MSK neoplasms Flashcards
MC 1˚ osseous malignancies
MM/plasmacytoma (27%), OS (20%), CS (20%)
how much trabecular bone is destroyed before you can see it?
70%
what demonstrates permeative & moth eaten app?
myelin, lymphoma, ewings, OM, hyperPTH
4 main subtypes OS to know
1) conventional intramedullary (85%, higher grade than surface types)
2) parosteal (4%)
3) periosteal (1%)
4) telangiectatic (rare)
Difference btw trabecular vs cortical bone loss
Trabecular more rapidly but noticed later bc cortical bones more smooth & orgz
conventional intramedullary-1˚ vs 2˚, where, bf’s, classic met
- 1˚ 10-20 yr old
- femur (40%), prox tibia (15%)
- skip lesions, lung (occult PTX)
class OS PW
xray –> bone scan + Chest CT –> MRI (entire bone for skip lesions, bx planning) –> bx –> neoadjuvant chemo –> restage, re biopsy –> surgery –> adjuvant chemo –> f/u (2 yrs)
- re-biopsy: predicts outcome (90% tumor death = good)
- 2 yr f/u: 80% relapse –> lung. 20%–> bone
Parosteal OS
low grade, bulky/big
- pst distal femur (mimic cortical dermoid tug lesion early on )
- meatphyseal 90%
- string sign-radiolucent line sep bulky tumor from cortex.
sunburst pattern
aggressive periosteal run looks like sunburst
“reverse zoning phenomenon”
denser mature matrix in center, less peripherally (opposite of myositis ossificans)
BWs aggressive periosteal reactions
- Sunburst
- Reverse zoning phenomenon
- Lamellated
- Codman triangle
“lamellated”/onion skin rxn
multi layers of parallel peritoneum
Codman triangle
edge of raised periosteum ossifies creating appearance of triangle
parosteal vs periosteal osteosarcomas- who, where, marrow ext, grade/outcome
- Parosteal: early adult/middle age, metaphyseal, pst distal femur, marrow ext 50%, low grade, extends OUTWARD
- Periosteal: 15-25 yo, diaphysial, medial distal femur, no marrow extension, intermediate grade (worse outcome)
Telangiectatic OS-classic app
- 15% narrow zone
- Rgx: cystic
- MR: F/F levels, T1+ (methemoglobin)
Order of OS grade/outcome
Parosteal Periosteal Telangectatic Classic 2˚
Ewing’s
- 2nd MC 1˚bone malignancy in peds. ~15 yo. Rare in AA
- metadiaphysis –> diaph –> metaph
- permeative, moth eaten. +lamellated, ST 80% (Ca-)
- met –> bone (spine) (MC), lung
MC sarcoma to met to bone
Ewings
chondrosarcoma-what, RFs, where, met, matrix
- low grade tumor in older adults (40-70), M > F
- RFs: Paget’s, anything cartilaginous (OC, Maffucci), etc)
- proximal tubular bones (more abundant cartilage) & limb girdles (triradiate cartilage in pelvis)
- central (intramedullary) or peripheral (at end of osteochondroma)
- met –> lung
- “changing matrix”-vs enchondroma
chordoma
- adults 30-60 yr old
- sacrum (slightly older), clivus (slightly younger), VB (C2)
- midline, T2+++
MC 1˚ malignancy of spine
chordoma
MC 1˚ malignancy of sacrum
chordoma
where in spine does chordoma occ
VB C2
Enchondroma vs low grade chondrosarcoma-what favors chondrosarcoma?: pain, cortex, size, matrix
- Pain
- Cortical destruction (scalloping >2/3),
- > 5cm
- changing matrix
Lucent Lesions: FOGMACHINES
- Fibrous dysplasia
- OB
- GCT
- Mets
- ABC
- CB
- hyper PTH
- inf
- NOF
- Enchondroma/eusinphilic granuloma
- Simple (unicameral) bone cyst
Lucent lesions based on age
- <30 yo: EG, ABC, NOF, CB, UBC
- any age: inf
- > 40 yo: mets/myeloma (unless NB met)
