PRIMARY BONE TUMORS

PRESENTER: ONDARI N.J

FACILITATOR: PROF. GAKUU

28-10-2013

Outline

Introduction Classification Epidemiology Evaluation Staging Principles of management Selected tumors Therapeautic advances

Introduction

Forms 0.2% of human tumor burden

Primary malig bone tumors make 1% of all malignant tumors

Carcinoma commonly metastasize to LN except BCC

Sarcomas commonly metastasize hematogenously

Most have male predominance excep GCT, ABC

Classification

Based on tissue of origin Bone Cartilage Fibrous tissue Bone marrow Blood vessels Mixed Uncertain origin

Evaluation

History

Physical examination

Investigations; labs, imaging

Biopsy

Analytic approach to evaluation of the bone neoplasm

Evaluation; history

Age

Symptomatology Pain Swelling History of trauma Neurological sympts

Pathological fracture

Evaluation; physical examination Lump/swelling

5S MTC

Effusion

Deformities

Regional nodes

Evaluation; imaging

Plain radiograph

CT scan

MRI

Radionuclide scanning

PET

Radiography

Information yielded by radiography includes : Site of the Lesion

Borders of the lesion/zone of transition

Type of bone destruction

Periosteal reaction

Matrix of the lesion

Nature and extent of soft tissue involvement

Radiographic features of bone tumors

Site of the Lesion

Determined by the laws of field behavior and developmental anatomy of the affected bone, a concept first popularized by Johnson. Parosteal osteosarcoma -posterior aspect of the distal

femur Chondroblastoma -epiphysis of long bones before skeletal

maturity Adamantinoma and osteofibrous dysplasia have a specific

predilection for the tibia A lesion's location can also exclude certain entities from the

differential diagnosis. E.g Giant cell tumor -articular end of bone.

Location in relation to the central axis of the bone esp in long tubular bone, such as humerus, radius, femur, or tibia. For example, simple bone cyst, enchondroma, or a focus of

fibrous dysplasia -always centrally located Eccentric location is Xteristically observed in aneurysmal

bone cyst, chondromyxoid fibroma, and nonossifying fibroma

Predilection of Tumors for Specific Sites in the Skeleton

Parosteal osteosarcoma Chondroblas

toma

Adamantinoma

Site of the lesion.

Distribution of various lesions in a long tubular bone in a growing skeleton

Site of the lesion. Distribution of various lesions in a long tubular bone after skeletal maturity

Location of epicenter of lesion usually determines site of its origin (medullary, cortical, periosteal, soft tissue, or in the joint)

Site of the lesion.

Malignant lesions are seen predominantly in its anterior part (body)

Distribution of various lesions in a vertebra.

Benign lesions predominate in its posterior elements.

Borders/margins of the Lesion

Margins determined by GRate hence benign or malignant

Three types of lesion margins are encountered: Sharp demarcation by sclerosis (IA margin), sharp demarcation without sclerosis (IB margin) Ill-defined margin (IC margin)

Slow-growing lesions -sharp sclerotic borders; usually indicates that a tumor is benign E.g nonossifying fibroma, simple bone cyst

Indistinct borders- typical of malignant or aggressive lesions

Post- Radio- or chemo of malignant bone tumors Can exhibit sclerosis and a narrow zone of transition

Borders of the lesiondetermine its growth rate.

sharp sclerotic sharp lytic ill-defined.

A: Sclerotic border typifies a benign lesion e.g nonossifying fibroma in the distal femur.

B: A wide zone of transition typifies an aggressive or malignant lesion e.g plasmacytoma involving the pubic bone and supraacetabular portion of the right ilium

Borders of the lesion.

Type of Bone Destruction

Mechanisms of bone destruction Direct effect of tumor cells Incr osteoclastic activity

Cortical bone is destroyed less rapidly than trabecular bone. Loss of cortical bone appears earlier on radiography trabecular bone must be destroyed (about 70% loss of

mineral content) before the loss becomes radiographically evident

Bone destruction can be described as geographic (type I) - benign lesions moth-eaten (type II) and permeative (type III) - rapidly growing infiltrating

tumors

Patterns of bone destruction. geographic

a uniformly affected area within sharply

defined borders

moth-eaten

rapidly growing infiltrating lesions

permeative type

characteristic of round cell tumors

myeloma Ewing sarcomagiant cell tumor.

Periosteal Response the pattern of periosteal reaction is an indicator of the

biologic activity of a lesion . periosteal reactionsthat can be categorized as;

uninterrupted (continuous) or I nterrupted (discontinuous).

Any widening and irregularity of bone contour may represent periosteal activity.

An uninterrupted periosteal reaction indicates a long-standing (slow-growing), usually indolent, benign process.

There are several types of solid periosteal reaction: a solid buttress e.g aneurysmal bone cyst and chondromyxoid

fibroma; a solid smooth or elliptical layer e.gosteoid osteoma and

osteoblastoma; a single lamellar reaction, such as accompanies Langerhans cell

histiocytosis Sunburst (“hair-on-end”) or onion-skin (lamellated) pattern

. Codman triangle

An uninterrupted periosteal reaction usually indicates a benign process, whereas an interrupted reaction indicates a malignant or aggressive nonmalignant process

Types of periosteal reaction.

