Abos - Orthopaedic Oncology:specific Neoplasms:other Commonly Tested Lesions Involving Bone

Front 1

What age group is particularly at risk?

Back 1

Age <2O years old

Front 2

ls an ABC generally painful?

Back 2

Yes

Front 3

What are the three most common anatomic locations?

Back 3

Femur
Tibia
Posterior spine

Front 4

Are ABCs usually located centrally within bone?

Back 4

No; eccentric

Front 5

Are ABCs usually lytic or blastic?

Back 5

Lytic with thin periosteal rim

Front 6

Where might an ABC extend into?

Back 6

Adjacent soft tissue

Front 7

What is the classic MRI feature of an ABC?

Back 7

Fluid-fluid levels

Front 8

What are the histologic features?

Back 8

Cavernous spaces without endothelial lining

Front 9

What has a similar histology? Key difference?

Back 9

Hemangioma (similar histology with epithelial lining)

Front 10

lf a very cellular stroma is present, what diagnosis must be considered?

Back 10

Telangiectatic osteosarcoma

Front 11

What is the usual treatment for an ABC?

Back 11

Curettage and bone graft

Front 12

ABCs are most likely to recur in what patients?

Back 12

Those with open physes

Front 13

What two anatomic locations are most commonly affected?

Back 13

Proximal humerus
Proximal femur

Front 14

ln what two places are unicameral bone cysts (UBCs) generally found within bone?

Back 14

Central (compare with ABC: eccentric)
Metaphyseal (compare with giant cell tumor [GCT]: epiphyseal)

Front 15

What are the two histologic features?

Back 15

Clear, fluid-filled cyst lined by thin membrane of fibrous tissue
May see some multinucleated giant cells

Front 16

What are the two components of first-line treatment?

Back 16

Aspiration
Steroid injection

Front 17

What is the treatment of a recurrent lesion or an impending fracture?

Back 17

Curettage and bone graft

Front 18

ln lower extremities, consider what treatment for impending pathologic fracture?

Back 18

ORIF

Front 19

Is EG benign or maligant?

Back 19

Benign

Front 20

What are the two plain radiographic features?

Back 20

Destructive (lytic) lesion with distinct margins
Generally, no associated soft tissue mass

Front 21

How does an involved vertebral body classically appear?

Back 21

Vertebra plana (uniformly collapsed)

Front 22

What are the four key histologic features?

Back 22

Eosinophils
Cigar-shaped nuclei
Pale histiocytes
Birbeck granules (racquet-shaped inclusion bodies in cytoplasm on electron microscopy)

Front 23

Is histiocytosis generally a self-limited condition?

Back 23

Yes

Front 24

What are two local treatment options?

Back 24

Observation
Curettage and bone graft

Front 25

What are the different types of EG?

Back 25

Single-bone disease (most common,approximately 80%)
Multiple-bone disease
Bone disease with systemic and visceral involvement

Front 26

What are two systemic diseases?

Back 26

Hand-SchUller-Christian disease
Letterer-Siwe disease

Front 27

What are the three features of Hand-Schuller-Christian syndrome?

Back 27

Exophthalmos
Diabetes insipidus
Lytic skull lesions

Front 28

What age group is affected by Letterer-Siwe disease?

Back 28

Children <3 years old

Front 29

What are the four features of Letterer-Siwe?

Back 29

Multiple bony lesions
Anemia
Bacterial infections
Hepatosplenomegaly

Front 30

What is the prognosis?

Back 30

Fatal

Front 31

ls giant cell tumor benign or malignant?

Back 31

Benign but can be locally aggressive

Front 32

What gender is more commonly affected?

Back 32

Female (1.5:1)

Front 33

What are the three most common anatomic locations involved?

Back 33

Knee
Spine/sacrum
Distal radius

Front 34

What is the typical location within bone?

Back 34

Epiphysis

Front 35

Are physes generally open or closed?

Back 35

Physes are generally closed

Front 36

Contrast with physeal status in what other disorder?

Back 36

Chondroblastoma: physes are generally open

Front 37

Giant cell tumors may degenerate into what lesions?

Back 37

Aneurysmal bone cyst
Other neoplasms

Front 38

What is the appearance of giant cell tumor on bone scan?

Back 38

Doughnut: intense circumference,central lytic area

Front 39

ln what two ways are giant cell tumors treated?

Back 39

Curettage and bone grafting or polymethylmethacrylate (PMMA) with adjuvant (eg., phenol, cautery): 25% recur Marginal resection if multiply
recurrent or extensive bony
destruction

Front 40

What is the likelihood of developing metastases?

Back 40

3% incidence of benign pulmonary metastases

Front 41

What two anatomic locations are most commonly involved?

Back 41

Hands/feet
Jaw

Front 42

What is the typical radiographic appearance?

Back 42

Lytic, eccentric

Front 43

Histologically, giant cell reparative granuloma may resemble what? There a difference?

Back 43

Giant cell tumor
Bone is present

Front 44

What population is most commonly affected by myositis ossificans (MO)?

Back 44

Athletes

Front 45

Where is the ossihcation generally seen radiographically?

Back 45

The ossification is generally periosteally based

Front 46

What are the histologic features of the periphery and the center?

Back 46

Periphery: mature (eggshell)
Center: immature

Front 47

How is MO treated?

Back 47

Initial immobilization as Nonsteroidal antiinflammatoiy drugs ,
(NSAIDs)

Front 48

How and when should mobilization be resumed?

Back 48

Begin active range of motion after 2 days
Avoid passive stretching

Front 49

What is MO progressiva?

Back 49

Autosomal dominant disorder with multiple sites of ossitication

Front 50

What is the etiology of these lesions?

Back 50

Posttraumatic
Arise from subperiosteal hemorrhage

Front 51

What diagnosis comes to mind if the lesion resembles callus?

Back 51

Florid reactive periostitis

Front 52

What diagnosis comes to mind if the lesion resembles osteochondroma with cartilage cap?

Back 52

Bizarre parosteal osteochondromatous proliferation (BPOP)

Front 53

What diagnosis comes to mind if the lesion is found under the nail?

Back 53

Subungual exostosis

Front 54

What patient population is particularly at risk?

Back 54

African descent

Front 55

What are the most common anatomic locations of tumoral calcinosis?

Back 55

Extensor surfaces

Front 56

In affected patients, what is the usual serum calcium concentration?

Back 56

Normal

Front 57

What is the histologic appearance?

Back 57

Hydroxyapatite crystals