Epiphyseal equivalents
- carpals
- patella
- greater trochanter
- calcaneus
Epiphyseal lesions: AIGC
- abc (after GP closes it ext from metaph)
- Inf
- GCT
- CB & clear cell CS
malignant epiphyseal lesion
-clear cell chondrosarcoma
what part of bone do mets go
metaph (greatest bs) –> diaphysis
fibrous dysplasia-what, phases, app, where
-skeletal developmental anomaly of OB-failure of normal maturation & differentiation–> repl N medullary space
- phases: lytic, mixed, blastic
- polyostotic & monoostotic (rib mc)
- long lesion, gg matrix. PR-, pain
- polyostotic: skull, face (lion-like faces); <10 yr old. mangled face, syndromic
- long bones, ribs, pelvis –> IL femur (shepherd crook deformity)
T1: heterogeneous signal, usually intermediate
T2: heterogeneous signal, usually low, but may have regions of higher signal
T1 C+ (Gd): heterogeneous contrast enhancement 4
Tc MDP+
shepherd crook
- coxa varus angulation
- FD (classic), Paget, OI
monostotic vs polyostotic FD
- monastic (20-30 yos)
- multiple lesion=<10 yr old, syndromes (McCune Albright_
McCune albright
- polyostotic FD
- Cafe Aurait spots
- precocious puberty
- girl
Mazabraud
- polyostocic FD
- ST myxoma
- (+) risk osseous malignant transformation
- middle aged F
adamantinoma-what, where, app
- v rare, low grade malignant tibial lesion
- soap bubble
- resembles FD (mixed lytic & sclerotic)
- mal pot
non ossifying fibroma (NOF), fibrous cortical defect- what, who, where, app (before regression), mx
- non-neoplastic fibrous org
- children (Rare before walking)
- knee
- app: eccentric, thin sclerotic border
- spon’t regress (more sclerotic bf disappearing)
Bone forming (osteo-) lesions
- Enostosis
- osteoma
- melorheostosis
- osteoid osteoma
- OB
- OS
Cartilage forming (Chondo-) lesions
- synovial chondromatosis/osteochondromatosis
- endochondroma
- osteochondroma
- CB
- chondromyxoid fibroma
- CS
Fibrous origin lesions
- fibroxanthomas: NOF, FCD
- Malignant fibrous histiocytoma
- FD
lesions of unknown cell org
- SBC/UBC
- ABC
- adamantinoma
lesions of vascular org
- hemangioma
- angiosarcoma of bone
lesions of hematopoietic orgn
- GCT/osteoclastoma)
- eusinophilic granuloma (Langerhands)
- Ewing sarcoma
fibroxanthomas
waste basket term for NOF (>2-3cm) & FCD (<2cm)
Jaffe-campanacci syndrome
multiple NOFs, cafe-au-lait spots, MR, hypogonadism, cardiac malformations
enchondroma
- tumor of medullary cavity composed of hyaline cartilage
- MC w/ age (peak: 10-30 yo)
-metaphysis long bones. Skull/spine spared
- app
- fingers/toes: lytic
- humerus, femur: arcs & rings
- chondroid comp = T1-, T2+ lobular lesions
- multiple? (esp hands)-syndromes: Ollier dx & maffucci syndrome
mc cystic lesions in hands/feet
enchondroma
Ollier disease
-multiple enchondromas (3+)
Maffucci syndrome
- multiple enchondromas
- hemangiomas
- greater risk CS than older
- Marfucci has More (CA & vascular malform)
syndromes ass w/ multiple enchondromas
- Ollier disease
- Maffucci syndrome
Eusinophilic granuloma/LCH
benign prol of histiocytes
- <30 yo (peak 5-10 yo)
- var appearance
- solitary (mc), mult
- lytic, blastic
- +/- sclerotic border
- +/- periosteal resp
- +/- osseous sequestrum
- bone –> skin –> CNS, HB/spleen, lungs, LN/ST, BM, SG, GI
3 classic appearances eusinophilic granuloma
1) vertebra plana
