Bone Tumors Flashcards
Types of periosteal reaction?
benign: solid periosteal reaction
aggressive: lamellated, sunburst, codman triangle
Patterns of bone destruction?
zone of transition
geographic pattern: thin zone of transition, sclerotic or well defined
moth-eaten: difficult to define a border, aggressive
permeative: multiple tiny holes that infiltrate bone (lymphoma, leukemia, Ewing)
Matrix types of tumor
osteoid: fluffy, cloud like (malignant osteosarcoma)
chondroid: ring/arc or popcorn (enchondroma, chondrosarcoma)
ground glass: fibrous dysplasia, blurring of trabeculae
fallen fragment sign
simple bone cyst; pathologic fracture
aneurysmal expansile feature
ABC
resorption of distal clavicles/tumoral calcinosis
hyperparathyroidism (brown tumors)
<20 yo, bone tumor?
>40yo, bone tumor?
aggressive <20; eosinophilic granuloma/LCH, infection, Ewing
aggressive > 40; myeloma, mets
Eccentric bone lesions
giant cell tumor, chondroblastoma, ABC, NOF, chondromyxoid fibroid (rare)
Central bone lesions
simple bone cyst, enchondroma, fibrous dysplasia
small spiculated osteoblastic focus
enostosis/bone island; arises from medullary canal
Osteopoikilosis
AD syndrome of multiple bone islands and keloid formation
Osteoma?
Associated syndrome?
cortex of skull or frontal/ethmoid sinuses ; rises from cortex
Gardner syndrome: AD of multiple osteomas, intestinal polyposis, soft tissue desmoid tumors
Melorheostosis
pain, decreased ROM, leg bowing, leg-length discrepancy
single lower limb in single sclerotome
Hallmark of melorheostosis
thickened, irregular cortex with “candlewax” appearance
increased uptake bone scan
Presentation osteoid osteoma
night pain relieved by aspirin in teen/young adult; long bones common
osteoid osteoma
nidus of osteoid tissue surrounded by reactive bone sclerosis; osteoblastic
Double density sign
uptake centrally in nidus and adjacent reactive uptake/sclerosis
Hallmark of osteoid osteoma
lucent nidus with sclerosis
Treatment osteoid osteoma
radiofrequency ablation, surgical curettage, resection
Osteoblastoma vs osteoid osteoma
osteoblastoma >2cm
much less common than osteoid osteoma (4x less) and pain is not relieved by aspirin
common location for osteoblastoma?
posterior elements of the spine
Ddx posterior element lytic lesion
osteoblastoma vs aneurysmal bone cyst;
favor osteoblastoma is there is mineralization
osteosarcoma, primary and secondary
primary osteosarcoma: neoplastic cells from osteoid lineage
secondary: Paget disease (extremely aggressive)/after radiation
Major subtypes of osteosarcoma
conventional (most common), telangiectatic, juxtacortical types (parosteal and periosteal)
Conventional/intramedullary osteosarcoma
most common type; adolescents/young adults, around knee or metaphysis femur/tibia
Telangiectatic osteosarcoma
osteolytic destructive sarcoma, may mimic ABC
vascular with large cystic spaces filled with blood
Parosteal osteosarcoma
arises from outer periosteum; posterior aspect of femoral metaphysis with cauliflower like exophytic morphology
patients in their 20-30s; least malignant type
Periosteal osteosarcoma
inner periosteum; cortical thickening, aggressive periosteal reaciton, soft tissue mass
younger patient 20s; commonly diaphysis of femur/tibia
osteosarcoma mets?
commonly to lung; where they calcify
synovial chondromatosis , osteochondromatosis
monoarticular; intra-articular lobulated cartilaginous nodules –> calcification (osteochondromatosis)
common location for synovial chondromatosis
knee; shoulders/hip/elbows may also be affected
rarely may degenerate into chondrosarcoma
Hallmark of synovial chondromatosis
XR: round intra-articular bodies of similar size/variable minerzalization (ddx intraarticular bodies from OA)
MR: globular/rounded foci of low signal (ddx PVNS)
Enchondroma
benign lesion of mature hyaline cartilage rests; popcorn or ring/arc calcifications ; hyperintense lobulated appearance on T2
ddx for enchondroma
medullary bone infarct (serpentine sclerosis) and chondrosarcoma
enchondroma in the hand
geographic lytic lesion
Ollier vs Maffucci syndrome
Ollier: multiple enchondromas
Maffucci: multiple enchondromas and phleboliths
increased risk of malignant degeneration into chondrosarcoma (Maffuci more)
most common benign bone lesion
osteochondroma; benign cartilage cap projecting outward from bone
signs of malignant transformation of osteochondroma to chondrosarcoma
- pain in the absence of pathologic fracture
- associated soft tissue mass
- cartilage cap >2 cm
syndromes with osteochondroma
familial osteochondromatosis/multiple hereditary exostoses (autosomal dominant)
commonly affects knees
chondroblastoma
benign; long bone epiphysis of pediatric patients (knees, proximal humerus)
chondroblastoma treatment
curettage, cryosurgery, radiofrequency ablation
chondroblastoma MR findings
low/intermediate T2 weighted images
chondromyxoid fibroma
eccentric in tibial/femoral metaphysis about knee; sclerotic margins and high T2 signal
malignant tumor of cartilage?
