General

Question 1

Pluripotent Mesenchymal Cells Form ?

Answer 1

Bone
Cartilage
Fibrous Tissue
Lipogenic Tissue
Blood Vessels
Nervous Tissue
Small Round Blue Cells

Question 2

Tumor Classification Based On (3) ?

Answer 2

Predominant Tissue Type
Benign vs Malignant
Matrix vs Non-Matrix Producing

Question 3

BENIGN BONE-FORMING Tumors (3) ?

Answer 3

Osteoma
Osteoid Osteoma
Osteoblastoma

[enostosis]

Question 4

MALIGNANT BONE-FORMING Tumors (3) ?

Answer 4

OSTEOSARCOMA

1. Intramedullary **most common
2. Surface (Juxtacortical)
3. Intracortical ** extremely rare

Question 5

Intramedullary OSTEOSARCOMA (3) ?

Answer 5

Conventional **most common (80-85%)
Telangiectatic
Low grade intra-osseous

Question 6

Most common sites of INTRAMEDULLARY OSTEOSARCOMAs ?

Answer 6

Distal femur > Proximal tibia > Proximal humerus

Children between 10 and 20 yo

Question 7

Types of Tissue Assoc with :
Conventional
Parosteal
Periosteal

Answer 7

Conventional - Spindle Cell
Parosteal - Fibroblastic
Periosteal - Cartilage
High grade surface - same as conventional but ON SURFACE vs intramedullary

Question 8

Juxtacortical OSTEOSARCOMA

Answer 8

Parosteal ** low grade
Periosteal
High grade surface

Question 9

How are OSTEOSARCOMAs TREATED ?

Tumor-type exceptions (2) ?

Answer 9

Neoadjuvant chemotherapy
Surgery
Post-op chemotherapy

Exceptions; SURGERY ALONE for:
Low grade intra-osseous
Parosteal

Question 10

BENIGN CARTILAGE-FORMING Tumors (5) ?

Answer 10

Enchondroma
Osteochondroma ** surface of bone
Chondroblastoma **solely on epiphysis of bone
Chondromyxofibroma **rare
Periosteal Chondroma **rare

Question 11

MALIGNANT CARTILAGE-FORMING Tumors (5) ?

Answer 11

CHONDROSARCOMA

1. Conventional (Grades I, II, III)
2. Dedifferentiated
3. Clear Cell **solely on epiphysis of bone
4. Mesenchymal ** 2/3s bone; 1/3 soft tissue
5. Periosteal Chondrosarcoma **surface

Occur in adults > 50 yo

Question 12

Which benign Cartilage-Forming act like BENIGN-AGGRESSIVE (2) ?

Answer 12

Chondroblastoma **solely on epiphysis of bone
Chondromyxofibroma

Biological activity - grow and destroy bone BUT do not metastasize

Question 13

What is a Dedifferentiated Chondrosarcoma?

Associated high grade tumor types (3) ?

Answer 13

Low grade tumor adjacent to high grade spindle cell
Typically low grade transforms into high grade over time

3 type of associated Spindle Cell Types:

1. Osteosarcoma
2. Undifferentiated Pleiomorphic Sarcoma (MFH)
3. Fibrosarcoma

Question 14

Tumor types solely on epiphysis (2) ?

Answer 14

Chondromablastoma

Clear Cell Chondrosarcoma

Question 15

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Answer 15

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Question 16

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Answer 16

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Question 17

BENIGN FIBRO-OSSEOUS Tumors (6) ?

Answer 17

Non-Ossifying Fibroma
Fibrous Cortical Defect
Benign Fibrous Histiocytoma
Fibrous Dysplasia
Osteofibrous Dysplasoia
Desmoplastic Fibroma

Question 18

MALIGNANT FIBRO-OSSEOUS Tumors (6) ?

Answer 18

FIBROSARCOMA

Undifferentiated Pleiomorphic Sarcoma (MFH)