2) beveled edge
3) floating tooth w/ lytic lesion in alveolar ridge
Ddx vertebra plana (MELT)
- Mets/Myeloma
- EG
- Lymphoma
- Trauma/Tb
Ddx osseous sequestrum
OM
Lymphoma
Fibrosaroma
EG
Giant cell tumor (GCT)
- 20-30 yo; physis MUST be closed
- knee
- non sclerotic border (vs NOF), abuts articular surface
- locally invasive, pulm met (5%)
- ass w/ ABC (
osteoid osteoma-who, app, loc
- adolescent (10-25%)
- Lucent nidus surr by dense sclerotic cortical bone
- Loc
- meta/diaphysis long bone (femora neck=MC)
- pst spine (L > C > T)
associations of osteoid osteoma
- painful scoliosis, convexity pointed away from lesion
- growth deformity-increased length & girth of long bones
- synovitis- if intra-articular, JE
- arthritis- from 1˚synovitis or altered joint mechanics
“large amount of edema for size of lesion”
- osteoid osteoma
- edema can involve ST
osteoid osteoma nuclear med sign
“double density sign”-cnetral activity surr by less intense reactive bone
OO vs stress fx on nuc medicine
stress fx= linear
Rx OO-CI/relative CI
percutaneous radio frequency ablation
- can’t be w/I 2 cm of nerve or other vital structure
- typically avoided in hands, spine, pregnant pts
osteoblastoma-what, who, where
OO > 2cm
- <30 yo
- pst elements MC
- long bones 35% (diaphysis 75%)
Ddx Lucent lesion in pst element spine
OB
ABC
Met
abc-who, where, app
- 1˚ or 2˚(classically GCT, other benign lesions)
- anuerysmal lesion of bone w/ thin wall, blood filled space
- <30 yr old
- Tib > Vert> femur> humerus
- img: T2+, septal enh, F/F
solitary (unicameral) bone cyst
- CENTRAL in tubular bone
- fallen fragment sign
- <30 yo
brown tumor (hyperPTH)-what, who, where
- accumulation giant cells and fibrous tissue
- lytic or sclerotic
- subperiosteal bone resorption
- side of finger, edge of clavicle, rib
- difference stages healing/sclerosisL resorb –> sclerotic when healed
chondroblastoma-who, where, app, mx
- epiphyseal lesion 5-25 yo
- femur (greater trochanter) > humerus > tibia
- thin sclerotic rim, ext across physical plate (25-50%), periostitis (30%)
- bmarrow & ST edema-misleading for bad thing
- ONE OF ONLY TUMORS THAT”S NOT T2+
- mx-resection (reocc 30%)
chondromyoid fibroma
- rare bening cartilagenous tumor
- <30 yo
- tibia metaphysis
- osteolytic, elongated, eccentric, cortical expansion _ bite like configuration
- looks like NOF
what is special about chondroblastoma
one of only tumors that’s not T2+
least common benign lesion of cartilage
Chondromyoxid fibroma
avulsion fracture lesser trochanter
pathologic fx
pathology of intertrochanteric region
lipoma
SBC
FD (monostotic)
POEMS
rare medical syndrome w/ plasma cell proliferation (typically myeloma), neuropathy, organomegaly
- Polyneuropathy
- Organomegaly
- endocrinopathy
- M-protein
- Skin lesions
liposclerosing myxofibroma-most classic location, app, malignant degeneration
-benign fibro-osseous lesion made of a mixture of histo elements (lipoma, myxoma, myxofibroma, fibroxanthoma, FD-like features, cyst formation, ischemic ossifications, cartilage)
- intertrochanteric region
- geographic lytic lesion, sclerotic margin
-10% malignant degeneration-follow
osteochondroma/exostosis what, malignant potential (based on what?)
- cartilagenous forming developmental anomaly/tumor pointing away from joint
- MC benign tumor.
