Patients with localized primary non‐tonsillar oral diffuse large B‐cell lymphoma exhibit favorable prognosis despite a non‐germinal center B‐cell‐like phenotype

Diffuse large B‐cell lymphomas are detected frequently in the oral cavity. Although tonsillar lymphomas have been rather well characterized, lymphomas originating from non‐tonsillar regions, such as the gingiva, palate, and tongue, have not been well studied. We examined the pathology of clinical samples obtained from 21 patients with localized primary non‐tonsillar oral diffuse large B‐cell lymphoma. Immunohistological examination of CD10, Bcl‐6, and MUM1 determined that 17 of 21 (81%) samples exhibited non‐germinal center B‐cell type, an increased proportion of non‐germinal center B‐cell type compared with previous reports in samples of tonsillar origin (P