Classification based on: Histological grade (G) Site (T) Metastases (M)

ENNEKING'S  SURGICAL STAGES   

STAGE GRADE SITE    METASTASES

1A  1B   

Low(G1) 

Low(G1)   

Intracompartmental(T1) 

Extracompartmental(T2)   

None(M0) 

None(M0)

2A 2B

High(G2) High(G2)

Intracompartmental(T1) 

Extracompartmental(T2)  

None(M0) 

None(M0)

3Low(G1) or

High(G2)

Intracompartmental(T1)  Or

Extracompartmental(T2)  Yes(M1)

Clinical examination (age, sex, site and past history) ◦ Thyroid ◦ Breasts ◦ Chest ◦ Liver ◦ Kidney ◦ Rectal (prostate & rectal tumours)

Bloods ◦ FBC (leukaemic cells etc) ◦ ESR (often elevated) ◦ Biochemistry (Ca++, PO4, liver enzymes and Alkaline Phosphatase) -> mets ◦ Acid Phosphatase (prostate and increased with metastatic deposits) ◦ Thyroid function tests ◦ PSA ◦ Serum Protein Electrophoresis (Myeloma)

Urinalysis Urine Bence-Jones (myeloma) CXR Abdominal ultrasound Bone scan -> other sites MRI -> soft tissue extent and association with nerves and vessels CT of lesion and chest (-> staging) Angiography -> tumour blood supply and relationship to major vessels Biopsy

Should know probable diagnosis and stage of tumour before biopsy

Performed by the surgeon who will perform the definitive surgery

Biopsy tract orientation & location is critical - will need to be included in the definitive surgery if lesion is malignant.

Meticulous haemostasis to avoid tracking haematomas

Send samples for microbiological analysis

Intra-lesional  ◦ through the tumour ◦ leaves macroscopic tumour ◦ not therapeutic

Marginal  ◦ through pseudo-capsule of tumour / reactive zone ◦ controls non-invasive benign tumours ◦ recurrence of malignant tumours = 25-50%

Wide ◦ around reactive zone, leaving a cuff of normal tissue ◦ skip lesions left ◦ recurrence of malignant tumours = < 10%

Radical  ◦ removal of entire compartment or compartments ◦ distant metastases left

Amputation  ◦ should be thought of as a form of reconstruction where

surgical control of the tumour precludes useful function.

Benign Malignant Other

Birth - 5yr

1. Eosinophilic Granuloma [onion skin periosteal Rxn]

2. (Unicameral bone cyst- rare)

1. laeukaemia 2. Metastatic

Neuroblastoma

1. Osteomyelitis 2. healing/ stress

fracture

6-18yr

1. Unicameral Bone Cyst 2. Aneurysmal Bone Cyst 3. Nonossifying Fibroma 4. Eosinophilic

Granuloma 5. Enchondroma 6. Chondroblastoma 7. Chondromyxoidfibroma 8. Osteoblastoma

1. Ewings Sarcoma 2. Osteosarcoma

1. Osteomyelitis 2. Fibrous Dysplasia 3. Osteofibrous

Dysplasia

19-40yr

1. Giant Cell Tumour 2. Eosinophilic granuloma

1. Ewings Sarcoma

40+yrs

1. Metastases (lung, breast, prostate, renal, thyroid, colon)

2. Multiple Myeloma 3. Lymphoma 4. Osteosarcoma

(Pagets) 5. Chondrosarcoma 6. Fibrosarcoma/

Malignant Fibrous 7. Histiocytoma

1. Hyperparathyroidism 2. Osteomyelitis 3. Paget's

FibroxanthomaFibrous cortical defectNon ossifying fibroma

Fibrosarcoma

Fibrous dysplasia

Round cell lesionsEwingsReticulum cell sarcomaMyeloma

Chondromyxoid fibromaChondrosarcoma

Osteoid osteoma

Cortical fibrous dysplasia Adamantinoma

DIAPHYSISDIAPHYSIS

osteosarcoma Enchondroma

Giant cell tumour

osteochondroma

Bone cyst Osteoblastoma

Chondromyxoid fibromaChondrosarcoma

FibroxanthomaFibrous cortical defectNon ossifying fibroma

METAPHYSISMETAPHYSIS

chondroblastoma

Articular osteochondromaDysplasia epiphysealis

hemimelica

Giant cell tumour

EPIPHYSISEPIPHYSIS

Fibrous DysplasiaOsteoblastomaGiant Cell Tumour Metastasis/ Myeloma Aneurysmal Bone Cyst Chondroblastoma/ Chondromyxoid Fibroma Hyperparathyroidism (brown tumour)/ Haemangioma Infection Non-ossifying Fibroma Eosinophilic Granuloma/ Enchondroma Simple Bone Cyst

