bone neoplasms radiographic and pathologic correlation

Radiographic and Radiographic and Pathologic Pathologic

Characteristics of Characteristics of Common Bone Common Bone

NeoplasmsNeoplasms

Nick LuemNick Luem

Diagnostic RadiologyDiagnostic Radiology

June 24, 2007June 24, 2007

Classification of the more Classification of the more common bone tumorscommon bone tumors

Benign NeoplasmsBenign Neoplasms– OsteochondromaOsteochondroma– ChondromaChondroma– Giant Cell TumorGiant Cell Tumor– Aneurysmal Bone Aneurysmal Bone

CystCyst

Malignant Malignant NeoplasmsNeoplasms– Osteogenic Osteogenic

sarcomasarcoma– ChondrosarcomaChondrosarcoma– Ewing’s sarcomaEwing’s sarcoma

OsteochondromaOsteochondroma

Also known as exostosisAlso known as exostosis Children and teenagers most affected, Men Children and teenagers most affected, Men

>> Women>> Women Clinically appear as slow growing masses, Clinically appear as slow growing masses,

painful if impinging on nerve tissuepainful if impinging on nerve tissue Solitary or multipleSolitary or multiple Multiple Hereditary ExostosisMultiple Hereditary Exostosis autosomal autosomal

dominant disease with inactivation of both dominant disease with inactivation of both copies of EXT gene in growth plate copies of EXT gene in growth plate chondrocyteschondrocytes

OsteochondromaOsteochondroma

Benign projection of bone with cartilaginous Benign projection of bone with cartilaginous cap cap

Occurs in epiphyseal plate and grows laterallyOccurs in epiphyseal plate and grows laterally Exhibits cortex and medullary portionExhibits cortex and medullary portion May convert to malignancy if cartilage cap May convert to malignancy if cartilage cap

becomes thicker and contains disorganized becomes thicker and contains disorganized calcificationscalcifications

Conversion to sarcoma rare (<1%) but higher Conversion to sarcoma rare (<1%) but higher in patients with hereditary syndromein patients with hereditary syndrome

OsteochondromaOsteochondroma Ultrasound safe and inexpensive way to evaluate Ultrasound safe and inexpensive way to evaluate

thickness of cartilaginous capsulethickness of cartilaginous capsule

Develops in bones of endochondral origin and arises from the metaphysis near the growth plate of long tubular bones.

Occasionally develops from bones of the pelvis, scapula and ribs

MRI method of choice to evaluate thicknesss of MRI method of choice to evaluate thicknesss of cartilaginous cap to rule out malignant conversioncartilaginous cap to rule out malignant conversion

- Radiograph can demonstrate that cortex - Radiograph can demonstrate that cortex of osteochondroma blends with cortex of of osteochondroma blends with cortex of normal bonenormal bone

- Long axis of tumor usually runs parallel - Long axis of tumor usually runs parallel to parent bone and points away from to parent bone and points away from parent jointparent joint

Osteochondroma:

Disorganized growth plate with endochondral ossification

Newly made bone formsinner portion of head andstalk

Medullary cavity ofosteochondroma and bone are continuous

ChondromaChondroma

Slow-growing tumor of hyaline cartilageSlow-growing tumor of hyaline cartilage EnchondromasEnchondromasarise within medullary cavityarise within medullary cavity Juxtacortical chondromaJuxtacortical chondromaarise on bone surfacearise on bone surface Destroys normal bone by erupting as mixture of Destroys normal bone by erupting as mixture of

calcified and uncalcified hyaline cartilagecalcified and uncalcified hyaline cartilage Occur in children and young adultsOccur in children and young adults Enchondromas usually solitaryEnchondromas usually solitary Favor the metaphyseal region of tubular bones Favor the metaphyseal region of tubular bones

such as the small bones of the hand and feetsuch as the small bones of the hand and feet

ChondromaChondroma

Most asymptomatic and found incidentallyMost asymptomatic and found incidentally Occasionally cause pathologic fracturesOccasionally cause pathologic fractures Ollier diseaseOllier disease syndrome of multiple syndrome of multiple

enchondromasenchondromas Maffuci syndromeMaffuci syndromeenchondromatosis enchondromatosis

associated with soft tissue hemagiomasassociated with soft tissue hemagiomas May recur if incompletely excisedMay recur if incompletely excised

-Radiographic findings of enchondromas include a stippled ringlike or arclike calcifications within the lucent matrix

-Cartilage nodules can form well-circumscribed oval lucencies surrounded by thin rim of radiodensebone, the “O ring sign”

-T2-weighted MR images show lesion T2-weighted MR images show lesion with lobulated borders from endosteal with lobulated borders from endosteal scalloping and containing focal areasscalloping and containing focal areasof high signal intensityof high signal intensity

