Buccal Lymphoma: A Case Report

Abstract

Background Non-Hodgkin’s Lymphoma (NHL) encompasses a diverse group of lymphoid malignancies with varied histopathological and clinical features. Diffuse Large B-Cell Lymphoma (DLBCL) is the most common subtype of NHL, accounting for approximately 30–40% of adult cases. Although primarily arising in lymph nodes, extranodal presentations—especially in the oral cavity—are not uncommon. Oral lymphomas can mimic other neoplastic or inflammatory lesions, leading to potential delays in diagnosis. Case Presentation We report the case of a 41-year-old female patient with a painless swelling on the left side of her face and an associated oral ulceration over the buccal mucosa. She had poorly controlled diabetes mellitus but no significant history of weight loss, fever, or night sweats. Imaging showed a lobulated, heterogeneously enhancing soft-tissue lesion invading the left alveolar ridge and mandibular region. Biopsy of the buccal mucosa revealed large atypical lymphoid cells positive for CD20, PAX5, BCL-6, and CD10, with a Ki-67 proliferative index of ~98%, consistent with Diffuse Large B-Cell Lymphoma (DLBCL), germinal center subtype. The patient underwent six cycles of R-CHOP chemotherapy with significant metabolic remission observed on interim PET-CT scans. She also received prophylactic high-dose methotrexate to minimize CNS involvement. The patient responded well to therapy and was discharged on maintenance follow-up. Conclusion This case highlights an unusual primary presentation of DLBCL in the buccal mucosa. Extranodal lymphomas of the head and neck region can be diagnostically challenging given their broad differential diagnoses. A multidisciplinary approach—encompassing otolaryngology, maxillofacial surgery, oncology, pathology, and radiology—is essential for timely diagnosis. Aggressive regimens such as R-CHOP, with CNS prophylaxis when indicated, can yield favorable outcomes. Early recognition of oral lymphomas is particularly critical in immunocompromised or poorly controlled diabetic patients.