Vascular ◦ hemangiomas ◦ infarct

Infection ◦ chronic osteomyelitis

Neoplasm ◦ primary

osteoma osteosarcoma

◦ metastatic prostate breast other

Drugs ◦ Vitamin D ◦ fluoride

Inflammatory/Idiopathic Congenital

◦ bone islands ◦ osteopoikilosis ◦ osteopetrosis ◦ pyknodysostosis

Autoimmune Trauma

◦ fracture (stress) Endocrine/Metabolic

◦ hyperparathyroidism Paget's disease

Pattern of bone destruction Tumour matrix Cortical expansion/penetration Periosteal reaction Adjacent soft tissues Size & shape of lesion Trabeculation Growth Plate

Benign lesion - during growth 20% of benign bone lesions Age 5-15 years Not found in adults Sex m:f 3:1 The most common location is the proximal humerus

(67%) followed by the proximal femur (15%) unusual sites (calcaneum, pelvis) in patients >17

yrs

Cysts may be Active or Latent: Active cysts are located near the growth plate, but they move further away as the child grows and become inactive (latent)

Well defined, central osteolytic area with a thin sclerotic margin

Metaphyseal in young - moves towards diaphysis with growth

It fills and slightly expands metaphysis

Pathology Thin walled cavities - blood tinged fluid. The lining cells are cuboidal,

Treatment goal is to minimise fracture risk until the cyst heals (but this can take years)

Steroid injection ◦1-3 percutaneous injections repeated at 2

monthly intervals ◦60-80% success rate

Curettage and bone graft -  50% recurrence rate and possibility of damage to the growth plate  

Bone marrow aspirate has recently been used

Benign solitary, expansile and erosive lesion of bone 1% of benign bone lesions Age (85% cases <20 years old) Sex f:m is 2:1 ABC's can be found in any bone in the body The most common location is the metaphysis of the lower extremity long bones, more so than the upper extremity The vertebral bodies or arches of the spine may be involved Approximately one-half of lesions in flat bones occur in the pelvis

Presentation Swelling, tenderness and pain Limited range of motion due to joint obstruction Spinal lesions - neurological symptoms Pathological fractures are rare - eccentric location of the lesion

Placed eccentrically in the metaphysis and appears osteolytic

The periosteum is elevated; cortex is eroded to a thin margin

The expansile lesion - "blow-out” CT scan -for pelvis or spine lesions CT scan can demonstrating multiple fluid-fluid levels MRI can also confirm the multiple fluid-fluid levels

A slow growing, indolent ABC has been observed to regress spontaneously

Most lesions can be treated with curettage and application of a high-speed burr

Recurrence was statistically related to young age and open growth plates, and may be less likely following wide excision than following curettage

Benign, usually solitary and locally aggressive

10% of benign bone lesions malignant transformation (5-10%) Not seen until after the growth plate

closes Rarely metastasises (<1% to lungs) Age 20 - 40 years More common females Most commonly seen in the distal

femur, proximal tibia and the distal radius

Nearly always located at the very end of a long bone (metaphyseal / epiphyseal)

Pathological fracture occurs in 10 - 15% Neighbouring joint often irritated

(effusion)

stagestage clinicalclinical radiologyradiology histologyhistology

II asymptomaticasymptomatic benignbenign benignbenign

IIII symptomaticsymptomatic activeactive benignbenign

IIIIII symptomaticsymptomatic AggressiveAggressive

Mets +Mets +

benignbenign

Usually well defined lesion in the epiphysis extending up to the joint surface without marginal sclerosis, cortex thinned and sometimes ballooned  

soap bubble appearance Junction with normal bone

poorly defined

Soft, friable tumour Cut surface tan in colour,

with areas of necrosis and haemorrhage

Numerous multinucleated giant cells. The stromal cells are homogenous mononuclear round/ovoid with large nuclei

Up to 50% have soft tissue extension

Intralesional excision by "extended" curettage Curettage alone has a high local recurrence rate (50%) and

the curettage is "extended" into the bone by a few millimetres by either using a burr, liquid nitrogen or phenol

The resulting cavity can be filled with bone graft or cement

En-bloc resection is possible if the bone is expendable e.g. proximal fibula, proximal radius

Amputation reserved for massive local recurrence, malignant change or infection

Radiotherapy reserved rare cases of unresectable tumours because of increased risk of secondary malignancy

10% of benign bone tumoursMale : Female 2:1Peak age 5 - 25 years (85% in this range)Rare over 40 years

Location:    Any bone, rarely multifocal    tibia & femur in 50%     spine - posterior elements     Only occurs in bones formed by endochondral ossification

