Primary mediastinal large-B-cell lymphoma: radiologic findings at presentation

Primary mediastinal large-B-cell lymphoma was recently reclassified as a distinct clinical entity. We wished to review the imaging findings for this disease and to compare the findings with those for other disorders with a similar appearance.

We retrospectively reviewed plain films, gallium scintigrams, MR images, and CT scans for 43 patients with primary mediastinal large-B-cell lymphoma.

All but one lesion arose in the anterior mediastinum. Areas of fluid attenuation within the masses were evident on CT scans in 50% of cases. Pleural effusions were seen by chest radiography in 33% of patients. Pericardial effusions were present in 32% of patients who underwent CT scans. Of the 21 patients who underwent gallium scintigraphy, all were reported to have positive findings. Also, MR imaging showed evidence of superior vena cava syndrome in one patient.

Primary mediastinal large-B-cell lymphoma typically is seen as a bulky anterior mediastinal mass that often contains areas of necrosis.