BONE TUMOUR RADIOLOGY
1. Clues by appearance of lesion
2. Clues by location of lesion
3. Clues by type of periosteal reaction
4. Clues by matrix of lesion
5. Clues by density of lesion
6. Clues by number of lesion
1. Clues By Appearance Of Lesion
Patterns of Bone Destruction
1. Geographic
2. Moth-eaten
3. Permeative
Geographic Bone Destruction
Destructive lesion with sharply defined borderImplies a less-aggressive, more slow-growing, benign processNarrow transition zone
Examples:
1. Non-ossifying fibroma
2. Eosinophilic granuloma
NON OSSIFYING FIBROMA
30 to 40% children over two years have one or more lesions.Most common between 8-20 years of ageUsually occur in metaphysis of one (75%) or more (25%) of the tubular bonesMost lesions heal spontaneously by being replaced with normal bone.May undergo pathologic fracture.Do not undergo malignant transformation
NON OSSIFYING FIBROMA - X-ray characteristics:
* Geographic* Lytic* Multilobulated* Metaphyseal* Usually intramedullary* Eccentric* Well-marginated* Sclerotic rim* Endosteal scalloping
Non-ossifying fibroma of tibia
Eosinophilic Granuloma
Solitary, non-neoplastic proliferation of histiocytes.Part of a spectrum of Langerhan's cell histiocytosis, formerly known as histiocytosis X.Localized lesion in bone or lung and occurs most commonly in children aged 5 to 10.EG is found in the diaphysis or metaphysis of long bones in the center of the medullary cavity.The radiologic differential includes Ewing's sarcoma, osteosarcoma, metastases and osteomyelitis.
Eosinophilic granuloma of femur
Moth-eaten Appearance
Areas of destruction with ragged bordersImplies more rapid growth - High probability of malignancyExample:1. Myeloma2. Metastases3. Lymphoma4. Ewing's sarcoma
Multiple myeloma
Multiple myeloma is a malignant tumor of plasma cells that causes widespread osteolytic bone damage.The average patient age is over 50 years old and men are affected twice as often as women.Characterized by irregular lytic defects of different sizes.These lytic areas are often described as "punched out" and have no periosteal reaction.Erosion begins intramedullarly and progresses through the cortex.
Multiple myeloma of humerus with pathological fracture
Permeative Lesion
Ill-defined lesion with multiple "worm-holes"Spreads through marrow spaceWide transition zoneImplies an aggressive malignancy -Round-cell lesionsExamples:1. Lymphoma2. Leukemia3. Ewing's Sarcoma4. Myeloma5. Neuroblastoma6. Osteomyelitis
2. Clues By Location Of Lesion
1. In the transverse plane:
a) Central - Enchondroma
b) Eccentric -GCT, osteosarcoma, chondromyxoid fibroma
c) Cortical - Non-ossifying fibroma, osteoid osteoma
d) Parosteal - Parosteal osteosarcoma, osteochondroma
2. In the longitudinal plane:
a) Epiphyseal - GCT, chondroblastoma
b) Metaphyseal - Osteomyelitis, osteosarcoma
c) Diaphyseal - Round cell lesions, ABC, enchondroma
Osteoid osteoma
Osteoid Osteoma is a benign bone lesion with a nidus of less than 2 cm surrounded by a zone of reactive bone.Osteoid osteoma has a distinct clinical picture of dull pain that is worse at night and disappears within 20 to 30 minutes of treatment with non-steroidal anti-inflammatory medication.4 diagnostic features include
(1) a sharp round or oval lesion
(2) less than 2 cm in diameter,
(3) has a homogeneous dense center
(4) a 1-2 mm peripheral radiolucent zone.
Osteoid osteoma of transverse process of vertebra
Osteoid osteoma of fibula
Characteristic Location
Simple bone cyst - Proximal humerus
Chondroblastoma - Epiphyses
Giant Cell tumor - Epiphyses
Adamantinoma - Tibia
Chordoma -Sacrum
Osteoblastoma - Posterior element of spine
Parosteal osteosarcoma - Distal femur
Periosteal osteosarcoma - Tibia
Chondrosarcoma - PelvisSIMPLE BONE CYST
Solitary cystic lesion over the proximal humerus.Multiple septations.Thinned out cortex.Sclerotic border with narrow zone of transition signifies a benign process.Note: abscence of periosteal reaction differentiates it from aneurysmal bone cyst. (Find out more in my lens on lytic bone lesion).
Solitary bone cyst of femur CHONDROBLASTOMA
Chondroblastomas are radiolucent lesions that typically occupy the epiphysis (or apophysis) of long bones.They tend to be small (<> Chondroblastoma of distal femur
chondroplastoma of femur
GIANT CELL TUMOUR
X Ray finding:Solitary expansile lytic lesionMultiple septation (soap bubble appearance)No reactive sclerosisMetaphyseal regionAdjacent to epiphyseal lineJusta-articular if epiphyseal plate is fused
Giant Cell Tumour
Characteristic X Ray finding:Solitary expansile lytic lesionMultiple septation (soap bubble appearance)No reactive sclerosisMetaphyseal regionAdjacent to epiphyseal lineJusta-articular if epiphyseal plate is fused
Giant cell tumour of distal radius
ADAMANTINOMA - TIBIA
Adamantinoma is a locally aggressive osteolytic tumor that is found 90% of the time in the diaphysis of the tibia with the remaining lesions found in the fibula and long tubular bones.Adamantinoma appears as an eccentric, well-circumscribed, and lytic lesion on plain x-ray.The lesion usually has several lytic defects separated by sclerotic bone.There is cortical thinning but little periosteal reaction.
3. Clues By Type Of Periosteal Reaction
Benign - None or Solid periosteal reactionMore aggressive or malignant1. Lamellated or onion-skinning2. Sunburst3. Codman's triangle(More explanation in my lens on Periosteal Reaction)4. Clues By Matrix Of Lesion
1. Ossification (Osteoblastic process) - Well organized ossified mass with fluffy, cotton-like or cloud-like densities. Eg. Osteosarcoma.2. Calcification (Cartilaginous process)- Unorganized calcified matrix which is comma-shaped, punctate, annular or popcorn-like. Eg. Enchondroma, Chondrosarcoma, Chondromyxoid fibroma.OSTEOSARCOMA
Well organized mass signifying osteoblastic process.Sunburst periosteal reaction and soft tissue mass signifies an aggressive and rapidly growing tumour. Osteosarcoma of distal femur
CHONDROSARCOMA
Calcified matrix (unorganized) signifies cartilaginous tumour.The wide zone of transition and cortical break without periosteal reaction signifies a rapidly growing and aggressive type of tumour
Chondrosarcoma of left ilium. Note the extensive calcification.
5. Clues By Density Of Lesion
1. Sclerotic Cortical lesions- Osteoid osteoma- Brodie's abscess- Stress fracture
2. Lytic lesions in children- Eosinophilic granuloma- Neuroblastoma- Leukemia
3. Lytic lesions in adult- Metastatic lesions (Lung, Kidney, Thyroid)- Multiple myeloma- Primary bone tumor
4. Blastic lesion in children- Medulloblastoma- Lymphoma
5. Blastic lesion in adult- Metastatic disease (Breast, Prostate)- Lymphoma- Paget's disease6. Clues by number of lesion
Multiple lesion: More often benignMalignancies with multiple lesions- Metastatic disease- Multiple myeloma- Lymphoma
Reference : Squido.com