Bone Tumors (mostly occur in cortex)

5 benign and 2 malignant

Cartilage tumors (mostly occur in medulla)

1 benign and 1 malignant

Benign Tumors of Bone

Tumor Type Location Special Feature
Osteoma Facial bones associated w/ Gardner's polyposis syndrome
Osteoid Ostema Diaphysis of proximal femur radiolucent focus surrounded by sclerotic bone;vertebral pain relieved by ASA
Osteoblastoma Vertebra pain is NOT relieved by ASA
Osteochondroma Metaphysis of distal femur 4'M's -Most common; Male; Medullary location;Mixed name
Giant Cell around knee (proximal tibia or distal femur)Epiphysis; more common in females; soap-bubble appearance on X-ray; Multinucleated giant cells

Malignant Tumors of Bone

Osteosarcoma

Variants:

  1. Conventional: osteoblastic, chondroblastic, fibroblastic OS
  2. Telangiectatic OS
  3. Small cell OS
  4. Low-grade central OS
  5. Periosteal OS
  6. Paraosteal OS
  7. Secondary OS
  8. High-grade surface OS
  9. Extraskeletal OS

Secondary osteosarcoma may be seen following radiation therapy, or may be associated with underlying bone lesions such as Paget's disease, fibrous dysplasia, bone infarction and chronic osteomyelitis. Other types of sarcoma may also be seen with these conditions, including fibrosarcoma and malignant fibrous histiocytoma. The prognosis for these secondary sarcomas is often grave.

Telangiectatic osteosarcoma is an entirely lytic lesion, reflecting minimal osteoid production in the tumor. Far less common than conventional osteosarcoma, it was previously felt that the telangiectatic form carried a worse prognosis. More recent studies have shown a similar or even better prognosis, as the telangiectatic form is especially sensitive to preoperative chemotherapy.