Primary liposarcoma of the orbit: a clinicopathologic study of seven cases.

Liposarcoma, the most common soft tissue sarcoma in adults, will rarely involve the orbit, either primarily or as a metastasis. We describe seven primary orbital liposarcomas, representing the largest documented series of primary orbital liposarcoma to date. Affected patients were three males and four females ranging in age from 28 to 69 years (median, 51 years). Five patients presented with painless proptosis, one patient had painful proptosis, and no details of presenting symptoms are available in one case. The site distribution was retrobulbar (3 cases), lateral orbital wall (2 cases), medial wall (1 case), and unspecified (1 case). Radiologic impression included hemangioma, lipoma, and an inflammatory process. Lesional size ranged from 2.8 to 4 cm. Five liposarcomas were purely well-differentiated, one was dedifferentiated, and one was pleomorphic in type. The well-differentiated cases comprised the following subtypes: spindle cell (2 cases), adipocytic (2 cases), and combined adipocytic/sclerosing/inflammatory (1 case). Five patients underwent orbital exenteration (one followed by radiation) and two had marginal/partial excision of their tumors. Follow-up was available for five patients, ranging from 13 to 204 months (median 65 months). Four patients showed no evidence of recurrence, including the patient with pleomorphic liposarcoma who had a long, disease-free survival (65 months) following marginal excision. One patient has had multiple recurrences following initial partial excision. One patient died of an unrelated cause with no clinical evidence of recurrence. Despite the difficulty in obtaining wide surgical margins, the small tumor size at presentation and the apparent predominance of the well-differentiated type means that the prognosis for orbital liposarcoma is generally good. In view of the various morphologic patterns that may occur, liposarcoma should be considered in the differential diagnosis of any histologically unusual mesenchymal lesion in the orbit.