Low grade central osteogenic sarcoma. A long-term followup of 20 patients.

Osteogenic sarcoma is a heterogeneous family of tumors that has a variable biologic behavior. Low grade central osteogenic sarcoma is an uncommon form that is characterized by a long premorbid history and is compatible with prolonged survival after treatment. Twenty cases of low grade central osteosarcoma with long-term followup (16 [2.5-48] years) were studied retrospectively. The age distribution was broad (range, 15-83 years). All tumors arose in the lower limb. The primary symptom was pain; mean duration was 44 months (range, 1-180 months). A diagnosis of low grade central osteosarcoma was made primarily for 11 patients. For 9 others, fibrous dysplasia (3), nonossifying fibroma (2), fibroma (1), chondromyxoid fibroma (1), chondrosarcoma (1), and simple bone cyst (1) were diagnosed initially. Intralesional surgery was associated with recurrence in every case. Radical margins were not associated with local recurrence. Four recurrences were higher grade and 1 was dedifferentiated. Three of 4 patients with metastases died of their disease. Five- and 10-year survival was 90% and 85%, respectively. Histology and radiology are complementary for confirming the diagnosis. Low grade central osteosarcoma seems to be controllable by surgery alone if at least wide margins are used.