Tumor and Tumor-like Tumor and Tumor-like Lesion of BoneLesion of Bone

OsteomaOsteoma

• Osteoma is a benign mass protruding froOsteoma is a benign mass protruding from osseous tissuem osseous tissue

OsteomaOsteoma

• Most common tumor of the paranasal siMost common tumor of the paranasal sinuses, most frequently seen in the frontnuses, most frequently seen in the frontal sinus and ethmoidsal sinus and ethmoids

• Two varieties are described: the dense 'iTwo varieties are described: the dense 'ivory' type and 'cancellous' osteomavory' type and 'cancellous' osteoma

Osteoma Lateral radiograph of the skull (a) and axial CT scan (b) demonstrate an ossific nodule (arrow) arising from the outer table of the calvarium

（ a) (b)

Giant cell tumorGiant cell tumor

• Giant cell tumor is a locally Giant cell tumor is a locally aggressive neoplasmaggressive neoplasm

• The sites affected most frequently The sites affected most frequently are the long tubular bonesare the long tubular bones

Giant cell tumorGiant cell tumor

• Clinical manifestation Clinical manifestation

• Earliest manifestations include pain, Earliest manifestations include pain, local swelling, limitation of motion local swelling, limitation of motion and pathologic fractures and pathologic fractures

Imaging featureImaging feature

• On radiographs, the long and short tubuOn radiographs, the long and short tubular bones reveal eccentric osteolytic lesilar bones reveal eccentric osteolytic lesionsons

• With MR imaging, intraosseous fluid levWith MR imaging, intraosseous fluid levels may be seen els may be seen

Giant cell tumor a, b. AP (a) and lateral (b) radiographs of the knee demonstrate an eccentric osteolytic lesion in the proximal tibia. The lesion has a non-sclerotic border and abuts the articular surface of the tibia.

c. Sagittal T1-weighted MR image of the knee demonstrates the low signal intensity mass in the proximal tibia. d. Fat-suppressed T1-weighted MR image after gadolinium adminstration demonstrates enhancement of the mass in the proximal tibia.

Giant cell tumor

osteolytic lesion in the distal radius

soap bubbleexpandabilitySoft tissue swelling

Bone cystBone cyst

• Bone cyst is a usually cavitary lesion of bBone cyst is a usually cavitary lesion of bone. one.

• Bone cysts may occur after trauma and iBone cysts may occur after trauma and in osteoarthritisn osteoarthritis

• These cysts occur most frequently in lonThese cysts occur most frequently in long tubular bones, especially the metaphyg tubular bones, especially the metaphysis, and in the bony pelvis sis, and in the bony pelvis

Imaging featureImaging feature

• Radiographically, these lesions appear rRadiographically, these lesions appear radiolucent and are located centrally, witadiolucent and are located centrally, with cortical thinning and mild expansion oh cortical thinning and mild expansion of the bone f the bone

• CT scanning and MR imaging with contraCT scanning and MR imaging with contrast enhancement reveal presence of fluid st enhancement reveal presence of fluid within the lesion within the lesion

• Complications of simple bone cysts Complications of simple bone cysts include complete and incomplete include complete and incomplete fractures, fractures,

and (rarely) malignant and (rarely) malignant transformationtransformation

Bone cyst Simple bone cyst. AP radiograph of the shoulder demonstrates a pathologic fracture through the simple bone cyst in the humeral metaphysis.

Note the "fallen fragment" within the bone cyst.

OsteosarcomaOsteosarcoma

• Osteosarcoma is a malignant neoplasm Osteosarcoma is a malignant neoplasm of bone composed of proliferating tumoof bone composed of proliferating tumor cells that in most instances produce osr cells that in most instances produce osteoid or immature bone teoid or immature bone

Clinical featureClinical feature

• 75% of cases occurring between the age75% of cases occurring between the ages of 10 and 25 years s of 10 and 25 years

• 86% occur in the long bones with the dis86% occur in the long bones with the distal femoral metaphyseal region tal femoral metaphyseal region

• The next commonest sites are the upper The next commonest sites are the upper tibia and humerus tibia and humerus

Clinical featureClinical feature

• The commonest presentation is pain in tThe commonest presentation is pain in the affected area or, occasionally, a pathhe affected area or, occasionally, a pathological fracture ological fracture

• This tumor metastasises early, particulaThis tumor metastasises early, particularly to the lungs and other bones rly to the lungs and other bones

Imaging featureImaging feature

• On the radiograph, the tumor may be purelOn the radiograph, the tumor may be purely lytic y lytic or sclerotic , or a mixture of the two or sclerotic , or a mixture of the two

Imaging featureImaging feature

• Pure lytic lesionsPure lytic lesions vary from areas of dimini vary from areas of diminished bone density to completely lytic areashed bone density to completely lytic areas with very little reaction from the bones with very little reaction from the bone

• They may have a very thin periosteal reacThey may have a very thin periosteal reaction overlying the lesion with very little evidtion overlying the lesion with very little evidence of new bone formationence of new bone formation

Imaging featureImaging feature

• The sclerotic osteogenic sarcomasThe sclerotic osteogenic sarcomas may may produce a region of dense sclerosis with produce a region of dense sclerosis with loss of the inner cortical margins loss of the inner cortical margins

• The periosteal reaction may be laminateThe periosteal reaction may be laminated or spiculated with so-called 'sunburst' d or spiculated with so-called 'sunburst' appearance appearance

Imaging featureImaging feature

• More often the tumors are both lytic and sMore often the tumors are both lytic and sclerotic with destruction of the bone and clerotic with destruction of the bone and cortex, and extension into the soft tissuescortex, and extension into the soft tissues

• There may be a variable amount of calcifiThere may be a variable amount of calcification in the soft tissuescation in the soft tissues

• a prominent periosteal reaction with a Coda prominent periosteal reaction with a Codman's triangleman's triangle

• MRI:MRI:• The lytic areas of the tumor show a low sThe lytic areas of the tumor show a low s

ignal on T1 and high signal on T2ignal on T1 and high signal on T2• The extension in the medullary cavity is The extension in the medullary cavity is

very accurately determined by MRI, as is very accurately determined by MRI, as is the soft tissue extent the soft tissue extent

Osteosarcoma AP (a) and lateral (b) radiographs of the femur demonstrate a large soft tissue mass with an aggressive periosteal reaction creating the sunburst appearance.

Patchy osteosclerosis and osteolysis in the distal femur

Osteogenic sarcoma Osteolytic sarcoma of the fibular head. There is a small amount of calcification within the tumor.

Osteogenic sarcoma Osteoblastic sarcoma in the upper metaphyseal region of the tibia. There is sclerosis, breach of the cortex and sclerotic extension of the tumor into the tissues. The cortical margin is lost

Osteogenic sarcoma Radiograph of a distal femoral osteogenic sarcoma. On the radiographthere is a mixed sclerotic and lytic lesion with a layered periosteal reaction anteriorly and showing calcification. 

Osteogenic sarcoma The large soft tissue component is well seen on the MR. There is high signal within the lesion and in the medullary cavity