Extraskeletal Osteosarcoma of the Orbit

Patient. We report a 22-year-old male presenting with extraskeletal osteosarcoma of the orbit. Discussion. Extra skeletal osteosarcomas are uncommon tumours, usually arising from the lower extremities or girdle. These are aggressive tumours with high metastatic potential and poor outcome. Optimal treatment is undefined, and the role of radical surgery, radiotherapy and aggressive chemotherapy is currently being evaluated. The orbit is a rare site for extraskeletal osteosarcoma, with the only previous case reported in an 11-year-old male, who was irradiated in infancy for a retinoblastoma.


C ase report
A twenty-tw o-year-o ld m an presented with a 1-year history of gradually increasing sw elling of the left eye and occasional pain. On the w hole, patient was w ell nourished and had no evidence of lym phnode enlargement. There was proptosis of the left eye w ith oedem a in the upper eyelid. T he conjunctiva showed m ild congestion, and the cornea, anterior cham ber and lens were clinically norm al. V ision and ocular m ovem ents w ere norm al. T here was no evidence of raised intra-cranial pressure, m eningeal irritation or focal neurological de® cits. All other system s were norm al.
Blood count and serum chemistry were norm al. C T scan of the head revealed a well-circum scribed hom ogeneous m ass in the supero-m edial aspect of the left orbit, with non-hom ogeneous contrast enhancement (Fig. 1). T he m ass appeared separate from the globe and the bony orbital w all. O n M RI, the lesion w as hom ogeneously hypo -intense on T 1and hyper-intense on T2-weighted im ages. T he patient underwent left frontal transcranial orbitotom y and com plete excision of the orbital tum our. At surgery the tum our w as found not attached to the orbital walls or extra-ocular m uscles. It was separated by blunt dissection and entirely rem oved with-w F ig. 1. C T scan of the head show ing the intra -orbital tum our. usually present in the fourth and ® fth decades of life in contrast to their osseous counterparts. 1± 4 Som e series report a male predom inance, w hereas others show no sex predilection. 3,5 The extremities and girdles, especially lower, are m ost com m only involved. 5 There are also reports of such tumours involving the face, breast, abdom inal wall, soft tissues of the back and retroperitoneum. 2,3,5 Fine and Stout reported a case of osteogenic sarcom a arising at the site of a vaccination scar. 5 K auffm an and Stout reported the case of an 11-year-o ld boy developing orbital extraskeletal osteosarcom a, following radiation therapy for retinoblastom a in infancy. 6 T he role of traum a in the development of extraskeletal osteosarcom as is controversial, though a history of traum a can be elicited in 13% of patients with these tum ours. 3 T he insidious evolution of osteogenic sarcom a in m yositis ossis® cans w as described by Shanoff et al. 7 and around 16% of extraskeletal osteosarcom as have developed in m yositis ossi® cans. 5 Radiotherapy is known to predispose to the developm ent of both soft tissue and bone sarcom as. In a series by Sordillo   Post-operative scanning show ed no evidence of residual disease in the orbit, and C T scans of the chest and abdom en and radionucleide bone scan showed no evidence of disease elsewhere. T he patient was unwilling to undergo orbital exenteration or local radiotherapy. He received six cycles of com bination chem otherapy w ith cisplatin, ifosfam ide and doxorubicin and is alive and free of disease 2 years after diagnosis.

D iscussion
Extraskeletal osteogenic sarcom a is unusual and reportedly accounts for only 2± 4% of osteosarcom as. 1± 4 Patients with extraskeletal osteosarcom as volvem ent being lung, regional lym ph nodes and bone. 5,10± 12 Treatm ent of these tumours has traditionally been radical surgery w ith or without additional radiation. V arious chem otherapy protocols have been used in advanced and metastatic disease and the outcom e was uniform ly poor. In the series by Sordillo et al., 2 four of the ® ve patients who received adjuvant chem otherapy after surgical excision of recurrent or m etastatic disease were long-term survivors, suggesting that chemotherapy may be of value in an adjuvant setting.
W ith the increasing use of chem otherapy, organ preservation could becom e feasib le in patients with extraskeletal osteosarcom a. The use of pre-operative intra-arterial adriam ycin infusion and gel em bolisation followed by w ide excision of the tum our was reported by D hillon et al. for achieving lim b preservation. 12 O ur experience also suggests that preservation of organ/function could be achieved with lim ited surgery and chemotherapy. Chem otherapy schedules like C yAD IC (cyclophospham ide, doxorubicin, and dacarbazine) or M AID (M esna, ifosfam ide, doxorubicin and dacarbazine) are currently being tried to evaluate response of these tum ours prior to surgery. 13 Though de® nitive guidelines cannot be m ade, current data suggest that the optim al m anagem ent of these aggressive tum ours involves the use of chemotherapy and organ-preserving surgery with or without additional radiotherapy.

A cknowledgem ent
T he authors gratefully acknowledge D r. Cyril Fisher, at the D epartm ent of Pathology, The Royal M arsden N H S T rust, London, for kindly review ing the histopathology slides and con® rm ing the diagnosis.
Localised pain, swelling and oedem a are the comm onest presenting sym ptom s. 3 D uration of sym ptom s vary from weeks to years and most series report an average duration of 4± 6 m onths. 2,3 Radiologically the lesion presents as a soft tissue m ass with spotty to m assive calci® cation, without evidence of bony involvem ent. 2,4 Findings on m agnetic resonance im aging are non-speci® c, though m ost tum ours w ere heterogeneous and hyper-intense to m uscle on T1-weighted im aging, and dem onstrated high signal intensity on T2-weighted im aging. 8 M icroscopic features of extraskeletal osteogenic sarcom as are sim ilar to those of the prim ary osseous variety, though m ost tumours are poorly differentiated and of high grade. 3 Variations in the am ount of osteoid, cartilaginous and ® brous tissue have prom pted m ost authors to classify the tum ours as osteolytic, osteosclerotic or chondroblastic. 4,5 Fibroblastic zones generally show sm all uniform spindle cells. Large and pleom orphic cells and interlacing bundles of spindle cells are occasional ® ndings. 3,9 Vascular invasion of the tum our is rare, and areas of necrosis are seen in som e specimens. 3 Prim ary extraskeletal osteosarcom as have a very aggressive natural history and local recurrences are com m on after incom plete excision, especially without additional radiotherapy. 2,9 M ost patients die from m etastatic disease, the com m on sites of in-