BackgroundDiffuse large B-cell lymphoma (DLBCL) is the most common type of lymphatic tumor; however, extranodal DLBCLs that exhibit initial symptoms in the maxilla and mandible are rare. Moreover, DLBCL is clinically classified as a moderate to highly malignant lymphatic tumor that can progress rapidly; therefore, early diagnosis is crucial. However, diagnosis is difficult because the disease causes a diverse range of clinical symptoms with no characteristic imaging findings. We conducted a clinical investigation to clarify the clinical characteristics of DLBCL exhibiting initial manifestation in the maxilla and mandible.MethodsOf the 2748 patients with malignant tumors of the oral and maxillofacial region examined during a period of 11 years between January 2006 and December 2016 at our hospital, 27 primary cases diagnosed with DLBCL based on the chief complaint of symptoms in the gingiva and bone of the maxilla and mandible were enrolled. We evaluate on sex, age, whether treatment was provided by a previous physician, symptoms, disease period until seeking treatment, clinical diagnosis, laboratory findings, and imaging results.ResultsThere were 15 cases with maxilla involvement and 12 with mandible involvement. The median disease period until seeking of treatment was 60 d (3–450 d). All cases exhibited a tumor or a mass, and hypoesthesia of the chin was confirmed in 8 cases with mandible involvement. The clinical stage was stage I in 8 cases, stage II in 10 cases, and stage IV in 9 cases. Serum lactate dehydrogenase (LDH) levels were elevated in 13 of 22 patients. The overall survival rate was 63%.ConclusionThe possibility of Malignant Lymphomas (MLs), such as DLBCL, must be considered while treating lesions of the oral and maxillofacial region.