Volume 3

Osteosarcoma Variants

Hemorrhagic osteosarcoma------------Case 110 & 499-503

Parosteal osteosarcoma-----------------Case111 & 504-510

Periosteal osteosarcoma----------------Case 112 & 511-517

Pagetic sarcoma-------------------------Case 113 & 518-528

Low grade intramedullary OGS------Case 114 & 528.1-530

Radiation induced OGS---------------Case 115 & 531-537

Multicentric osteosarcoma------------Case 116 & 538-542

Soft tissue osteosarcoma--------------Case 118 & 543-545

Intracortical osteosarcoma------------Case 119 & 546-547

Osteogenic

Sarcoma

Variants

Hemorrhagic

Osteogenic

Sarcoma

Hemorrhagic (Telangiectatic) Osteosarcoma

The hemorrhagic (OGS), an extremely lytic and hemorrhagic

variant of the osteosarcoma, presents in the same age group and

location as a classic osteosarcoma but has a radiographic

appearance almost identical to that of an aggressive aneurysmal

bone cyst, making for a very difficult differential consideration

for the radiologist. At the time of biopsy the tumor is very

hemorrhagic and has the gross appearance of an aneurysmal

bone cyst. Even microscopically, many areas of the hemorrhagic

OGS will have the appearance of an aneurysmal bone cyst with

only an occasional mitotic figure. For this reason, it is very

important for the surgeon who performs the biopsy to obtain

an adequate specimen with good sampling by means of an open

biopsy as apposed to a simple needle biopsy. The microscopic

features of the hemorrhagic OGS is a large number of benign-

appearing giant cells and thus the terminology “giant cell rich”

osteosarcoma that is used by many pathologists. There is very

little evidence of osteoblastic acitivity in the hemorrhagic OGS

and, because it is so lytic in character, it frequently presents with

a pathologic fracture early in the course of the disease and with that

come potential problems for the treating orthopedic surgeon who

must deal with the major contamination that occurs during the

fracture. Because of the possible complications, one might consider

an early limb salvage procedure before the fracture occurs.

It was once felt that the prognosis for the hemorrhagic OGS

was worse than that of the classic OGS because of its lytic dest-

uctive nature. However, since the advent of systemic chemotherapy,

the prognosis for survival is no different than for a classic OGS.

