Kenneth Buckwalter, M.D.

Indiana University

kbuckwal@iupui.edu

(317) 274-1837

Radiology of Bone Tumors

Outline

• Work-up and Radiologic assessment

• Approach

– Normal bone anatomy

– Radiographic Analysis

• Location

• Margins

• Periosteal reaction

• Matrix

• Examples

Work-up

• History

– Age is critical.

– Smoker?

– Malignancy?

• Physical examination

– Breast mass?

• Good radiographs of affected region

– 2 views minimum

Multiple vs. Solitary

• Multiple

– metastatic

– congenital

• fibrous dysplasia

– acquired

• Paget

• Solitary

– metastatic

– primary bone tumor, malignant or benign

Multiple

• 50+ y/o

– known malignancy?

– myeloma, get SPEP

– otherwise, do metastatic work-up

• child to early adult

– known malignancy?

– EG?

– polyostotic fibrous dysplasia?

– otherwise, do metastatic work-up

Solitary

• Aggressive radiographic appearance

– bone scan to stage and verify solitary nature

– metastatic work-up

• baseline CXR

• spiral CT for pulmonary nodules

• Staging for surgery

– cross-sectional imaging: CT or MR

• Need tissue biopsy

Biopsy

• obvious superficial mass, blind biopsy

• tissue compartments must not be contaminated

– Biopsy should be done in consultation with a tumor surgeon.

• skinny needle most helpful with metastatic disease

• core best for primary tumor

Cross-sectional imaging

• Pictures are pretty, but diagnosis established

at histology

• MRI best for most tumors

– optimal results at sites with experience

• Role of CT limited

– may assist in assessing tumor matrix

– useful in directing biopsy

Normal Anatomy

epiphysis

metaphysis diaphysis

physis

childhood adult

cortex

medullary

space

physeal scar

How are Bone Tumors

Like Real Estate?

Location!

Location!

Location!

Location

• Location and age of patient most important

parameters in classifying a primary bone

tumor.

• Simple to determine from plain radiographs.

Location

Rad Clin N Am,

Dec 1981

Reaction of bone to tumor

• Limited responses of bone

destruction: lysis (lucency)

reaction: sclerosis

remodeling: periosteal reaction

• Rate of growth determines bone response

– slow progression, sclerosis prevails

– rapid progression, destruction prevails

Reaction of bone to tumor

• Margin between tumor and native bone is

visible on the plain radiograph.

• Slowly progressive process is “walled-off” by

native bone, producing distinct margins.

• Rapidly progressive process destroys bone,

producing indistinct margins.

Radiographic Margins

• Margin types 1A, 1B, 1C, 2, and 3

– least aggressive 1A, to most aggressive 3

• Aggressive lesions destroy bone.

• Aggressiveness increases likelihood of

malignancy.

– BUT, not all aggressive processes are malignant.

– AND, not all malignant diseases are aggressive.

Margins: 1A,1B,1C

increasing aggressiveness Rad Clin N Am,

Dec 1981

1A: sclerotic margin

• simple cyst (UBC)

• enchondroma

• FD / FX

• chondroblastoma

• GCT

• chondrosarcoma (rare)

• MFH (rare)

Rad Clin N Am,

Dec 1981

1B: well-defined, non-sclerotic

• GCT

• enchondroma

• chondroblastoma

• myeloma, metastatsis

• CMF

• FD

• chondrosarcoma

• MFH

Rad Clin N Am,

Dec 1981

1C: lytic, ill-defined margins

• chondrosarcoma

• MFH

• osteosarcoma

• GCT

• metastasis

• infection

• EG

• lymphoma

Rad Clin N Am,

Dec 1981

2: “motheaten”

• myeloma, metastases

• infection

• EG

• osteosarcoma

• chondrosarcoma

• lymphoma

Rad Clin N Am,

Dec 1981

3: “permeative”

• Ewing

• EG

• infection

• myeloma, metastasis

• lymphoma

• osteosarcoma

Rad Clin N Am,

Dec 1981

Types of

Periosteal

Reaction

Rad Clin N Am,

Dec 1981

Periosteal Reaction

• Limited usefulness

• Thick, uninterrupted

– long standing process, often non-aggressive

• stress fracture

• chronic infection

• osteoid osteoma

• Spiculated, lamellated

– aggressive process

– tumor likely

Codman Triangle

periosteal reaction

tumor

advancing tumor margin

destroys periosteal new

bone before it ossifies

Codman

Triangle

Tumor Matrix

• “Matrix” is the internal tissue of the tumor

• Most tumor matrix is soft tissue in nature.

– Radiolucent (lytic) on x-ray

• Cartilage matrix

– calcified rings, arcs, dots (stippled)

– enchondroma, chondroblastoma, chondrosarcoma

• Ossific matrix

– osteosarcoma

Matrix

Rad Clin N Am,

Dec 1981

Examples

AGE 13

Location metadiaphysis

Margins 1A-1B

Periosteal Reaction none

Matrix none

Other trabecular struts

DX UBC

Example 1

Example 2

AGE adult

Location metaphysis

Margins 1B

Periosteal Reaction none

Matrix none

Other fx

DX ABC

Example 2

Example 3: 13 y/o with knee pain

AGE 13

Location epiphyseal

Margins 1B

Periosteal Reaction none

Matrix none

Other

DX chondroblastoma

Example 3

Example 4: 45 y/o with knee pain

Example 4

AGE 45

Location metaphysis

Margins 1B

Periosteal Reaction none

Matrix none

Other epi involvement

DX GCT

Example 4*, 35 y/o F, GCT

AGE 66

Location diaphyseal

Margins 1A

Periosteal Reaction minimal, thick

Matrix none

Other 2nd lesion

DX wait…..

Example 5

Example 5

AGE 66

Location diaphyseal

Margins 2

Periosteal Reaction none

Matrix none

Other

DX wait…..

Example 5

AGE 66

Location flat bone

Margins 1B

Periosteal Reaction none

Matrix none

Other multiple

DX myeloma

Example 6: 14 y/o with claudication

Example 6

Example 6

AGE 14

Location metaphysis

Margins 1B

Periosteal Reaction none

Matrix mature bone

Other claudicat'n

DX exostosis

Example 7: 25 y/o woman with knee pain

Example 7

AGE 25

Location metaphysis

Margins 1A

Periosteal Reaction none

Matrix ?

Other multiple

DX NOF

Example 7

Example 8: 45 y/o with thigh pain

Example 8

AGE 45

Location diaphysis

Margins 1B

Periosteal Reaction thick

Matrix faint

Other

DX osteoid osteoma

AGE 12

Location diaphysis

Margins 3

Periosteal Reaction lamellated

Matrix none

Other

DX Ewing

Example 9

Example 9

“onion-skin”

Example 10

AGE 16

Location diaphysis

Margins 3

Periosteal Reaction spiculated

Matrix bone

Other fx

DX osteosarcoma

Example 10

AGE 20

Location metaphysis

Margins 3

Periosteal Reaction irregular

Matrix bone

Other

DX osteosarcoma

Example 10*, osteosarcoma

AGE 56

Location metaphyseal

Margins 1A

Periosteal Reaction none

Matrix chondroid

Other

DX enchondroma

Example 11

Summary

• Radiographs are essential

• Aggressiveness of process dictates the

response of the bone

• Most helpful information in analysis

– Age

– Location

– Margins

“Don’t Touch Me”

• Fibrous lesions

– fibrous dysplasia

– NOF (non-ossifying fibroma)

• enchondroma

• exostosis

• unicameral (simple) bone cyst

AGE

Location

Margins

Periosteal Reaction

Matrix

Other

DX

Example