-Nuclear medicine scans usually Nuclear medicine scans usually negative in enchondromas, ruling negative in enchondromas, ruling out the possibility of malignancyout the possibility of malignancy

-Nodules of cartilage that are well-circumscribed with a hyaline matrix

-The neoplastic chondrocytes in thelacunae are cytologically benign

-Cartilage at the periphery of the nodule undergoes endochondral ossification

Giant Cell TumorGiant Cell Tumor Name derives from abundant multinucleated Name derives from abundant multinucleated osteoclast-type giant cellsosteoclast-type giant cells

Uncommon but locally aggressive tumor. Usually arises in Uncommon but locally aggressive tumor. Usually arises in patients in their twenties to forties.patients in their twenties to forties.

Giant cell tumors in adults involve both epiphyses and Giant cell tumors in adults involve both epiphyses and metaphyses, but in adolescents are confined proximally by the metaphyses, but in adolescents are confined proximally by the growth plate and are limited to the metaphysisgrowth plate and are limited to the metaphysis

Majority occur in the distal femur and proximal tibia but any Majority occur in the distal femur and proximal tibia but any bone may be involvedbone may be involved

May cause arthritic symptoms in patients or lead to pathologic May cause arthritic symptoms in patients or lead to pathologic fracturesfractures

Giant Cell TumorGiant Cell Tumor

Large red to brown tumors that undergo cystic degeneration

Giant Cell TumorGiant Cell Tumor

Conservative surgery, such as curettage, Conservative surgery, such as curettage, associated with 40% to 60% recurrence rateassociated with 40% to 60% recurrence rate

Up to 4% metastasize to the lungsUp to 4% metastasize to the lungs Some lesions can be pre-malignant or Some lesions can be pre-malignant or

malignantmalignant MRI used to determine intraarticular MRI used to determine intraarticular

extension, soft tissue involvement and bone extension, soft tissue involvement and bone marrow changesmarrow changes

Diagnostic accuracy high when MR images Diagnostic accuracy high when MR images and X-ray images are combinedand X-ray images are combined

Characteristic radiographic appearance of Characteristic radiographic appearance of

Giant Cell Tumor: multiple large bubbles Giant Cell Tumor: multiple large bubbles

separated by thin strips of boneseparated by thin strips of bone

Giant Cell TumorGiant Cell TumorTumor is composed of uniform ovalmononuclear cells with indistinct membranes and appear to grow in asyncytium

Scattered within this background are numerous osteoclast-type giant cells

Necrosis, hemorrhage, hemosiderindeposition and reactive bone formationare frequent secondary features

Aneurysmal Bone CystAneurysmal Bone Cyst

Not a true neoplasm or cystNot a true neoplasm or cyst Numerous blood filled arteriovenous Numerous blood filled arteriovenous

communicationscommunications Thought to be secondary to traumaThought to be secondary to trauma Often mistaken for malignant tumor Often mistaken for malignant tumor

on plain radiographon plain radiograph


CT can show the lobulations of the CT can show the lobulations of the lesionlesion

MRI shows internal loculation and MRI shows internal loculation and fluid levels that produce low signal on fluid levels that produce low signal on T2-weighted imagesT2-weighted images

T1-weighted images show cyst with a T1-weighted images show cyst with a low to intermediate signal intensity. low to intermediate signal intensity. Signal intensity increases if acute Signal intensity increases if acute hemorrhage presenthemorrhage present


Expansile, eccentric, cystlikeExpansile, eccentric, cystlike lesion that causes pronounced lesion that causes pronounced ballooning of thinned cortex inballooning of thinned cortex in long boneslong bones

Cystic lesion has multiple, fine Cystic lesion has multiple, fine internal septainternal septa


Microscopically, the ABC has cysticMicroscopically, the ABC has cysticspaces filled with blood. The fibrousspaces filled with blood. The fibroussepta have immature woven bone septa have immature woven bone trabeculae as well as capillariestrabeculae as well as capillarieshemosiderin-laden macrophages,hemosiderin-laden macrophages,fibroblasts, and giant cells.fibroblasts, and giant cells.