CLASSIC

Case #110

23 year male

hemorrhagic OGS

proximal humerus

Aneurysmal lesion

Coronal T-1 MRI

hemorrhagic

tumor

Coronal T-1 MRI

thru path fracture

tumor

Resected tumor cut in path lab

Photomic showing giant cells and malignant cells

Photomic showing hemorrhagic response

blood

osteoid

Post op x-ray with

alloprosthetic

reconstruction

Neer

allograft

18 year followup x-rays

Case #499

15 year male

hemorrhagic OGS

distal femur

Lateral view

Bone scan

Sagittal T-2 MRI

tumor

hemorrhagic

tumor

Coronal T-2 MRI

Axial T- 2 MRI

tumor

Photomic

blood

3 yrs post op Compress

total knee reconstruction

CPS

osseo-

integration

Case #500

19 year male

hemorrhage OGS

proximal femur

Looks like ABC

Lateral view

Initial biopsy reveals aneurysmal bone cyst

6 weeks later

shows lysis of

outer shell

Repeat biopsy

reveals

hemorrhagic OGS

Hip disarticulation specimen

tumor

femoral

head

2nd biopsy Photomic

Case #501

6 year female

path fracture thru

unicameral bone cyst

Lateral view

cystic

lesion

7 weeks after

steroid injection

cyst

1 month later and

progressive lytic

destruction

Biopsy here shows hemorrhagic OGS

Case #501.1

19 year old male with

acute onset of pain 2 wks

ago in right hip

Telangiectatic OGS

PO 1 mo

2 mo 3 mo

Cor T-1 T-2

Axial T-1 T-2

Gad

Sag T-2 Gad

Case #502

4 year male

looks like

unicameral bone cyst

cystic

lesion

Progressive lysis

after steroid injection

2 months later

with progressive

lysis and looking

malignant

Biopsy reveals hemorrhagic OGS

Clinical appearance before shoulder disarticulation

Case #503

17 year female

hemorrhagic OGS

C-3

AP view

CT scan

Photomic

6 years later with

spontaneous fusion

and no tumor

Parosteal

Ostogenic

Sarcoma

Parosteal Osteosarcoma

The parosteal (OGS) is a low grade variant arising from the surface

of a long bone that presents as an exophytic mass with dense fibro-

osseous tissue. It carries an excellent five year survival prognosis

of 85% and accounts for about 4% of all osteosarcomas. This

tumor has very little, if any, medullary involvement which clearly

separates it from the classic OGS. It is seen more commonly in

females than males and is found in a slightly older age group

than the classic OGS. By far the most common location for this

tumor is in the posterior aspect of the distal femur where it is

frequently presents with minimal symptoms of pain but with a

palpable tumor mass that might have been present many years

before medical advise was sought. Histologically, this tumor has a

very low mitotic index and in many cases can be confused with

a normal healing fracture callous with occasional areas of cartilage

being seen. Because this tumor is extremely low grade, it is not

responsive to adjuvant therapy such as chemotherapy or

radiation therapy. The treatment consists of a wide surgical

resection that must have safe margins, otherwise the recurrence

rate will be quite high. Recurrence can occur 10 to 15 years after

the surgery. In many cases the lesion can be resected without

sacrificing the adjacent joint, but in larger lesions the best

approach is a total joint replacement similar to that used for the

classic OGS.

CLASSIC

Case #111

32 year male

parosteal OGS

distal femur

AP view

Bone scan

Sagittal T-1 MRI

Sagittal STIR MRI

tumor

Axial T-1 MRI

Axial STIR MRI

tumor

Photomic

Higher power

Case #504

18 year male

parosteal OGS

distal femur

AP view

tumor

Bone scan

Axial T-2 MRI

tumor

Sagittal T-2 MRI

tumor

Macro section

tumor

Photomic

Compress total knee reconstruction 2 years later

osseointegration

10 years later with

recurrence as a high

grade dedifferentiated

parosteal OGS tumor

Another view

tumor

Photomic of recurrence

Close up of

osseointegration of

Compress implant

Case #505

32 year male

parosteal OGS

proximal humerus

tumor

Axillary view

tumor

CT scan

tumor

Amputation specimen cut in path lab

Photomic

Case #506

25 year male

parosteal OGS

distal femur

Distal femoral

resection specimen

tumor

Cut specimen

in path lab

tumor

fatty

marrow

Case #507

13 year male

parosteal OGS

mid femur

AP view

Lateral view

CT scan

Segmental resection specimen

Autoclaved bone replaced with IM nail fixation

Post op x-ray

2 years later

autoclaved

bone

Case #508

17 year male with parosteal OGS mid tibia

Lateral x-ray

CT scan

tumor

Bone scan

Segmental resection

mid tibial lesion

biopsy

site

Surgical specimen cut in path lab

tumor

Allograft reconstruction over IM nail

X-ray 1 year later

Case #509

41 year female

parosteal OGS

humerus

CT scan

Resected cut specimen in path lab

tumor

Case #509.1

10/06 3/07

17 year male with football injury 9/06

Parosteal OGS pseudotumor M.O.

Sag T-1 Sag Gad

Axial T-1

Axial Gad

Case #510

32 year female with high grade parosteal OGS femur

Macro section

tumor

Photomic

Periosteal

Osteogenic

Sarcoma

Periosteal Osteosarcoma

The periosteal osteosarcoma is another surface type OGS that

tends to be low grade to intermediate with potential for pulmonary

metastasis in about 25% of cases. It accounts for 2% of all OGS’s

and, compared to the parosteal OGS, has a much higher percentage

of cartilagenous tissue in the tumor to the point where it can look

like a periosteal chondroma but with a much higher mitotic index.

