Primary diffuse large B-cell lymphoma of the mandible. A case report

Diffuse large B-cell lymphoma is the most common type of non-Hodgkin lymphoma and is characterized by the appearance of rapidly developing tumor lesions in the lymph nodes, spleen, liver, bone marrow or other organs. Primary extranodal presentations of this entity in bone are rare (5% of all extranodal lymphomas) and their initial manifestation is usually in the form of a single bone lesion. This paper addresses a case of a 62-year-old male diagnosed with diffuse large B-cell lymphoma in the mandible. The patient had left mandibular swelling with intermittent paresthesia of the left lower lip and chin, without apparent neck adenopathies. No other locations were identified in the several exams performed, and the final diagnosis was an asymptomatic diffuse extranodal large B-cell lymphoma (IE-A) in the body of the left mandible. Four cycles of chemotherapy were given according to the R-CHOP protocol (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisone) plus external radiotherapy targeted to the involved site, resulting in complete remission of the tumor. Such lesions are fairly uncommon in daily clinical practice. However, considering their severity and the importance of an early diagnosis, such conditions should be included in the differential diagnosis of bone lesions in the orofacial region.