Bone Tumors

Question 1

Location! Location! Location! 2 + 2 and their properties

Answer 1

Prognosis: anatomically resectable limbs versus poor local control - spine and pelvis

Diaphysis + Metaphysis - Osteosarcoma and Ewing Sarcoma - more for young children and adults, only ones responsive to chemotherapy

Epiphysis - Chondroblastoma, Giant Cell Tumour - CBTM is more for elderly

Question 2

Osteosarcoma

Answer 2

AKA osteogenic sarcoma, from mesenchyme w osteoblastic differentiation and producing malignant Osteoid

Bone-forming tumor; Most common; Malignant

Periosteum gets lifted; Sunburst pattern on X ray; tumor spicules of calcified bone radiating in right angles

Typically: Metaphysis of long bones, necrosis, hemorrhage; @ metaphyseal growth plates

Question 3

EWS

Answer 3

A family of tumour, 2nd most common for kids

Ewing Sarcoma - small, round, uniform cell
No osteoid formation

Ewing Sarcoma under category of Small Round Blue Cell Tumor - which Wilms’ Tumor blastema component is also part of - w small round cells;
- also Small Cell Lung Carcinoma - w the PNsyndrome

Question 4

Chondrosarcoma

Answer 4

Malignant; Cancer cells which produces cartilaginous matrix not osteoid
Not chemo sensitive

Chondroblastoma is benign;

Question 5

2 properties of malignant primary bone tumors

Answer 5

Permeation of bone trabeculae, marrow

Soft tissue, adjacent organ invasion

Question 6

Giant Cell Tumour of Bone

• property
• Dx

Answer 6

Mostly benign
Presence of MGC - multinucleated giant cells - osteoclast-like cells

Dx: other bone stuff w MGCs as well including Brown Tumor, found in Oestitis Fibrosa Cystica - oestoclast activity in HyperPTH