One must find a few areas of osteoid formation to classify this as

a periosteal OGS. It is seen typically in the second decade of life

and is slightly more common in females than males. It arises from

long bones, typically the tibia or femur, and has a higher incidence

in diaphyseal bone than does OGS. Like the parosteal OGS, this

lesion is treated by aggressive wide local resection that often can

spare the adjacent joint. In most cases chemotherapy is not utilized

unless the clinical picture is more aggressive than usual.

CLASSIC Case #112

15 year female with periosteal OGS tibia

CT scan

Sagittal CT scan

tumor

Axial T-2 MRI

Photomic

Post op x-ray following

wide resection and

allograft reconstruction

Case #511

30 year male with periosteal OGS prox tibia

CT scan

Sagittal T-2 MRI

Axial T-1 MRI

tumor

edema

Wide resection

proximal tibia tumor

bulge

Cut specimen

in path lab

tumor

Photomic

Proximal tibia resected ready for reconstruction

Post op x-ray with

alloprosthetic

reconstruction

TKA

allograft

Case # 512

9 year female

periosteal OGS

tibia

AP x-ray

Lateral view

Cut specimen in

path lab following

AK amputation

Photomic

Higher power

Case #513

14 year male

periosteal OGS

Sagittal T-2 MRI

Axial T-1 MRI

Axial T-2 MRI

Case #514

26 year female

periosteal OGS

distal femur

Lateral view

X-ray 10 years

following wide

resection and cemented

prosthetic reconstruction

stress

shielding

Case #515

12 year female

periosteal OGS

tibia

Bone scan

Axial T-1 MRI

Photomic

Case #516

15 year male

periosteal OGS

distal tibia

CT scan

Bone scan

Photomic

Case #517

39 year female

periosteal OGS

pseudotumor

In fact is a Nora’s

lesion or

bizarre parosteal

osteochondromatous

proliferation (BPOP)

Bone scan

CT scan

Axial Gad contrast MRI

edema

Sagittal PD

Sagittal T-2 MRI

edema

Axial gad contrast MRI

Pagetic Sarcoma

Pagetic Sarcoma

There are multiple diseases of the skeletal system that can result

in a secondary form of OGS most likely brought about by a second

mutation at a later age in a patient with chronic benign disease.

These diseases include Paget’s disease, osteoblastoma, fibrous

dysplasia, benign giant cell tumor of bone, bone infarcts, and

chronic osteomyelitis. The most common of this group is Paget’s

disease, a non-specific inflammatory osteomyelitis of bone seen

in older patients that may be induced by a virus infection. Approx-

imately 1% of patients with Paget’s disease can go on to Pagetic

OGS which accounts for 3% of all OGS. The most common

location for this secondary form of OGS is in the humerus,

followed next by the pelvis and femur. The patients typically have a

long history of dull, aching pain from their inflammatory Paget’s

disease but then suddenly develop an acute new pain in the area of

the older pain with x-ray evidence of recent lysis and destruction

of old Pagetic reactive bone. The prognosis for survival in this

secondary form of OGS is extremely poor with only about 8%

surviving, mainly because the older age group in which the disease

occurs make it impractical to implement the aggressive protocols

used in younger age groups.

