Rare case of primary pleural lymphoma presenting with pleural effusion

Primary pleural lymphoma is rare and has been described in association with human immunodeficiency virus (HIV) infection or pyothorax. We report a rare case of primary pleural lymphoma in a 73‐year‐old man who presented with chest pain and no history of HIV infection or pyothorax. Chest imaging showed pleural thickening and pleural effusion. Thoracoscopic pleural biopsy was performed. Histopathological and immunohistochemical examinations conformed to that of a diffuse large B‐cell lymphoma. Physicians should be aware of this rare location of primary lymphoma and implement thoracoscopy as soon as possible.