chondrosarcoma
Primary and secondary chondrosarcoma
Primary: conventional/intramedullary chondrosarcoma ; dedifferentiated, rare mesenchymal, clear cell variants
Secondary: enchondroma degeneration, Paget, osteochondroma
NOF or fibroxanthoma
radiolucent long bone lesion (leg) in children/adolescents
believed to arise from periosteum?
alt name for malignant fibrous histiocytoma (MFH)
undifferentiated pleomorphic sarcoma not otherwise specified
most common adult soft tissue sarcoma
MFH; middle aged adults in thigh/retroperitoneum
Fibrous dysplasia patients
non neoplastic condition of children/young adults ; congenital!
may result in pathologic fracture (femoral neck); shepherd’s crook
Fibrous dysplasia patterns
- femur
- ribs/long bones
- pelvic bones
- skull base
- varus deformity, shepherd’s crook
- indistinct/ground glass
- cystic
- expansile
Ddx for expansile skull base lesions
pediatrics: fibrous dysplasia
adults: Pagets
fibrous dysplasia congenital lesions
McCune Albright: polyostotic fibrous dysplasia, precocious puberty, cutaneous cafe au lait spots
Mazabraud syndrome: fibrous dysplasi and intramuscular myxomas
Radiographic signs associated with hemangiomas
corduroy appearance/striations
polka-dot sign of thickened trabeculae in cross- section
MR: high T1/T2 signal
bone hemangioma
occurs in vertebral body; vascular channels lined by endothelial cells ; may have soft tissue mass
angiosarcoma bone
clustering of multifocal lesions in single anatomic region
lung mets
Age for osteoclastoma/giant cell tumor
20-40s
Location of giant cell tumor
eccentrically at articular ends; arises from metaphysis and involves epiphysis
LCH demographic
5-10yo kids
Hallmarks of LCH
beveled edge skull
floating tooth in madible/maxilla
vertebra plana
Ewing sarcoma age?
children/adolescents; male predominance
second most common after osteosarcoma
Ewing sarcoma appearance
aggressive lesion with permeative bone destructive, aggressive periosteal reaction, soft tissue mass
Ddx for ewing sarcoma
osteomyelitis, eosinophilic granuloma (LCH), metastatic neuroblastoma
Multiple myeloma age
> 40; most common primary malignant bone tumor
Presentation multiple myeloma
multiple lytic lesions; diffuse myelomatosis with endosteal scalloping
POEMS syndrome? association?
polyneuropathy, organomegaly, endocrine disturbances, monoclonal gammopathy, skin changes
association: sclerosing myelomatosis
Ddx for multiple lytic lesions
metastatic disease, multiple myeloma (doesn’t involve posterior elements)
Solitary multiple myeloma met
plasmocytoma –> MM in 5 years
primary bone lymphoma age?
> 40; consider with ivory/sclerotic vertebral body
Bone lipoma sites
calcaneus, sutrochanteric region of femur, distal tibia/fibula, metatarsals
Imaging considerations with bone lipoma
may contain some nonadipose tissue
Liposarcoma imaging findings
> 10 cm, thick septations, globular/nodular soft tissue; <75% fat
Chordoma
malignant lesion from notocord remnant from axial skeleton; sphenooccipital region, body of C2, or sacrococygeal location
Chordoma imaging features
destructive lesion with irregular scalloped borders; calcifications due to necrosis
Bone cyst imaging locations
hollow/fluid filled lesion in proximal humerus/femur; calcaneus, iliac bone/tibia
age for simple bone cyst
children/adolescents
Imaging findings for simple bone cyst
no periosteal reaction; fallen fragment sign (if pathologic fracture), located centrally in bone, fluid levels on MRI
ddx fluid levels in bone cyst
ABC, bone cyst, giant cell tumor, telangiectatic osteosarcoma
Treatment for bone cyst
inject methylprednisolone
ABC histology
blood filled sinusoids and solid fibrous elements; may be secondary to pre-existing tumor
ABC age and location
expansile lesion anywhere in bone and posterior elements of spine; children/adolescents
Adamantinoma?
soap bubble lesion in the tibia; similar to fibrous dysplasia; very rare
solitary sternal lesion?
breast cancer mets
fracture of lesser trochanter?
think pathologic fracture from mets
pedicle/posterior vertebral body fracture
metastases
Lytic lesions/mets
lung, breast, thyroid, kidney, stomach/colon
Sclerotic lesions/mets
breast, prostate/seminoma, TCC, mucinous tumors, carcinoid
Myositis ossificans?
heterotopic bone formation in muscle usually secondary to trauma; commonly elbow/thigh
How to differentiate from myositis ossificans and parosteal osteosarcoma?
osteosarcoma more heavily calcified centrally
myositis ossificans calcified more peripherally
Do you biopsy myositis ossificans?
no; unnecessary surgry as it may resemble sarcoma
Evolution of myositis ossificans
Week 1-2: soft tissue mass
Week 3-4: amorphous osteoid matrix; periosteal reaction of bnoe may mimic early osteosarcoma
Week 5-8: periphery of lesion matures into compact bone
6 mo: ossification matures
What is brown tumor?
lytic lesion seen in hyperparathyroidism (increased osteoclast activation); osteopenia, subperiosteal bone resorption, soft tissue calcifications
rugger jersey spine
osteodystrophy
