422 - 423 - Primary Bone Tumors

Question 1

What are 2 benign bone tumors?

Answer 1

1. Giant cell tumor

2. Osteochondroma (exostosis)

Question 2

Patients in what age range get giant cell tumors?

Answer 2

20 - 40 years old

Question 3

In what part of the bone do giant cell tumors typically arise?

Answer 3

epiphyseal end of long bones (especially distal femor or proximal tibia, i.e. near the knee)

Question 4

A locally aggressive benign tumor that often occurs around the knee:

Answer 4

giant cell tumor

Question 5

How do giant cell tumors appear on x-ray?

Answer 5

soap bubble appearance

Question 6

How do giant cell tumors appear on histology?

Answer 6

multinucleated giant cells

Question 7

What is the most common benign tumor of the bone?

Answer 7

osteochondroma

Question 8

What demographic does osteochondroma affect?

Answer 8

Males < 25 years old

Question 9

What would you see on histology of an osteochondroma?

Answer 9

Mature bone with a cartilaginous cap

Question 10

Does osteochondroma transfrom to chondrosarcoma?

Answer 10

Rarely

Question 11

What are 3 examples of malignant bone tumors?

Answer 11

1. Osteosarcoma (osteogenic sarcoma)
2. Ewing sarcoma
3. Chondrosarcoma

Question 12

After multiple myeloma, what is the second most common primary malignant bone tumor?

Answer 12

osteosarcoma

Question 13

What age demographic does osteosarcoma affect?

Answer 13

Bimodal distribution: 10-20 y.o. (primary) and > 65 y.o. (secondary)

Question 14

What are 5 predisposing factors of osteosarcoma?

Answer 14

1. Paget disease of the bone
2. Bone infarcts
3. Radiation
4. Familial retinoblastoma,
5. Li-Fraumeni syndrome (germline P53 mutation)

Question 15

What part of the bone is affected by osteosarcoma?

Answer 15

Metaphysis of long bones, often around the knee

Question 16

How do osteosarcomas appear on x-ray?

Answer 16

Codman triangle or sunburst pattern

Question 17

What creates the Codman triangle pattern on x-ray of an osteosarcoma?

Answer 17

elevation of the periosteum

Question 18

Are osteosarcomas slow growing or aggressive?

Answer 18

aggressive

Question 19

How do you treat osteosarcoma?

Answer 19

Surgical en bloc resection (with limb salvage) and chemotherapy

Question 20

Who gets Ewing sarcomas?

Answer 20

Boys < 15 years old

Question 21

Where does Ewing sarcoma appear in the body?

Answer 21

diaphysis of long bones, pelvis, scapula, and ribs

Question 22

How do Ewing sarcomas appear on histology?

Answer 22

Anaplastic small blue cells (that arise from neuroectoderm)

Question 23

What is the course of Ewing sarcoma?

Answer 23

Extremely aggressive with early metastases, but responsive to chemotherapy

Question 24

Which tumor is associated with an onion skin appearance of the bone?

Answer 24

Ewing sarcoma

Question 25

What is the translocation in Ewing sarcoma?

Answer 25

t(11;22)

11 + 22 = 33 (Patrick Ewing’s jersey number)

Question 26

Who gets chondrosarcomas?

Answer 26

Men 30-60 years old

Question 27

Where do chondrosarcomas appear?

Answer 27

Usually in the pelvis, spine, scapula, humerus, tibia, or femur

Question 28

Are chondrosarcomas common?

Answer 28

No, rare

Question 29

What are 2 ways chondrosarcomas can arise?

Answer 29

1. Primary

2. Transformation of osteochondroma

Question 30

What do chondrosarcomas look like grossly?

Answer 30

expansile glistening mass within the medullary cavity

Question 31

What is an exostosis? What kind of bone tumor is associated with exostosis?

Answer 31

Projection of new bone out of the surface of a bone (continuous with bone marrow), associated with osteochondroma (arises as a lateral projection of the growth plate)

Question 32

What is an osteoid osteoma? Where does it arise? (pathoma)

Answer 32

A benign tumor of osteoblasts surrounded by a rim of reactive bone; cortex of long bone (diaphysis)

Question 33

Who gets osteoid osteomas?

Answer 33

Adults <25 y.o.

Question 34

What does an x-ray of osteoid osteoma show?

Answer 34

Bony mass with radiolucent (osteoid) core

Question 35

What is an osteoma? What disease are they associated with?

Answer 35

A benign bone tumor that usually occurs in the skull. They commonly arise in the surface of facial bones in patients with Gardner syndrome

Question 36

Where do chondromas typically arise?

Answer 36

in the medulla of small bones of hands and feet

Question 37

Are primary or metastatic tumors in the bone more common?

Answer 37

metastatic