Osteosarcoma of the left maxillary sinus – Case report of an exceedingly rare tumor entity of the paranasal sinuses

Introduction Osteosarcomas as the most common primary malign bone tumors have an incidence of 2-3/ 1.000.000 and mostly affect skeletal bones. The rarer craniofacial osteosarcomas are more challenging to treat because they are usually highly malign, not very responsive to chemotherapy in terms of decreasing in size and more difficult to resect in sano.