Diffuse large B-cell lymphoma of the maxillary sinus.

: We report the case of a 25-year-old man with a history of recent facial trauma who presented with a mildly painful swelling of the left maxilla and nasal obstruction. The patient was initially diagnosed with left maxillary sinus osteomyelitis secondary to undiagnosed and untreated left maxillary sinus fractures. However, further evaluation revealed that the patient had diffuse large B-cell lymphoma.