Volume 3

Osteosarcoma Variants

Hemorrhagic osteosarcoma------------Case 110 & 499-503Parosteal osteosarcoma-----------------Case111 & 504-510Periosteal osteosarcoma----------------Case 112 & 511-517Pagetic sarcoma-------------------------Case 113 & 518-528Low grade intramedullary OGS------Case 114 & 528.1-530Radiation induced OGS---------------Case 115 & 531-537Multicentric osteosarcoma------------Case 116 & 538-542Soft tissue osteosarcoma--------------Case 118 & 543-545Intracortical osteosarcoma------------Case 119 & 546-547

Osteogenic Osteogenic SarcomaSarcomaVariantsVariants

HemorrhagicHemorrhagicOsteogenic Osteogenic SarcomaSarcoma

Hemorrhagic (Telangiectatic) Osteosarcoma The hemorrhagic (OGS), an extremely lytic and hemorrhagicvariant of the osteosarcoma, presents in the same age group andlocation as a classic osteosarcoma but has a radiographic appearance almost identical to that of an aggressive aneurysmalbone 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 aneurysmalbone cyst. Even microscopically, many areas of the hemorrhagicOGS will have the appearance of an aneurysmal bone cyst withonly an occasional mitotic figure. For this reason, it is very important for the surgeon who performs the biopsy to obtainan adequate specimen with good sampling by means of an open biopsy as apposed to a simple needle biopsy. The microscopicfeatures 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 verylittle 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 thatcome potential problems for the treating orthopedic surgeon whomust 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 OGSwas 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.

CLASSICCase #110

23 year malehemorrhagic OGSproximal humerus

Aneurysmal lesion

Coronal T-1 MRI

hemorrhagictumor

Coronal T-1 MRIthru 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 withalloprostheticreconstruction

Neer

allograft

18 year followup x-rays

Case #499

15 year male hemorrhagic OGSdistal femur

Lateral view

Bone scan

Sagittal T-2 MRI

tumor

hemorrhagictumor

Coronal T-2 MRI

Axial T- 2 MRI

tumor

Photomic

blood

3 yrs post op Compresstotal knee reconstruction

CPS

osseo-integration

Case #500

19 year malehemorrhage OGSproximal femur

Looks like ABC

Lateral view

Initial biopsy reveals aneurysmal bone cyst

6 weeks latershows lysis ofouter shell

Repeat biopsyreveals hemorrhagic OGS

Hip disarticulation specimen

tumor

femoral head

2nd biopsy Photomic

Case #501

6 year femalepath fracture thruunicameral bone cyst

Lateral view

cysticlesion

7 weeks aftersteroid injection

cyst

1 month later andprogressive lyticdestruction

Biopsy here shows hemorrhagic OGS

Case #501.1

19 year old male with acute onset of pain 2 wksago 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 malelooks likeunicameral bone cyst

cysticlesion

Progressive lysisafter steroid injection

2 months laterwith progressivelysis and lookingmalignant

Biopsy reveals hemorrhagic OGS

Clinical appearance before shoulder disarticulation

Case #503

17 year femalehemorrhagic OGSC-3

AP view

CT scan

Photomic

6 years later withspontaneous fusionand no tumor

ParostealParostealOstogenic Ostogenic SarcomaSarcoma

Parosteal Osteosarcoma The parosteal (OGS) is a low grade variant arising from the surfaceof 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 clearlyseparates it from the classic OGS. It is seen more commonly in females than males and is found in a slightly older age groupthan 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 apalpable tumor mass that might have been present many years before medical advise was sought. Histologically, this tumor has avery low mitotic index and in many cases can be confused witha normal healing fracture callous with occasional areas of cartilagebeing seen. Because this tumor is extremely low grade, it is not

responsive to adjuvant therapy such as chemotherapy orradiation 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 afterthe 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.

CLASSICCase #111

32 year maleparosteal OGSdistal 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 maleparosteal OGSdistal 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 withrecurrence as a highgrade dedifferentiatedparosteal OGS

tumor

Another view

tumor

Photomic of recurrence

Close up of osseointegration ofCompress implant

Case #505

32 year maleparosteal OGSproximal humerus

tumor

Axillary view

tumor

CT scan

tumor

Amputation specimen cut in path lab

Photomic

Case #506

25 year male parosteal OGSdistal femur

Distal femoralresection specimen

tumor

Cut specimen in path lab

tumor

fattymarrow

Case #507

13 year maleparosteal OGSmid femur

AP view

Lateral view

CT scan

Segmental resection specimen

Autoclaved bone replaced with IM nail fixation

Post op x-ray2 years later

autoclavedbone

Case #508

17 year male with parosteal OGS mid tibia

Lateral x-ray

CT scan

tumor

Bone scan

Segmental resectionmid tibial lesion

biopsysite

Surgical specimen cut in path lab

tumor

Allograft reconstruction over IM nail

X-ray 1 year later

Case #509

41 year femaleparosteal OGShumerus

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

PeriostealPeriostealOsteogenic Osteogenic SarcomaSarcoma

Periosteal Osteosarcoma

The periosteal osteosarcoma is another surface type OGS thattends to be low grade to intermediate with potential for pulmonarymetastasis in about 25% of cases. It accounts for 2% of all OGS’sand, compared to the parosteal OGS, has a much higher percentage of cartilagenous tissue in the tumor to the point where it can looklike 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 lifeand 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 utilizedunless 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 followingwide 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 resectionproximal tibia tumor

