[One case of primary malignant lymphoma of the maxillary sinus].

Malignant lymphoma of the maxillary sinus is very rare. A case of diffuse large B-cell lymphoma (DLBCL) of the left maxillary sinus is presented here. A 59-year-old man came to our hospital complaining of swelling under the left lower eyelid without any other symptoms. Imaging examination including CT and MRI detected a tumor in the left maxillary sinus. The tumor was invasive into left orbit. The biopsy revealed a diffuse large B-cell lymphoma. The tumor cells were positive to CD20, CD79a, CD45. In conclusion, a very rare case of DLBCL of the maxillary sinus was reported.