Examples of Nonneoplastic and Neoplastic Processes Categorized by Type of Periosteal Reaction

Interrupted type of periosteal reaction

sunburst pattern -osteosarcoma

lamellated or onion-skin type in ewing sarcoma

Ewing sarcoma -lamellated type

Codman triangle (arrow)

Type of Matrix The matrix represents the intercellular material produced

by mesenchymal cells E.g osteoid, bone, chondroid, myxoid, and collagen material .

Type of matrix allows differentiation of some similar-appearing E.g differentiating osteoblastic from chondroblastic processes.

Calcifications in the tumor matrix, point to a chondroblastic process. Calcifications typically appear as punctate (stippled),

irregularly shaped (flocculent), or curvilinear (annular or comma-shaped, rings and arcs).

Differential diagnosis of stippled, flocculent, or ring-and-arc calcifications includes enchondroma, chondroblastoma, and chondrosarcoma.

A completely radiolucent lesion may be either fibrous or cartilaginous in origin tumor-like lesions, such as simple bone cysts or intraosseous

ganglion

C. by the presence of a solid sclerotic mass, such as in parosteal osteosarcoma

Types of matrix: osteoblastic

A. fluffy, cotton-like densities within the medullary cavity, e.g in this case of osteosarcoma of the distal femur

B. presence of the wisps of tumor-bone formation, like in this case of osteosarcoma of the sacrum

The matrix of a typical osteoblastic lesion is characterized by the presence of the following features

Types of matrix: chondroid matrix A: Schematic representation of various appearances of chondroid matrix calcifications.

B: Enchondroma displays a typical chondroid matrix

C: Chondrosarcoma with characteristic chondroid matrix

Soft Tissue Mass

A bone lesion associated with a soft tissue mass should prompt the question of which came first.

Is the soft tissue lesion an extension of a primary bone tumor, or is it a primary soft tissue tumor invading bone?

Radiographic features differentiating primary soft tissue tumor invading bone from primary bone tumor invading soft tissues.

Benign Versus Malignant Nature clusters of features that can be gathered from

radiographs can help in favoring one designation over the other .

Benign lesions usually have well-defined sclerotic borders exhibit a geographic type of bone destruction the periosteal reaction is solid and uninterrupted, and there is no soft tissue mass.

Malignant tumors often exhibit poorly defined borders with a wide zone of

transition; bone destruction appears in a moth-eaten or

permeative pattern, and the periosteum shows an interrupted, sunburst, or

onion-skin reaction with an adjacent soft tissue mass.

NB-benign lesions may also exhibit aggressive features

Radiographic features that may help differentiate benign from malignant lesions

Grading of bone sarcomas

Criteria for grading Cellularity Nuclear features Mitotic figures necrosis

Correlates with prognosis in some tumors E.g chondrosarcoma, malig vascular tumors

Some not amenable to histological grading e.g monomorphic tumors Ewing, MM, lymphoma

Some always high grade Sometimes not useful in predicting prognosis

Adamantinoma, chordoma

Staging of bone tumors

Benign tumors (Enneking staging of benign tumors) Stage 1 - latent Stage 2 - active Stage 3 - aggressive

Malignant tumors TNM staging AJCC staging system Musculoskeletal tumor society staging

system(enneking) Surgical staging

Note Benign tumors - classified using Arabic

numerals(1,2,3) Malignant tumors - classified using roman

numerals(I,II,III)

William F. Enneking M.D

Enneking classification systems

Enneking classification of benign tumors Latent, active, aggressive

Enneking surgical staging of malignant tumors

Enneking classification of local procedures Intracapsular, marginal, extended, radical

Enneking classification of amputations Intracapsular, marginal, extended, radical

Enneking classification of local procedures

Enneking classification of amputations

Enneking staging of benign tumors

Stage 1; Latent Well defined margin Grows slowly and then stops Heals spontaneously eg osteoid osteoma Neglible recurrence after intracapsular resection

Stage 2; Active Progressive growth limited by natural barriers Well defined margin but may expand thinning cortex e.g ABC Negligible recurrence after marginal excision Rx marginal resection

Stage 3; aggressive Growth not limited by natural barriers e.g GCT Mets present in 5% of these pts Have high recurrence after intracapsular or marginal

resection Extended resection preferred

Enneking surgical Staging of malignant tumors

Incorporates

degree of differentiation Low grade(stage I) or High grade(stage II)

Local extent of tumor Intracompartmental - A Extracompartmental - B

distant spread metastasis

Enneking surgical Staging of malignant tumors

AJCC staging for bone sarcomas Based on

Tumor grade Low grade(I) High grade(II)

Tumor size <8cm -A >8cm -B

Presence and location of mets Skip mets -III Pulm mets -IVA Non-pulm mets -IVB

Bone biopsy

Options Needle biopsy

90% accuracy at determining malignancy Accuracy at determining specific tumor much lower Absence of malignant cells less re-assuring than

incisional biopsy Core biopsy

Provides accurate diagnosis in 90% of cases incisional biopsy

Primary resection instead of biopsy can be done in; Small(<3cm) subc mass- marginally resected if

likely malignant Characteristic radiographic appearance of benign

lesion Painful lesion in an expendable bone e.g prox

fibula, distal ulna

Tumour Biopsy Principles 1

1.Biopsy done only after evaluation & imaging is complete. determine xteristics and local extent of the tumor and mets Staging helps determine the exact anatomic approach to tumor Biopsy superimposes radiologic changes at the biopsy site, and

there4 can alter the interpretation of the imaging studies.

