Novel case report of primary osteosarcoma of the maxilla in an adult: An important differential diagnosis

Craniofacial osteosarcoma accounts for 10% of osteosarcoma malignancies, typically affecting the 4-5th decade of life, with the maxilla being the second-most common site.

We report a 58-year-old male, non-smoker, with a lump of his upper jaw which occasionally bled during mastication. Clinical examination revealed an exophytic mass in the upper left tuberosity of the maxilla and no lymphadenopathy, where initial differential diagnosis was squamous cell carcinoma.

Radiological investigations revealed a metabolically active left maxillary lesion with maxillary sinus destruction, representing primary malignancy. Histological analyses initially suggested a fibro-osseous lesion; further immunohistochemistry showed cytokeratin AE1/AE3/CK(MNF.116) positivity with 60% ki67 proliferation index; diagnostic of grade 2–3 osteosarcoma. Management included neoadjuvant chemotherapy prior to total maxillectomy and dental prosthetic rehabilitation.

We report a novel case of primary osteosarcoma of the maxilla in an adult. Osteosarcoma is challenging to diagnose and an important differential to consider where the mainstay of treatment is early invention.