Transcript Primary bone tumors
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
Site of the lesion.
osteosarcoma Adamantinoma Chondroblastoma
Site of the lesion.
Distribution of various lesions in a long tubular bone in a growing skeleton Distribution of various lesions in a long tubular bone after skeletal maturity
Site of the lesion.
Location of epicenter of lesion usually determines site of its origin (medullary, cortical, periosteal, soft tissue, or in the joint)
Distribution of various lesions in a vertebra. Malignant lesions are seen predominantly in its anterior part (body) 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 lesion determine its growth rate. sharp sclerotic sharp lytic ill-defined.
Borders of the lesion.
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
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
geographic Patterns of bone destruction. moth-eaten a uniformly affected area within sharply defined borders rapidly growing infiltrating lesions permeative type characteristic of round cell tumors
giant cell tumor. myeloma Ewing sarcoma
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
Types of periosteal reaction.
An uninterrupted periosteal reaction usually indicates a benign process, whereas an interrupted reaction indicates a malignant or aggressive nonmalignant process
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
Types of matrix: osteoblastic The matrix of a typical osteoblastic lesion is characterized by the presence of the following features 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 C. by the presence of a solid sclerotic mass, such as in parosteal osteosarcoma
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.
Examples of poorly performed biopsies 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.
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
Examples of poorly performed biopsies Biopsy resulted in irregular defect in bone, which led to pathological fracture
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
Example of poorly performed biopsy Drain site was not placed in line with incision
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
Chondroma CARTILAGE LESIONS Enchondroma Olliers disease Maffuci synrome
CARTILAGE LESIONS Osteochondroma
Nonossifying fibroma Fibrous lesions Fibrous dysplasia Polyostotic Fibrous dyspalsia Shepherd’s crook appearance
Unicameral bone cyst Cystic lesions Aneurysmal bone cyst
Giant cell tumor Aggressive benign tumors Chondroblastoma
Aggressive benign tumors Chondromyxoid fibroma
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