Sporadic Burkitt Lymphoma Mimicking Osteomyelitis of the Mandible Revealing Clinically Unsuspected HIV Infection.

Adult sporadic Burkitt lymphoma is a rare and highly aggressive malignancy, accounting for approximately 1-2% of adult lymphomas in Western countries, and exclusively intra-oral localization is very uncommon. We describe a rare case of a moderately painful sporadic Burkitt lymphoma localized in the posterior third of the left mandibular bone, initially misdiagnosed as osteomyelitis-like lesion, in a patient Epstein-Barr virus infection-negative with unknown human immunodeficiency virus (HIV) positivity and acquired immunodeficiency syndrome. A 52-year-old man was referred to our Department complaining of persistent moderate pain localized in the left mandibular arch. According to clinical and radiological features, a diagnosis of post-extraction osteomyelitis was made and a surgical revision, including soft and hard tissue biopsy, was performed. Histopathology revealed the presence of a diffuse proliferation of lymphoid cells, exhibiting the typical 'starry-sky' appearance that was consistent with the diagnosis of B-type non-Hodgkin lymphoma. Unexpectedly, HIV seropositivity was also found, but the patient was unaware of this, and the history did not reveal any particular risk factor for HIV infection. Positron-emission tomography showed a highly (18)F-fluorodeoxyglucose-avid mass in the left maxillofacial region and extensive disease in bone marrow and mediastinum. Thus, the patient was referred to our onco-hematological team for final assessment and care. In conclusion, sporadic Burkitt lymphoma is an aggressive malignancy, which rarely affects adults with initial intra-oral manifestations. In the presence of abnormal gingival or alveolar lesions, a non-odontogenic disease should be suspected and the appropriate diagnostic test should be performed.