Clinically Pain - commonest presentation

Pain - worse at night and relieved by aspirin10% occur in the spine Runs a self limiting course > surgery for pain reliefPain usually decreases as the lesion maturesLesion healed by 3 - 7 years

Lytic nidus surrounded by sclerotic bone (which may mask the nidus)Centre of nidus may be calcifiedCT or tomograms -> diagnosis Hot spot on bone scan

Differential Diagnosis Bone island (enostosis) Brodie's abscess Osteoblastoma fatigue fracture

NSAIDs ◦ relieves symptoms

Surgical: ◦Nidus excision -> no recurrence◦ Intraoperative localisation with:

Bone scan Tetracycline under UV light) CT X-Ray excised tissue -> contains nidus

Percutaneous radiofrequency coagulation

Cartilage capped bony projection / exostosisCommonest benign tumourDevelopmental abnormality of the metaphysis

Accounts for 45% of benign bone tumours

12% of all bone tumours most become evident under 20 years May be solitary or multiple (diaphyseal

aclasis) Any bone developing by endochondral

ossification may be involved

Autosomal dominant Disordered endochondral growth Multiple osteochondromas Short stature and bowing of limbs Treat individual lesions as

necessary and observe for malignant change

Malignancy Risk = ~ 20% overall or 0.2% per lesion

Trevor's Disease: Osteochondroma on epiphyseal side of the growth plate

x-ray hallmark is blending of tumour into underlying metaphysis

flat, sessile lesion or a peduculated (stalk like) process

pedunculated osteochondromas are oriented in proximal direction

Cartilaginous cap displays irregular areas of calcification

Nil required unless symptomatic (persistent irritation (from bursitis or tendon) or neurovascular compromise)

Extra capsular marginal excision ◦ Including the cartilaginous cap & overlying

perichondrium ◦ Deep bony base has minimal activity & may be

removed piecemeal ◦ The cartilaginous cap should not be traumatised

during removal ◦ Recurrence = < 5% 

Decreased risk of recurrence if excised after maturity

Risk of malignant change ~ 0.2% in a solitary lesion

Risk of malignant change in diaphyseal aclasis 20%

Sarcomatous change usually ->low grade Evidence of transformation to

Chondrosarcoma:  ◦ Cartilaginous cap thicker than 1 cm in an adult

(in child may be 2-3 cm thick)  ◦ Cartilage cap > 8cm diameter ◦ Fluffy outline ◦ Bone scan - Marked increase in uptake in an

adult  ◦ CT/MRI - soft tissue mass or displacement of a

major neurovascular bundle

10% of benign bone tumours 50% occur in small bones of the hands and

feet 15% femur and 12% humerus Peak incidence 10 - 50 years May be solitary or multiple (Olliers, Mafuccis)

Clinically Usually metaphyseal 75% Solitary 60% present as fractures pathological fracture, lump incidental finding

X-Rays Scalloped erosions on endosteal surface

flecks of calcification - sometimes called 'ground glass'

enchondroma (typical appearance & site)

Macroscopically - bluish white well demarcated

hypocellular; nests of mature cartilage cells,

Ollier's disease - more cellular; 50% ->malignant transformation

Mafucci's disease - associated with multiple haemangiomata and associated with nearly 100% malignant change somewhere

Observe - x-ray 6 months & 1 year after presentation

Curettage and grafting if latent Recurrence - en block excision Prognosis Risk of malignant change in Olliers is 50% malignant change in Mafuccis is nearly

100%

5 - 20% benign bone lesions usually monostotic Affects children and adolescents Median age at onset 8 years Male > Female (Albrights - Female > Male)

McCune - Albrights Syndrome Polyostotic disease (unilateral usually) Skin pigmentation 

◦ cafe au lait spots with serrated borders (called "coast of Maine") that tend to stop abruptly at the midline of the body

Precocious puberty (endocrinopathy) usually presents earlier, may be unilateral or widespread,

affecting long bones, hands, feet & pelvis  Malignant transformation (chondrosarcoma or osteosarcoma) is

about 4 %;

Lucent lesion in medullary space Sclerotic margin. Ground glass appearance No periosteal reaction Shepherds crook - proximal femur expansion of cortex

Pathology Bone replaced by firm, whitish

tissue of gritty consistency bone trabeculae separated by

fibrous tissue.  Bone is woven rather than lamellar 

Pagets disease FCD Hyperparathyroidism osteoblastoma osteosarcoma

Treatment Monostotic -> curettage and grafting if symptomatic Polyostotic -> symptomatic treatment May require osteotomy for deformity or lengthening / shortening

procedures

Prognosis Monostotic lesions cease activity at puberty but may be reactivated

by pregnancy Polyostotic - 85% -> pathological fracture malignant change occurs after radiotherapy