OSTEOSARCOMA OF THE ORBIT ASSOCIATED WITH PAGET-DISEASE

Osteosarcoma is a common primary bone malignancy most often involving the long bones and occurring in the second decade of life. Orbital inv olvement in this disease process is rare and is usually due to extensi on of the tumor from an adjacent sinus cavity, Orbital osteosarcoma ar ising from preexisting Paget disease is exceedingly rare. We report th e case of a 78-year-old female patient with Paget disease of the foreh ead who presented with rapidly increasing bilateral proptosis and visu al loss for several months. Examination showed bilateral aphakia, decr eased motility, proptosis with resistance to retropulsion, and tumorou s infiltration of the eyelids and periorbital soft tissue. Fundus exam ination showed marked bilateral scleral indentation without overlying serous retinal detachment. A computed tomographic (CT) evaluation of t he orbits demonstrated extensive soft tissue involvement of the parana sal sinuses, nasal cavity, periorbital soft tissue, and orbits, with c ompression of the optic nerve and globe bilaterally. Biopsy of the per iorbital soft tissue demonstrated osteosarcoma. Radiation therapy fail ed to stem the progression of the disease process, and the patient die d similar to 4 months later. Although osteosarcoma of the orbit associ ated with Paget disease is unusual, it should be considered in the dif ferential diagnosis of older patients with a rapidly progressive orbit al mass.