Case Report of Maxillary Alveolar Rhabdomyosarcoma Misdiagnosed as Periapical Lesion: Clinicopathological Alerts and Life-Saving Lessons for Dentists.

This report describes a rare case of alveolar rhabdomyosarcoma initially presenting with clinical features resembling an endodontic lesion. A 15-year-old male presented with progressive right maxillary swelling initially treated as a dental abscess. Radiographic examination revealed a poorly defined destructive lesion associated with the apices of teeth #14-18, exhibiting expansion and destruction of the maxillary sinus walls. Additional imaging demonstrated a contrast-enhancing soft tissue mass with extensive local invasion. Histopathological examination confirmed alveolar rhabdomyosarcoma that was positive for myogenin, myoD1, CD56 and desmin, with a Ki-67 proliferation index of 80%-90%. This case highlights that approximately 3% of non-endodontic periapical lesions are malignant, reinforcing the importance of thorough clinical, radiographic and histopathological examinations for lesions demonstrating atypical features. Dentists should maintain vigilance when evaluating periapical lesions, particularly those with atypical presentations or unresponsive to conventional therapy.