2. Place small incisions whenever possible- skin & capsule

3. The biopsy track be considered contaminated with tumor cells. Track excised en bloc with the tumor subsequently.

4. The surgeon should be familiar with incisions for limb salvage surgery, and also with standard and nonstandard amputation flaps. 

Needle biopsy track contaminated patellar tendon

Multiple needle tracks contaminate quadriceps tendon

Needle track placed posteriorly, location that would be extremely difficult to resect en bloc with tumor if it had proved to be sarcoma.

Examples of poorly performed biopsies

Tumour Biopsy Principles 2

5. If a tourniquet is used; The limb is elevated before inflation Avoid exsanguination by compression.

6. contaminate as little tissue as possible. Avoid transverse incisions The deep incision should go thru single

muscle compartment (muscle belly) rather than through an intermuscular plane.

Major neurovascular structures should be avoided.

Care should be taken not to contaminate flaps.

Minimal retraction should be utilized to limit soft tissue contamination.

Example of poorly performed biopsy

Transverse incisions should not be used

Tumour Biopsy Principles 3

7. If possible soft tissue extension of a bone lesion should be sampled 

8. If a hole must be made in the bone, it should be round or longitudinally oval to minimize stress concentration and prevent a subsequent fracture. A fracture may preclude a subsequent limb

salvage surgery. PMMA is plugged into the hole to contain a

hematoma - minimal.  

9. Biopsy should be taken from the periphery of the lesion, which contains the most viable tissue. Biopsy material may be sent for M/C/S if in doubt

regarding infection

If hole must be made in bone during biopsy, defect should be round to minimize stress concentration, which could lead to pathological fracture

Biopsy resulted in irregular defect in bone, which led to pathological fracture

Examples of poorly performed biopsies

Tumour Biopsy Principles 4

10. A frozen section should be sent intraop to ensure that diagnostic tissue has been obtained. If a tourniquet has been used it should be deflated

and meticulous haemostasis ensured before closure.

11. Drains should not be used routinely. If a drain is used, it should exit in line with the

incision. The wound should be closed tightly in layers.

12. operating surgeon should accompany specimen to pathologist if feasible Discuss with the pathologist about clinical findings,

imaging, intraop findings and the specimen

Drain site was not placed in line with incision

Example of poorly performed biopsy

Principles of management

Multidisciplinary team approach Benign asymptomatic tumors

If certain observe If in doubt biopsy

Benign symptomatic or enlarging tumors Biopsy Excision/ curretage

Suspected malignant tumors If primary admit for work-up Staging Choices; amputation, limb sparing surgery,

adjuvant therapy

Benign tumors - not aggressive

Bone-forming tumors   Osteoid osteoma Bone island

Cartilage lesions    Chondroma Osteochondroma

Fibrous lesions Nonossifying fibroma Cortical desmoid Benign fibrous

histiocytoma Fibrous dysplasia Osteofibrous dysplasia Desmoplastic fibroma

  

Cystic lesions Unicameral bone cyst Aneurysmal bone cyst Intraosseous ganglion cyst Epidermoid cyst

Fatty tumors Lipoma

Vascular tumors Hemangioma

Other nonneoplastic lesions Paget disease Brown tumor-

hyperparathyroidism Bone infarct Osteomyelitis

Aggressive benign tumors Giant cell tumor

Chondroblastoma

Chondromyxoid fibroma

Osteoblastoma

 Langerhans cell histiocytosis

Osteoid Osteoma

Bone Island

CARTILAGE LESIONS

Enchondroma

Olliers disease

Maffuci synrome

Chondroma

CARTILAGE LESIONSOsteochondroma

Fibrous lesionsNonossifying fibroma

Shepherd’s crook appearance

Polyostotic Fibrous dyspalsiaFibrous dysplasia

Cystic lesions

Unicameral bone cystAneurysmal bone cyst

Aggressive benign tumors

Giant cell tumor Chondroblastoma

Chondromyxoid fibroma

Aggressive benign tumors

Malignant Tumors of Bone Osteosarcoma Chondrosarcoma Ewing sarcoma Chordoma Adamantinoma Malignant vascular tumors Malignant fibrous histiocytoma and

fibrosarcoma Multiple myeloma and plasmacytoma Lymphoma Metastatic carcinoma

Osteosarcoma

Chondrosarcoma

Ewing Sarcoma

may be confused with osteomyelitis

Commonly affects diaphysis with onion skin appearance

Adamantinoma

Bubble-like appearance

85% occur in tibia

The end

Thank you