Tumor and tumor-like processes

Question 1

What is the most common source of osteoblastic metastatic carcinoma in adult females?

Answer 1

Breast Cancer

Question 2

List the three common causes of solitary sclerotic vertebral body/ivory vertebra.

Answer 2

1. Hodgkin’s lymphoma (anterior scalloping)
2. Osteoblastic mets
3. Paget’s disease – cortical thickening and expansion

Question 3

Is it common to find a tumor involving a joint?

Answer 3

No

Question 4

Is multiple myeloma more common in the vertebral body or neural arch?

Answer 4

Vertebral body

Question 5

What malignancy demonstrates as a cold bone scan?

Answer 5

Multiple Myeloma

Question 6

Which is the most dense (white on x-ray) primary malignant bone tumor?

Answer 6

 Osteosarcoma (2nd most common primary malignant bone neoplasm)

Question 7

What is the common age range of primary osteosarcoma?

Answer 7

10-25 years old (in older pts, likely dt malignant degeneration of benign process)

Question 8

What is the difference between sunburst and onion skin appearance?

Answer 8

Sunburst – seen in hemangioma, lytic skull lesions with striations in a “sunburst” or “spoked wheel” pattern 
characteristic of osteosarcoma

 Onion skin – layered or laminated periosteal rxn created by several parallel concentric layers or lamellae of periosteal new bone
implies a more aggressive process, but can be dt both benign and malignant conditions
most characteristic of Ewing’s sarcoma but could be found in osteosarcoma, osteomyelitis, stress fxs, eosinophilic granulomas in very young pts

Question 9

Which part of the long bone is commonly involved in osteosarcoma?

Answer 9

Metaphysis – especially in distal femur, proximal tibia and proximal humerus

Question 10

What is codman’s triangle?

Answer 10

When the periosteum lifts off of the cortex, creating triangular layers that form at the margin of the lesion, often in osteosarcomas (also seen in osteomyelitis)

*triangle itself is usually tumor free

Question 11

Why is Ewing’s sarcoma commonly found in the diaphysis of long bone?

Answer 11

Because it arises from the red bone marrow, which is mainly in the diaphysis and is closely related to reticulum cell sarcoma

Question 12

What is a geographic lytic appearance and does it suggest more benign or aggressive neoplasms? What are the other two lytic appearances of tumors?

Answer 12

Geographic lytic appearance = confined to a relatively specific area that is more or less easily defined, more likely to be benign

Other two types:
Moth eaten
Permeative

Question 13

Which condition presents as a solitary exostosis that points away from the nearest joint?

Answer 13

Osteochondroma

Question 14

Compare the incidence of malignant transformation in osteochondroma and hereditary multiple exostosis.

Answer 14

Osteochondroma: malignant degeneration in 1% (solitary)

Hereditary Multiple Exostosis: 20% malignant degeneration

Question 15

What is a “corduroy vertebra”?

Answer 15

Corduroy cloth appearance of vertebrae, seen in hemangioma due to lytic lesions with coarse vertical striations

Question 16

Is spinal hemangioma commonly solitary or polyostotic?

Answer 16

Solitary

Question 17

Which is the most common benign bone tumor of the spine?

Hemangioma

Answer 17

Hemangioma
age 40 and up
usually asx – can have pain or muscle spasm occasionally
neurological compromise due to ballooning of vertebral body, extension of tumor into central canal, pathologic fx, hemorrhage
75% found in spine and skull
usually in vertebral body, 10-15% into arch
usually solitary
body expansion is rare

Question 18

Is a bone island symptomatic?

Answer 18

Bone Island = Enostoma

• Usually asymptomatic
• Occurs in pelvis, sacrum, proximal femur, and any bone except skull
• compact lamellar bone in spongiosa
• can look like blastic mets on an xray

Question 19

Which benign tumor classically demonstrates as pain worst at night and easily relieved by aspirin?

Answer 19

Osteoid Osteoma 
pain refers to nearby joint
usually in kids
can cause painful, rigid scoliosis
can occur in any bone (50% in femur and tibia, 20% phalanges, 10% spine)
tends to be in cortex of bone

Question 20

Which part of the bone is usually involved with osteoid osteoma?