CLASSIC Case #113

80 year female with Pagetic sarcoma pelvis

tumor

Bone scan

Axial T-2 MRI

tumor

Photomic

osteoid

Post op internal hemipelvectomy

Case#518

83 year female

Pagetic sarcoma

pelvis

tumor

CT scan

tumor

Another CT cut

tumor

Photomic

Case #519

85 year female with Paget’s disease pelvis

Same disease in

lumbar spine

Same disease

in skull

Same disease in tibia

Advancing osteolytic wedge

Same patient with

Pagetic sarcoma

humerus

tumor

old Paget’s

new

Macro section

from amputation

specimen tumor

Photomic

Post op x-ray following forequarter amputation

Case # 520

73 year female

Pagetic sarcoma skull

ready for resection

Lateral view of skull

Occipital view

Tangential view

tumor

Resected specimen cut in path lab

Photomic

Case #521

82 year male

Pagetic sarcoma

distal humerus

old Paget’s

with prior

fracture

Close up of new tumor

tumor

Photomic

Case #522

80 year female

Pagetic sarcoma

distal humerus

Case #523

84 male with multi focal Pagetic sarcoma

femur

humerus

Case #524

83 year male

Pagetic sarcoma

femur

Case #525

60 year male

Pagetic sarcoma

femur

Lateral view

Photomic

Photomic

Case #526

78 female

Pagetic sarcoma

proximal tibia

Lateral view

tumor

Case #527

92 year male

Pagetic sarcoma tibia

Case #528

78 year female

Pagetic sarcoma

lumbar spine

Low Grade

Intramedullary

Osteogenic

Sarcoma

Low Grade Intramedullary OGS

Low grade intramedullary OGS is another rare low grade fibro-

osseous variant of OGS that is unique because it is totally confined

within the cortical anatomy of a long bone, most typically around

the knee joint. It is found in an older age group than the classic

OGS and is typically seen between the ages of 15 and 55 years;

it affects males and females equally. The radiologic picture is that

of a diffuse sclerotic change within the metaphysis of the long

bone with no periosteal response or lytic destruction of the cortical

anatomy. The smoky appearance of metaphyseal bone suggests

the diagnosis of chronic osteomyelitis or perhaps fibrous dysplasia.

Microscopically, the tumor has a histological appearance similar

to parosteal OGS and because of this carries the same excellent

prognosis for survival as we see in parosteal sarcoma. Likewise,

treatment is similar without the use of chemotherapy or radiation.

These lesions must be treated with complete wide resection that

frequently involves a TKA, similar as in the classic OGS.

CLASSIC

Case #114

63 year female

intramedullary OGS

distal femur

Lateral view

Bone scan

CT scan

tumor

Macro section from

resected specimen

tumor

Photomic

Photomic

Case #528.1

51 year female

low grade

intramedullary OGS

distal femur

tumor

Bone scan

Coronal T-1 MRI

tumor

Axial T-1 MRI

tumor

Resected distal femur cut in path lab

tumor

Photomic

Case #529

32 year female

low grade

intramedullary OGS

distal femur

tumor

Lateral view

CT scan

Photomic

Case #530

56 year male

low grade

intramedullary OGS

distal tibia

tumor

Lateral view tumor

Bone scan

Photomic

Radiation-induced

Osteogenic

Sarcoma

Radiation-induced Osteosarcoma

One of the most malignant forms of OGS is the secondary type

induced by radiation therapy, usually over 3000 rads, for some

type of either benign or malignant disease process in the past.

One of the most common types of radiation-induced OGS is

seen in patients with breast cancer who receive local radiation

following radical mastectomy and than develop OGS in the

shoulder girdle area. Other malignant diseases that can result in

OGS after radiation therapy include Ewing’s sarcoma and

lymphomas. Benign diseases that can result in OGS from

radiation therapy include GCT,ABC, and fibrous dysplasia. The

average delay for the occurrence of secondary OGS is 15 years,

with a range from 3 to 55 years. The prognosis for this variant is

extremely poor, similar to Pagetic OGS. It has a very high rate

of metastasis to the lung for which chemotherapy is not very

effective.

