Diffuse Large B-Cell Lymphoma
The high-grade non-Hodgkin lymphoma is characterized by a diffuse proliferation of large neoplastic B cells, typically showing nuclear size equal to or greater than the size of a normal macrophage. It is the second most common pulmonary lymphoma after maltoma. It occurs in a wide age range from children to adults. Patients are usually symptomatic. Grossly, the lesions are nodular in configuration and show no lobar predilection. Histopathologically, the process is highly distinctive involving both the pleura and the vascular system of the lung, features that can also be observed in imaging studies of the chest. The underlying lung architecture is usually obliterated, often with necrosis. In some cases, the neoplastic lymphoma cells occupy the alveolar spaces, a pneumonic-like process that has been termed tumoral pneumonia.