Abstract
BACKGROUND: Diffuse large B-cell lymphoma is the most common subtype of non-Hodgkin lymphomas that remains a major diagnostic challenge due to the variety of its clinical presentations. This case highlights the importance of early biopsy of oral lesions without tendency to heal to attain the diagnosis more quickly. To the best of our knowledge, this study is the first to focus on both oral and pulmonary involvements in a patient with diffuse large B-cell lymphoma. CASE PRESENTATION: The presented case describes an Iranian 18-year-old girl with chronic cough and dyspnea referred for evaluation of the upper jaw due to bone exposure, bone loss, and soft tissue ulceration. Her medical history revealed mediastinal mass, cavitary lesion, and mediastinal lymphadenopathy. However, cytologic and immunohistochemical analysis did not show any evidence of malignancy. In this case a lymphoproliferative disease was suspected but ultimately the oral biopsy diagnosed diffuse large B-cell lymphoma and chemotherapy could be started. CONCLUSIONS: Systemic conditions should be considered as a possible cause of oral lesions and a biopsy should also be performed immediately if there is any doubt concerning the nature of the lesion. Moreover, some conditions necessitate multiple biopsies to attain an accurate diagnosis.