CLASSIC

Case #115

33 year female

radiation-induced

sarcoma scapula

Widely resected specimen cut in path lab

tumor

Close up

tumor

scapula

Photomic

Higher power

Post op x-ray following scapular wing resection

Case #531

35 year female with radiation sarcoma prox femur

tumor

prior radiation treatment for Hodgkin’s 20 yrs ago

Frog leg lateral

tumor

Shortly after with

pathologic fracture

Biopsy photomic

tumor

Higher power

Case #532

72 year male

radiation sarcoma pelvis

Prior radiation therapy

for prostate cancer

3 years before

Another view at a

different date with

hip dislocation

Photomic

Case #532.1

79 yr male with prior prostate CA radiation therapy

and now presents with radiation OGS

Radiation induced OGS

Coronal Anterior CT Posterior CT

L Sagittal CT scan R Sagittal CT scan

Low axial CT

cut thru L hip

showing large tumor

Upper CT cut thru

SI area showing

tumor R post ilium

Metastatic disease seen on chest x-ray

Case #533

56 year female with radiation sarcoma scapula

Prior history of radiation for breast cancer

Oblique view

Bone scan

Photomic

Case #534

63 year female with radiation sarcoma scapula

with prior radiation treatment for breast CA 12 yrs ago

tumor

Case #535

44 year female with

radiation sarcoma

proximal humerus 2nd

to prior radiation for

breast cancer tumor

Photomic with radiation OGS

Case #536

76 year male

radiation sarcoma

femur

Prior history of

radiation therapy

for soft tissue tumor

10 years ago

Bone scan

Photomic radiation OGS

Case #537

Elderly M.D. with long

history working under

X-ray fluoroscope

Now skin cancer and

radiation sarcoma

index finger

X-ray of index

finger sarcoma

tumor

Photomic radiation sarcoma

Multicentric

Osteogenic

Sarcoma

Multicentric Osteosarcoma

The multicentric variant of OGS is an extremely rare variant

occurring in approximately 1% of all OGS. It has two distinct

categories: (1) Synchronous multicentric OGS occurring in child-

hood and adolescence. This is the more severe variant, considered

to be extremely high grade with a very poor prognosis associated

with it. This form presents with multiple sclerotic lesions seen in a

fairly symmetrical fashion in long bones, mostly in the lower

extremities and because of the heavy tumor burden associated

with multiple lesions throughout the skeleton, the alkaline phos-

phatase is frequently elevated. (2) Metachronous multicentric OGS

occurring mainly in adults is less aggressive than the synchronous

form seen in children, presenting usually with a solitary lesion.

Then, later on, more lesions develop that are considered multi-

focal in nature. The possibility of metastasis can not be ruled out.

These forms of OGS are quite resistant to chemotherapy and

surgical treatment is frustrating because of the multi focal disease.