bulge

Cut specimenin path lab

tumor

Photomic

Proximal tibia resected ready for reconstruction

Post op x-ray withalloprostheticreconstruction

TKA

allograft

Case # 512

9 year femaleperiosteal OGStibia

AP x-ray

Lateral view

Cut specimen in path lab followingAK amputation

Photomic

Higher power

Case #513

14 year maleperiosteal OGS

Sagittal T-2 MRI

Axial T-1 MRI

Axial T-2 MRI

Case #514

26 year femaleperiosteal OGSdistal femur

Lateral view

X-ray 10 yearsfollowing wideresection and cementedprosthetic reconstruction

stressshielding

Case #515

12 year femaleperiosteal OGStibia

Bone scan

Axial T-1 MRI

Photomic

Case #516

15 year maleperiosteal OGSdistal tibia

CT scan

Bone scan

Photomic

Case #517

39 year femaleperiosteal OGSpseudotumor

In fact is a Nora’slesion orbizarre parostealosteochondromatousproliferation (BPOP)

Bone scan

CT scan

Axial Gad contrast MRI

edema

Sagittal PD

Sagittal T-2 MRI

edema

Axial gad contrast MRI

Pagetic Pagetic SarcomaSarcoma

Pagetic Sarcoma

There are multiple diseases of the skeletal system that can resultin a secondary form of OGS most likely brought about by a secondmutation 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’sdisease, 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 PageticOGS 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’sdisease but then suddenly develop an acute new pain in the area ofthe older pain with x-ray evidence of recent lysis and destruction

of old Pagetic reactive bone. The prognosis for survival in thissecondary form of OGS is extremely poor with only about 8%surviving, mainly because the older age group in which the diseaseoccurs 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 femalePagetic sarcomapelvis

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 withPagetic sarcomahumerus

tumor

old Paget’s

new

Macro sectionfrom amputationspecimen tumor

Photomic

Post op x-ray following forequarter amputation

Case # 520

73 year femalePagetic sarcoma skullready for resection

Lateral view of skull

Occipital view

Tangential view

tumor

Resected specimen cut in path lab

Photomic

Case #521

82 year male Pagetic sarcomadistal humerus

old Paget’swith priorfracture

Close up of new tumor

tumor

Photomic

Case #522

80 year femalePagetic sarcoma distal humerus

Case #523

84 male with multi focal Pagetic sarcoma

femur

humerus

Case #524

83 year malePagetic sarcomafemur

Case #525

60 year malePagetic sarcomafemur

Lateral view

Photomic

Photomic

Case #526

78 female Pagetic sarcomaproximal tibia

Lateral view

tumor

Case #527

92 year malePagetic sarcoma tibia

Case #528

78 year femalePagetic sarcomalumbar spine

Low Grade Low Grade IntramedullaryIntramedullary

Osteogenic Osteogenic SarcomaSarcoma

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 confinedwithin 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 corticalanatomy. The smoky appearance of metaphyseal bone suggests the diagnosis of chronic osteomyelitis or perhaps fibrous dysplasia.Microscopically, the tumor has a histological appearance similarto 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.

CLASSICCase #114

63 year femaleintramedullary OGSdistal femur

Lateral view

Bone scan

CT scan

tumor

Macro section fromresected specimen

tumor

Photomic

Photomic

Case #528.1

51 year femalelow grade intramedullary OGSdistal 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 femalelow grade intramedullary OGSdistal femur

tumor

Lateral view

CT scan

Photomic

Case #530

56 year malelow gradeintramedullary OGSdistal tibia

tumor

Lateral view tumor

Bone scan

Photomic

Radiation-Radiation-inducedinduced

Osteogenic Osteogenic SarcomaSarcoma

Radiation-induced Osteosarcoma

One of the most malignant forms of OGS is the secondary typeinduced 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. Theaverage delay for the occurrence of secondary OGS is 15 years,with a range from 3 to 55 years. The prognosis for this variant isextremely poor, similar to Pagetic OGS. It has a very high rate of metastasis to the lung for which chemotherapy is not very effective.