Answer 20

Cortex:

see increased opacity on xray, actual lesion is lucent (but usually

Question 21

What is the appearance of the tumor matrix in enchondroma?

Answer 21

Cartilaginous lesion inside the cartilage 
thinned cortex
endosteal scalloping
stippled calcification
Asx, but can cause pathologic fx 
Age 10-30
Can happen in any bone with cartilage
Most common tumor of phalanges
Can potentially transform to chondrosarcoma (think pain – if no pain, likely benign)

Question 22

What is multiple enchondromatosis called?

Answer 22

Two types:
1.Ollier’s Disease
usually unilateral, monomelic (may cause growth change, shortened limb)
malignant transformation rate 25-50%

2.Maffucci’s syndrome (Below, can see phleboliths)
soft tissue hemangiomas
phleboliths
greater risk of malignant transformation than Ollier’s

Question 23

What is the most common location of fibrous cortical defect?

Answer 23

In cortex of bone in lower extremity: tibia or fibula, also humerus, ribs, ilium
2-8 years old

Question 24

What is a fallen fragment sign associated with?

Answer 24

Simple Bone Cyst 

Fallen fragment = piece of cortex falls off into cyst and sinks to bottom

Question 25

Which benign bone tumor is named according to its appearance rather than its histological composition?

Answer 25

Aneurysmal Bone Cyst – cystic, blood filled cavity, “aneurysmal” dt appearance 

Question 26

Describe the radiographic difference between an enchondroma, simple bone cyst, aneurysmal bone cyst and osteochondroma.

Answer 26

1. Enchondroma (see photo previous page top right)
Geographic lytic
Expansile
Thinned cortex, endosteal scalloping
Metaphyseal-diaphyseal
Most central
Calcification in 50%
No periosteal rxn, no soft tissue mass

2. Simple Bone Cyst (see photo on previous page)
   Ages 3-4
   Asx
   2/3 undergo pathologic fx
   fluid-filled cyst
   75% in proximal humerus or femur
   “fallen fragment” sign with fracture – piece of cortex falls into cyst and sinks to bottom of it
3. Aneurysmal Bone Cyst (see photo above right)
   expansile
   lytic, septated
   eccentric
   markedly thinned cortex
   metaphyseal, may extend to epiphysis (only benign tumor to cross growth plate)
   periosteal response more common

4. Osteochondroma (see photo page 12)
bony exostosis: cortex continuous with host bone; normal trabeculae
cartilaginous cap may calcify
project away from joint
sessile produces asymmetric widening

Question 27

Is giant cell tumor painful? Is it malignant?

Answer 27

Yes, Painful!

“Quasimalignant” – 20% malignant, 80% benign

Question 28

Is Paget’s disease monostotic or polyostotic?

Answer 28

 Polyostotic

Right side more common than left

Question 29

List the radiographic features of Paget’s disease in a long bone such as the femur or tibia.

Answer 29

In Long bones – thickened cortex, bowing deformities (saber shin = shin that looks like a curved sword), shepherd’s crook deformity = thickening of cortex plus bowing, blade of grass (candle flame or V-shape) – looks like cut piece of grass or tip of flame (lytic appearance)

Skull: osteoporosis circumscripta (circumscribed, outlined lytic area ), cotton wool appearance (spots all over skull)
Jaw – increased size
Spine – ivory vertebrae, picture frame vertebra (thickened cortex)
Pubic Bone – unilateral, “brim sign” – thicker on one side than the other (below)
In General:
increased or decreased bone density
coarsened less distinct, trabeculae
thickened cortex (less distinct)
bone expansion
subarticular extension
pseudofractures (similar to insufficiency stress fx)
deformities (like bowing)
pathologic fx (mild trauma causes bone to break)

Paget’s disease general info:
rare before age 40, usually over 55
mostly asx, found incidentally on xray of low back
most common sx: dull, boring pain
temperature of involved area may increase
see enlargement of bone – causes mass effect on surrounding structures
can have heart problems bc vascular lesions – cause heart to work harder