- bmarrow flows into it
- mal pot very small-cap >1.5 cm
exostosis and enostosis
- exostosis=cartilagenous forming bony protrusion
- bone island
only benign tumor associated with radiation
exostosis
multiple hereditary exostosis
AD condition w/ multiple osteochondromas
- sessile or pedunculated
- (+) risk malignant transformation
Trevor Disease/Dysplasia epiphyseal hemimelica (DEH)-what, who, where, app, mx
osteochondromas at epiphysis –> joint deformity
- ankle, knee (bad soccer players)
- young children
- cartilagenous irregular mass, point INTO joint
- mx-surgical excision
supracondylar spur (Avian spur)
- Aunt minnie, normal variant
- osseous process at medial supracondylar humerus
- point into joint
- compress median n if ligament of strutters smashes it
peripsteal chondroma (juxxta-cortical chondroma)
- rare cartilagenous lesion in finger of child
- saucerization of adj cortex w/ sclerotic periosteal rxn
osteofibrous dysplasia
- developmental tumor-like, fibroosseous condition
- benign lesion in tib/fib of child <10 yo
- spon’t regression
-almost exclusively in ANT TIB DIAPH
- ant tibial bowing
- char sclerotic band
- can occ with adamantinoma, looks like NOF
-indis from NOF, FD, adamantinoma
NOF in anterior tibia w/ anterior bowing
osteofibrous dysplasia
distal femoral metaphyseal irregularity/cortical desmoid-what, where, mx, Mao, bw
- lucency at pst lat distal femoral metaph (BL).
- incidental- Do not touch. No further img
- BW: “scoop like defect”
- likely MOA: chronic tug lesion from adductor magnus
“scoop like defect”
distal femoral metaphyseal irregularity/cortical desmoid
most pathologic calcification in the body
calcium hydroxyapatite
most abundant form of calcium in bone
calcium hydroxyapatite
calcific tendinitis
-Ca hydroxyapatite deposition disease. 1˚or 2˚
MC locs calcific tendinitis
- MC=supraspinatus tenon at insertion near greater tuberosity
- longus colli m (ant to atlas–> T3)
2˚ causes calcific tendinitis
- chronic renal dx
- collagen vascular dx
- tumoral calcinosis
- hypervitaminosis D
osteopoikilosis
- mult bone islands in epiphyses
- inherited (AD) or sporadic
- joint centered (vs mets)
- keloid formers
osteopathic striata
- linear, parallel and long lines in metaph of long bones
- +/- pain
engelmann’s disease/progressive diaphysial dysplasia (PDD)
- fusiform bony enlargement + sclerosis long bones
- childhood
- BL, symmetric
- bone scan hot
- loc
- tibia-MC
- skull –> optic n compression
thalassemia vs sickle cell
Thalassemia will obliterate sinuses, SCD will not
thalassemia buzzwords
- hair on end
- rodent faces
- jail bars
Causes AVN hip
Perthes
- SCD
- Gaucher’s
- steroids
- trauma (femoral neck fx-degree of risk related to degree of displacement & disruption reticular less’)
where does avn hip usually start
superoant articular surface
double line sign AVN hip
inner T2+ (granulation tissue) + outer dark (sclerotic border)
rim sign AVN hip
T2+ sandwiched btw two T2(-)=fluid btw sclerotic borders of osteochondral fragmentation ==> instab
crescent sign AVN hip
Xray subchondral lucency in anterolat aspect of proximal femoral head. indicates imminent collapse
plain film stages osteonecrosis
0=N 1= Xray N. MRI edema 2= mixed lytic & sclerotic 3= crescent sign, articular collapse, joint space preserved 4= 2˚ OA
Paget’s dx/osteitis deformans-incidence, epidemiology
- 4% at 40, 8% at 80
- M > F
paget’s 3 phases
1) lytic
2) mixed (reparative)
3) sclerotic (latent inactive)
“wide bones with thick trabecular”
paget’s
sgx’s and syx’s ass w/ paget phases
1) lytic-usually asyx
2) mixed (reparative)- ALP+ 20x, fx
3) sclerotic-hydroxyproline+, fx+, sarcomas
blade of grass sign
Paget’s. Lucent leading edge in a long bone
osteoporosis circumscripta
Paget’s. Lucent leading edge in frontal/occipital skull
picture frame vertebra
Paget’s. Cortex expanded on all sides
Cotton wool bone
Paget’s. Thick disorganized trabeculae
Banana fracture
Paget’s. Insufficiency fx of bowed soft bone (femur or tibia)
tam o’shanter sgx
Paget’s. Thick skull w/ front aspect “falling over the facial bones”
Saber shin
Paget’s. Bowing of tibia.
