Bone tumors

Question 1

Benign bone tumor characteristics

Answer 1

Slow growing,
Well defined SCLEROTIC margin, called Geographic lesions.
Or, lack a sclerotic rim but still have a clear border between the tumor and the bone.

Benign lesions do not usually disrupt normal bone architecture.

Question 2

Malignant lesions

Answer 2

Poorly defined border/multiple lesions
“moth-eaten” bone appearance. Also called a “permative” type lesion. Indicates the tumor is growing too fast for reactive bone growth to form around it.
Lesions disrupt bone architeture.

May invade through the cortex and through the periosteum into soft tissue.

Codmans triangle, The growing tumor lifts the periostium away from the bone, creating a triangle shaped lesion. Seen in osteosarcoma, Ewings sarcoma

Onion skin periosteal growth.

Question 3

What type of metastatic bone lesion is osteoBLASTIC

Answer 3

Breast cancer and Hodkins lymphoma mets

sometime present as blastic (increased density) lesions.

Question 4

Types of bone tumor by age

Answer 4

1-10 years Ewings sarcoma, Osteosarcoma.

10-30 years Osteosarcoma or Ewings sarcoma

30-40 Fibrosarcoma, Osteosarcoma, Giant cell tumor, Lymphoma

> 40 Metastases, Multiple Myeloma, Chondrosarcoma

Question 5

Cartilaginous matrix produced by tumors looks like

Answer 5

Small punctate or swirled calcified areas

Question 6

Osseous matrix produced by tumors looks like

Answer 6

Dense confluent bone calcification.

Question 7

Osteosarcoma and Ewing sarcoma characteristicsq

Answer 7

lytic, permeative, moth-eaten lesions of the bone.

Typically in long bones. Onion skin/Codman triangle periosteal reaction

Question 8

Chondroblastoma

Answer 8

Spotty matrix calcifications within a lytic expansive lesion.

a rare, benign bone lesion.

Question 9

Plasmacytoma/Multiple Myeloma

Answer 9

Malignant plasma cell tumor.

More often presents as a primary solitary plasmacytoma within bone, and less commonly as a the dessiminated neoplasm with multiple bone loci.

Diagnosed by immunoglobulin electrophoresis, bone marrow biopsy, and CT scan to locate the lesions.

X-ray can also show the lucent lesions

MR is also sensitive at the bone marrow inolvement, T1 and STIR images.

Question 10

Fibrous dysplasia

Answer 10

Bony enlargement of the medullary space due to excessive fibroblast proliferation/fibrosis of the space.