Extraosseous osteogenic sarcoma following an intramuscular injection.

A 29-year-old white male with an extraosseous osteogenic sarcoma is reported. He first noted a nodule at the site of eventual tumor development some eight years previously, following an intramuscular penicillin injection. Treatment consisted of wide surgical excision and radiation therapy, and he remains healthy some 8 months later. To our knowledge this represents the first case of extraosseous osteogenic sarcoma occurring at the site of a previous intramuscular injection.