Ivory vertebra
Paget’s & mets. Pagets=expansile
Paget’s complications
Deafness-mc
- spinal stenosis-characteristic
- cortical stress fx
- CN paresis
- CHF (high output)
- 2˚hyperPTH (10%)
- 2˚OS (1%), GCT
paget’s on bone scan
hyper vascular, 5˚ hotter than other bone
what part of skull does Paget’s involve
inner and outer tables (vs FD)
MC bone involved in Pagets. Compl’s
Pelvis
- always involves iliopectineal line on pelvic brim
- 2˚ OA, acetabular protrusion
- classic look on scan
rugger jersey spine
top and bottom VB
-renal osteodystrophy, oteopetrosis
osteopetrosis
genetic dx w/ impaired osteoclastic resorption
- thick cortical bone w/ diminished marrow
- rugger jersey or sandwich vertebra
- dark T1 (loss of normal marrow)
“widening of disc space” aka
“h-shaped vertebrae”
Paget’s different phases MRI appearance
1) lytic/eary mixed-T2 hetero. T1 iso w/ speckled app
2) late mixed-T1/2+ (fatty)
3) sclerotic-T1/2-
Paget active dx vs malignant transformation
- loss of T1 signal w/ cancer
- both T2+, enh
paget’s nuclear medicine
-hot on all 3 phase bone scan
Why are soft tissue masses not accurately diagnosed on MRI?
20-30% bc almost all are T2+, enh
soft tissue masses to know
- Malignant fibrous histiocytoma (MFH)
- synovial sarcoma
- lipoma, atypical lipoma, liposarcoma
- hemangioma
- myxoma
malignant fibrous histiocytoma/pleomorphic undifferentiated sarcoma-who, where, app, ass, RFs
Undifferentiated pleomorphic sarcoma (UPS), previously known as malignant fibrous histiocytoma (MFH), is considered the most common type of soft tissue sarcoma. It has an aggressive biological behavior and a poor prognosis.
- older
- central loc (proximal arm & leg)
- T2- (50%) (“fibrous”
- spon’t hem (outgrow bs)
- 2˚=bone infarcts, radiation
“sarcomatous transformation of infarct”
malignant fibrous histiocytoma (MFH)/Pleomorphic undifferentiated sarcoma (“pus”)
synovial sarcoma-who, where, img, translocation
- 20-40 yos (mc malignancy in teens/young adults of foot/ankle/LE)
- translocation of X18 (90%)
- peripheral LEs, close to joint; foot, ankle, LE (knee)
- 2˚ invasion into joint (10%)-just remember they never involve joint
- img: small (slow growing), ST mass, Ca+, bone erosion
- triple sign-T2 high, medium, low signal in same mass (probably at knee)
- bowl of grapes-fluid levels in mass (probably in knee)
- xray ST mass + Ca
synovial sarcoma vs baker’s cyst
sarcoma. ..
- complex
- blood flow
Synovial sarcoma vs other sarcomas
attacks bone, causes pain
“ball like tumor” in extremity of young adult
synovial sarcoma
ST tumor in food of young adult
synovial sarcoma
MFH (PUS) vs synovia sarcoma
- MFH-old, central, T2 variable
- SS-young, per, T2 triple sign
MC liposarcoma <20 yo
myxoid liposarcoma
spectrum fat containing ST masses
lipoma –> atypical lipoma –> liposarcoma
lipoma vs atypical lipoma/low grade liposarcoma vs high grade liposarcoma
- lipoma-Super. Completely fat sat, no sept
- AL/LGL- may incomp fat sat, thick chunky sept
- HGL- Deep. Incompl/no fat sat/, thick nodular complex enhancing content. +/- fat. Deep
T/F: hemangiomas respect fascial boundaries
false
mazabraud syndrome
- polyostotic fibrous dysplasia
- mult ST myxomas
myoma
T2+, T1-
-ass w/ mazabraud syndrome
mx GCT
arthroplasty (bc ext to articular surf)
pigmented villonodular synovitis (PVNS)-what, who, where, app, rx, recurrence rate
- small nodules lining synovium, synovial proliferation + hemosiderin dep (via tendency to bleed)
- adults (polyarticular in kids)
- focal or diffuse
- intraarticular, knee 65-80%
- osseous erosion w/ preservation of joint space and normal mineralization
- tendency to bleed –> hemosiderin –> blooming, low sign
- T1/T2(-), blooming
- (+) large hemorrhagic joint effusion
- Ca (late)
- rx=synovectomy
- recurr 20-50%
GCT of the tendon sheath/PVNS of the tendon
hand (palmar)
2nd MC ST mass of hand/wrist (after ganglion)
- T1/T2(-)
- diffusely/avid enh
-vs glomus tumor: T1(-), *T2+, enh
1˚ synovial chondromatosis
- 1˚ or 2˚(from OA). Non-inflamm metaplastic/true Neo
- mult cartilaginous nodules in synovium of joints, tendon sheaths, bursae–> loose bodies. +/- Ca
- knee (70%)
- 40s-50s
- rx-removal LBs +/0 synovectomy
PVNS vs synovial chondromatosis
- PVNS-hemarthosis, never Ca
- SC-no hemarthosis, +/- Ca
1˚ vs 2˚ synovial chodnromatosis
2˚ loose bodies fewer, larger; extensive degen
diabetic myonecrosis-who, where, app, bx?
