Name : Akbar
Affiliation : Temple University School of Medicine
Academic Degree: Emeritus Professor of Radiology and Former professor of Orthopedic Surgery
Resident : ----------------
Gender : Female
Age : 31
31 year-old female, no clinical history
Imaging Procedures and Findings
Right hip plain radiograph (image 1) demonstrates two (a large well-defined and a small ill-defined) calcified nodules in right inguinal region. Distal metaphysis of the right femur (image 2) shows dense and eburnated tumor with sunburst periosteal reaction and new bone formation. There is extension into the soft tissues. These findings are consistent with Osteosarcoma and inguinal lymph node metastases. Lateral skull radiograph (image 3) reveals parallel cortical calcifications suggesting the tram-track sign in Sturge-Weber syndrome. However, it does not mean that there is any relationship between SWS and osteosarcoma unless further significant number of cases is reported.
Osteosarcomas usually arise in the metaphyseal portion of long bones, most frequently at the distal end of the femur, the proximal end of the tibia, and the proximal end of the humerus. Osteosarcomas, radiographically, produce all varieties of bone change. They may be extremely dense, or vary but little from the normal, or cause almost total bone destruction, or present as an admixture. Almost invariably the periosteal reaction admixed with new bone formation along the vessels in osteosarcoma is highly irregular and interrupted. The "sunbursts" and "onion-peel" types of periosteal response are classic examples. The osteoblastic responses are generally referred to as "reactive bone," "new bone formation," or just "increased bone density," appellations as nonspecific as their roentgen appearances. Usually benign bone responses are sharply demarcated and easily differentiated from their surroundings. Malignant neoplastic responses lack this differentiation; their borders blend imperceptibly with surrounding bone. Sometimes osteoblastic responses display characteristic bone patterns, with trabeculae and haversian canals, and may very properly be called "new bone" formation. New bone formations may be benign or malignant; radiographically they are differentiated by the uniformity of their density and margins. The less uniform the density and the less definite the margins, the greater the likelihood of their being malignant. The tram-track sign is seen on skull radiographs as gyriform, curvilinear, parallel opacities that have the appearance of calcifications. The tram-track sign is produced by cortical calcifications that result from leptomeningeal vascular malformations found in patients with Sturge-Weber syndrome.
Osteosarcoma with proximal lymphadenopathy and Sturge-Weber syndrome
1-Bonakdarpour, A. Reinus, W. R. and Khurana, J. S.: Diagnostic Imaging of Musculoskeletal Diseases, A Systematic Approach. Springer, 2010, PP 265-273 2- Edeiken J: Roentgen Diagnosis of Diseases of Bone, 2nd ed. Baltimore: Mosby, 1978, pp 939-966. 3-Akpinar E. The Tram-Track Sign: Cortical Calcifications. Radiology. 2004; 231:515-516.