Malignant neoplasmsMalignant neoplasms

OsteosarcomaOsteosarcoma ChondrosarcomaChondrosarcoma Ewing’s SarcomaEwing’s Sarcoma

OsteosarcomaOsteosarcoma

Malignant mesenchymal tumor in which Malignant mesenchymal tumor in which cancerous cells produce bone matrixcancerous cells produce bone matrix

Accounts for approximately 20% of primary bone Accounts for approximately 20% of primary bone cancerscancers

Bimodal age distribution; 75% occur in patients Bimodal age distribution; 75% occur in patients <20 years. Second peak occurs in older adults <20 years. Second peak occurs in older adults who have known conditions associated with the who have known conditions associated with the development of osteosarcoma (Paget disease, development of osteosarcoma (Paget disease, bone infarcts, prior irradiation)bone infarcts, prior irradiation)

Metaphyseal region of long bones common site, Metaphyseal region of long bones common site, roughly 60% occur about the kneeroughly 60% occur about the knee


Patient with hereditary retinoblastomas have up to Patient with hereditary retinoblastomas have up to 1000 times greater risk of developing osteosarcoma1000 times greater risk of developing osteosarcoma

Attributed to germ line mutations in RB geneAttributed to germ line mutations in RB gene

Abnormalities in other genes that regulate cell Abnormalities in other genes that regulate cell cycling implicated (CDK4, p16, INK4A, CYCLIN D1, cycling implicated (CDK4, p16, INK4A, CYCLIN D1, MDM2)MDM2)

Typically present as painful and progressively Typically present as painful and progressively enlarging masses. At time of diagnosis, aprox. 10%-enlarging masses. At time of diagnosis, aprox. 10%-20% of patients have metastates to the lungs20% of patients have metastates to the lungs


Reactive periosteal bone formswhen tumor breaks through cortex

This leaves a triangular shadow between the cortex and raised endsof periosteum known radiographicallyas “Codman triangle”


Tan-white tumor fills most of themedullary cavity of the metaphysis and proximal diaphysis

The tumor infiltrates through thecortex, lifts the periosteum and formssoft tissue masses on the side of the bone

Several subtypes are recognized andgrouped by location, degree of differentiation, multicentricityand histologic variance

OsteosarcomaOsteosarcomaCoarse, lacelike pattern of neoplastic boneformed by anaplastic malignant tumorcells. Bone may be deposited in large sheets of primitive trabeculae

Cartilage and fibrous tissue may be presentin varying amounts. Vascular invasion usuallyconspicuous and spontaneous necrosis is common

ChondrosarcomaChondrosarcoma

Chondrosarcomas produce neoplasticcartilage

Second most common malignant matrix-producing tumor of bone

Subclassified by:Siteintramedullary, juxtacortical

Histologyconventional, clear cell,dedifferentiated, mesenchymal variant

Patients usually >40 yrs of age

Men affected twice as frequently as women

Commonly arise in central portions of skeleton: pelvis,shoulder and ribs. Clear cell variant originates in the epiphyses of long tubular bones

Often contain punctate or amorphous calcification within its cartilaginous matrix

Endosteal scalloping and cortical destruction seen radiographically

The more radiolucent the tumor, the greater likelihood of a higher grade

ChondrosarcomaChondrosarcomaTumors vary in degree of cellularity,cytologic atypia and mitotic activity

Low grade: mild hypercellularity, plump vesicular nuclei with small nucleoli, and sparse mitotic figures

High grade: extreme pleomorphismwith bizarre tumor giant cells and mitoses

Ewing’s SarcomaEwing’s Sarcoma

Small round cell tumor of boneSmall round cell tumor of bone Accounts for 6%-10% of primary Accounts for 6%-10% of primary

malignant bone tumorsmalignant bone tumors Most patients between 10 to 15 Most patients between 10 to 15

years old; youngest average age at years old; youngest average age at presentation of all bone tumorspresentation of all bone tumors

Treatment includes chemotherapy Treatment includes chemotherapy and surgical excision. At least 50% and surgical excision. At least 50% are cured long termare cured long term

Classic radiographic appearance:

Ill-defined permeative area of bone destruction

Involves large central portion of the shaft of along bone

Ewing sarcoma typically arises in the medullary cavity and invades the cortex and periosteum

Associated with a fusiform layered periosteal reaction parallel to the shaft,the classic “Onionskin appearance”

Tumor composed of sheets of uniform,small, round cells that areslightly larger than lymphocytes withscant cytoplasm

Generally little stroma and necrosis maybe prominent

Relatively few mitotic figures in relation to the dense cellularityof the tumor

ReferencesReferences

Robbins and Cotran, Robbins and Cotran, Pathologic Basis of Disease Pathologic Basis of Disease 77thth Edition Edition. Elsevier Saunders, Philadelphia, PA. Elsevier Saunders, Philadelphia, PA

Eisenberg, Eisenberg, Comprehensive Radiographic Comprehensive Radiographic Pathology 4Pathology 4thth Edition Edition. Mosby, St. Louis, MO. Mosby, St. Louis, MO

Grainger & Allison’s Diagnostic Radiology: A Grainger & Allison’s Diagnostic Radiology: A Textbook of Medical Imaging 4Textbook of Medical Imaging 4thth Edition Edition..

bone neoplasms radiographic and pathologic correlation

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