An 84-year-old woman presented to our hospital with dyspnea on exertion and left back pain. Chest X-ray and chest computed tomography (CT) revealed an irregular pleural mass invading her left chest wall with rib destruction and pleural effusion. CT-guided needle biopsy revealed diffuse large B-cell lymphoma. Low-dose oral etoposide produced a complete response, and she continued oral chemotherapy for one year after the diagnosis and maintained good performance status. We herein report a very rare case of non-pyothorax-associated lymphoma that nonetheless resulted in great recovery.