Diagnostic challenge in Burkitt lymphoma of the mandible initially misdiagnosed as osteomyelitis: a case report.

Burkitt lymphoma (BL) is a highly aggressive B-cell neoplasm that rarely involves the mandible in elderly without apparent immunodeficiency. We report a case of a 72-year-old male who presented with persistent mandibular pain following extraction of tooth #46. Initial imaging findings were consistent with incipient osteomyelitis, and the patient was treated with antibiotics. Despite treatment, pain persisted, and follow-up imaging revealed swelling and diffusion restriction in the lateral pterygoid muscle without evidence of a distinct mass. Biopsy revealed BL confirmed by immunohistochemistry: CD10+, BCL6+, c-MYC+, Ki-67 >95%, and negative for BCL2, MUM-1, and Epstein-Barr virus. Although c-MYC immunopositivity was demonstrated, fluorescence in situ hybridization for MYC rearrangement could not be performed due to limited tissue, representing a diagnostic limitation. Notably, the patient had no trismus despite deep muscle involvement, but complained of facial paresthesia and showed remote swelling in the scapular area during hospitalization. Systemic staging with imaging, cerebrospinal fluid cytology, and imaging revealed disseminated nodal and extranodal involvement including the central nervous system, corresponding to stage IV disease by Lugano classification. This case highlights the diagnostic challenge of distinguishing lymphoma from osteomyelitis and underscores the importance of considering malignancy in cases of refractory mandibular inflammation with atypical features.