CLASSICCase #115

33 year femaleradiation-inducedsarcoma 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 withpathologic fracture

Biopsy photomic

tumor

Higher power

Case #532

72 year maleradiation sarcoma pelvis

Prior radiation therapyfor prostate cancer3 years before

Another view at adifferent date withhip 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 CTcut thru L hipshowing large tumor

Upper CT cut thruSI area showingtumor 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 scapulawith prior radiation treatment for breast CA 12 yrs ago

tumor

Case #535

44 year female withradiation sarcomaproximal humerus 2ndto prior radiation forbreast cancer

tumor

Photomic with radiation OGS

Case #536

76 year maleradiation sarcomafemur

Prior history ofradiation therapyfor soft tissue tumor10 years ago

Bone scan

Photomic radiation OGS

Case #537

Elderly M.D. with longhistory working underX-ray fluoroscope

Now skin cancer andradiation sarcomaindex finger

X-ray of index finger sarcoma

tumor

Photomic radiation sarcoma

MulticentricMulticentricOsteogenic Osteogenic SarcomaSarcoma

Multicentric Osteosarcoma The multicentric variant of OGS is an extremely rare variantoccurring in approximately 1% of all OGS. It has two distinctcategories: (1) Synchronous multicentric OGS occurring in child-hood and adolescence. This is the more severe variant, consideredto 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 associatedwith 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 synchronousform 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.

CLASSICCase #116

8 year femalemulticentric OGS

Close up distal femur

Lateral view

Bone scan

Close up bone scan

Upper bodybone scan

Coronal T-1 MRI

Another coronal cutT-1 MRI

Sagittal T-1 MRI

Photomic

Another photomic

Case #538

18 year femalemulticentric OGSpelvis and femur

Gad contrast coronal MRI

tumor

tumor

Another Gad contrast cut

Axial T-2 MRI

pelvictumor

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 musclesto custom proximal femoral replacement implant

totalhip

femoral implant

Outer face of resected specimen

acetabulum

iliumtumor bulge

Inner face

tumor bulge

ilium

Closure

Post op x-ray

recon plateand screws

Case #539

16 year femalemulticentric OGS tumor

Proximal tibial lesion

Lateral view withskip lesion indistal tibia

Bone scan showing two lesions in tibia

Bone scan showingiliac lesion

Bone scan showingsternal lesion

Photomic from tibial biopsy

Proximal tibialresection andtotal knee reconstruction

tumorbulge

Proximal tibialprosthesis in positionready for relocationand closure

Reconstructioncompleted and ready for closure

Case #540

Multicentric OGSfemur and sacrum20 year male

Lateral view

Coronal T-1 MRIshowing tumor atboth ends of femur

Sagittal T-1 MRIdistal 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 MRIdistal femur

tumor

Sagittal T-2 MRIdistal femur

tumor

tibiallesions

Coronal T-1 MRIknee 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 TissueSoft TissueOsteogenic Osteogenic SarcomaSarcoma

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 groupsaround 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 ofthe lesion and aggressive, poorly mineralized tissue at the periphery, must be differentiated from myositis ossificans, whichhas a typical zonal pattern with peripheral maturation of bone formation. As with any soft tissue sarcoma, the treatment consistsof 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.

CLASSICCase #118

67 year malesoft tissue OGScalf

tumor

AP view

Sagittal T-1 MRI

tumor

Axial T-1 MRI

Cut surgical specimen in path lab

Photomic

Case #543

76 year femalesoft tissue OGScalf

Lateral view

CT scan

Bone scan

Axial T-1 MRI

Sagittal T-1 MRItumor

Photomic

Case #544

60 year female withsoft tissue OGS leg

Oblique view

Bone scan

Case #545

63 year male soft tissue OGShand tumor

Lateral view

Axial T-1 MRI

tumor

Axial T-2 MRI

tumor

Coronal T-2 MRI

tumor

Multiple pulmonary mets

IntracorticalIntracorticalOsteogenic Osteogenic SarcomaSarcoma

Intracortical Osteosarcoma

The intracortical OGS is perhaps the rarest variant of OGS withonly 14 cases described in the world literature since 1960. It occurs between the ages of 10 and 47 years, equally betweenmales and females, and is seen most typically in the femur or tibia as a metadiaphyseal lesion with a radiographic appearancevery similar to that of osteoid oasteoma. The prognosis is usually quite good with a total of three deaths in the world literature. Itis usually treated by wide resection without chemotherapy. Afew cases are higher grade and carry a poor prognosis similarto 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 monthsafter curettementwith recurrence

Bone scan at time of recurrence

Axial Gad contrast MRI same time

Sagittal PD MRIsame time

tumor

Unicortical segmental wide resection

tumor

Photomic of resected specimen

Post op x-ray followingunicortical resectionand allograft recon

allograft

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

tumor

PD T-2

Case #546

43 year femaleintracortical OGSdistal femur

Lateral view

Sagittal T-1 MRI

Sagittal T-2 MRI

tumor

Biopsy photomic

Photomic

Case #547

47 year femaleintracortical OGShumerus

Lateral view

CT scan

Sagittal T-1 MRI

tumor

Post op x-ray afterwide resection andallograft recon