CLASSIC

Case #116

8 year female

multicentric OGS

Close up distal femur

Lateral view

Bone scan

Close up

bone scan

Upper body

bone scan

Coronal T-1 MRI

Another coronal cut

T-1 MRI

Sagittal T-1 MRI

Photomic

Another photomic

Case #538

18 year female

multicentric OGS

pelvis and femur

Gad contrast coronal MRI

tumor

tumor

Another Gad contrast cut

Axial T-2 MRI

pelvic

tumor

Recon plate placed across pelvic ring surgical defect

Internal Hemipelvectomy

Placement of air screws just prior to cementation

Placement of cement around screws and plate

cement

Constrained total hip in and securing muscles

to custom proximal femoral replacement implant

total

hip

femoral implant

Outer face of resected specimen

acetabulum

ilium

tumor

bulge

Inner face

tumor

bulge

ilium

Closure

Post op x-ray

recon plate

and screws

Case #539

16 year female

multicentric OGS tumor

Proximal tibial lesion

Lateral view with

skip lesion in

distal tibia

Bone scan showing two lesions in tibia

Bone scan showing

iliac lesion

Bone scan showing

sternal lesion

Photomic from tibial biopsy

Proximal tibial

resection and

total knee

reconstruction

tumor

bulge

Proximal tibial

prosthesis in position

ready for relocation

and closure

Reconstruction

completed and

ready for closure

Case #540

Multicentric OGS

femur and sacrum

20 year male

Lateral view

Coronal T-1 MRI

showing tumor at

both ends of femur

Sagittal T-1 MRI

distal femur

tumor

Axial T-2 MRI distal femur

tumor

Another axial T-2 MRI

Bone scan

Coronal T-1 MRI

Axial T-1 MRI

Coronal gad contrast MRI showing sacral lesion

tumor

Photomic from femoral biopsy

Case #541

10 year female with multicentric OGS femur and tibia

Lateral view

tumor

tumor

skip

lesion

AP view femur

Coronal T-2 MRI

distal femur

tumor

Sagittal T-2 MRI

distal femur

tumor

tibial

lesions

Coronal T-1 MRI

knee joint

tumor

tumor

Coronal T-1 MRI showing multicentric involvement

tumor

Case #542

15 year male with multicentric OGS tibia and femur

tumor

Coronal T-1 MRI

tumor

tumor

Coronal T-2 MRI

tumor

Sagittal T-1 MRI

tumor

Axial T-2 MRI view of distal femur

tumor

Soft Tissue

Osteogenic

Sarcoma

Soft Tissue Osteosarcoma

OGS can be seen in soft tissue outside the skeletal system. It

accounts for 4% of all OGS and is typically in large muscle groups

around the pelvis and thigh area. It occurs most often in patients

over 40 years of age and hits males and females equally. Soft

tissue OGS, with its mature appearing bone in the central area of

the lesion and aggressive, poorly mineralized tissue at the

periphery, must be differentiated from myositis ossificans, which

has a typical zonal pattern with peripheral maturation of bone

formation. As with any soft tissue sarcoma, the treatment consists

of wide local resection. Because of the poor prognosis, worse

than that of bone osteosarcoma, systemic chemotherapy is utilized

extensively as one would use for a typical medullary OGS.

CLASSIC

Case #118

67 year male

soft tissue OGS

calf

tumor

AP view

Sagittal T-1 MRI

tumor

Axial T-1 MRI

Cut surgical specimen in path lab

Photomic

Case #543

76 year female

soft tissue OGS

calf

Lateral view

CT scan

Bone scan

Axial T-1 MRI

Sagittal T-1 MRI

tumor

Photomic

Case #544

60 year female with

soft tissue OGS leg

Oblique view

Bone scan

Case #545

63 year male

soft tissue OGS

hand tumor

Lateral view

Axial T-1 MRI

tumor

Axial T-2 MRI

tumor

Coronal T-2 MRI

tumor

Multiple pulmonary mets

Intracortical

Osteogenic

Sarcoma

Intracortical Osteosarcoma

The intracortical OGS is perhaps the rarest variant of OGS with

only 14 cases described in the world literature since 1960. It

occurs between the ages of 10 and 47 years, equally between

males and females, and is seen most typically in the femur or

tibia as a metadiaphyseal lesion with a radiographic appearance

very similar to that of osteoid oasteoma. The prognosis is usually

quite good with a total of three deaths in the world literature. It

is usually treated by wide resection without chemotherapy. A

few cases are higher grade and carry a poor prognosis similar

to the classic OGS.

CLASSIC Case #119

42 year female with intracortical OGS femur

Bone scan

Axial PD MRI

Sagittal T-2 MRI

Early biopsy photomic

X-ray 18 months

after curettement

with recurrence

Bone scan at time of recurrence

Axial Gad contrast MRI same time

Sagittal PD MRI

same time

tumor

Unicortical segmental wide resection

tumor

Photomic of resected specimen

Post op x-ray following

unicortical resection

and allograft recon

allograft

Sagittal PD & T-2 MRI 18 months later with met to C-spine

tumor

PD T-2

Case #546

43 year female

intracortical OGS

distal femur

Lateral view

Sagittal T-1 MRI

Sagittal T-2 MRI

tumor

Biopsy photomic

Photomic

Case #547

47 year female

intracortical OGS

humerus

Lateral view

CT scan

Sagittal T-1 MRI

tumor

Post op x-ray after

wide resection and

allograft recon