises from mature B, T, and natural killer (NK) cells. Lymphomas are classified into Hodgkin's lymphoma (HL) and non-Hodgkin's lymphoma (NHL). Diffuse large B-cell lymphoma (DLBCL) is a type of NHL. It can present with symptoms such as fever, chills, or night sweats, as well as symptoms due to extranodal involvement. Extranodal sites can include the gastrointestinal tract or renal involvement. A higher risk of developing diffuse large B-cell lymphoma (DLBCL) is seen in patients with congenital or acquired immunodeficiency, those on immunosuppression, and those with autoimmune disorders. In this case report, we present a case of pericardial effusion that, upon further evaluation, was diagnosed as diffuse large B-cell lymphoma (DLBCL). A 64-year-old male presented with complaints of retrosternal chest pain that progressed from New York Heart Association (NYHA) Grade II to IV over a month. The chest pain was moderate intensity, dull aching, and non-radiating. It was associated with orthopnea, paroxysmal nocturnal dyspnea, and anasarca. A chest X-ray (posteroanterior {PA} view) showed cardiomegaly with an increased cardiothoracic ratio, mediastinal widening, and pulmonary congestion. Echocardiography revealed moderate non-tappable pericardial effusion. A high-resolution computed tomography (HRCT) chest scan showed moderate pericardial effusion and a homogeneous enhancing mass in the left anterior superior mediastinum. A computed tomography (CT)-guided biopsy was performed to check for lymphoma, thymoma, or tuberculosis. The patient was diagnosed with diffuse large B-cell lymphoma (DLBCL). Owing to the diverse manifestations of diffuse large B-cell lymphoma (DLBCL), prompt diagnosis is required for controlling disease progression.