- muscle infarction in poorly controlled DM 1
- thigh (80%), calf (20%)
- edema, enh, irregular m necross
- no bx-delays recovery, compl++
lipoma arborescents
frond-like depo fatty tissue in synovial lining of joints, bursa
- suprapatellar bursa knee. Normal knee or ass w/ OA, chronic RA, trauma. UL
- 50-70s
- img=fat
tumoral calcinosis
- Hereditary phosphate metabolism (Ca normal, P isn’t.)
- big lobular/cystic Ca near joint.
- Layering fluid/Ca levels. No erosion/destruction joint.
- Hip (greater trochanteric bursa), elbow, shoulder (knee rare)
tumoral calcinais vs metastatic Ca
look sim but labs different
what to avoid when biopsying pelvis
-gluteal m’s (may need for reconstruction)
what to avoid when biopsying knee
- crossing joint space via supra patellar or other communicating bursae
- quadriceps tendon (unless involved)
what to avoid when biopsying shoulder
pst 2/3 (axillary n courses pst –> ant== may denervate ant 1/3 of nerve)
don’t touch lesions
- myositis ossificans
- avulsion injury
- cortical desmoid
- synovial herniation pit (“Pitt’s pit)
synovial herniation pit (“Pitt’s pit)
lytic appearing lesion ass w/ femoral acetabular impingement syndrome
metastatic Ca
- MOA=hypercalcemia
- fine and diffuse ST Ca + renal/lung Ca
non ossifying fibroma aka
fibrous cortical defect
fibroxanthoma
mx NOF
curettage and bone graft-if indicated (ex: patho fx)
chondroid matrix
Calcifications in chondroid tumors have many descriptions: rings-and-arcs, popcorn, focal stippled or flocculent.
osteoid matrix
trabecular ossification pattern in benign bone-forming lesions and as a cloud-like or ill-defined amorphous pattern in osteosarcomas.
plasmacytoma
proliferation of plasma cells
-lytic lesions + ST mass
myxoma
- intramuscular tumor, mc in thigh, butt, shoulder girdle
- char T2+, T1 (-)/~
- hypointense sept, nods
- hetero enh
Gorham disease/ Gorham massive osteolysis/ gorham-stout syndrome/ disappearing bone disease
- rare vascular disorder of lymphatic etiology
- bone resorption + ST change at skel site + splenic cysts
Bone:
- spon’t, progressive resorption of bone
- MC=skull, shoulder, pelvis
- usually single bone –> regional (no regard for boundaries)
- hx trauma
- +patho fx
-splenic lesions/cyst
ST change at site of skeletal involvement
plantar fibromatosis
- fibroblastic and myofibroblastic tumor
- plantar fascia of foot, BL 20-50%
- M>F
MR:
- T1 (-)/~
- T2 hetero
- enh+ hetero
-US: hetero hypoecho
paraosteal osteochondromatous proliferation/ “Nora lesion”
- rare, exophytic growths from osseous cortical surfs,
- bone, cartilage & fibrous tissue
- post reparative vs benign neoplastic
parosteal osteosarcoma vs myositis ossificans
- PS: centrally most dense
- MO: peripherally most dense
telangiectatic OS vs ABC
OS:
1) thick nodular separations, surrounding ST comp (best demonstrated on contrast+ CT or MRI
2) matrix mineralization in the lesion
3) aggr fx’s, ex: cortical destruction
glomus tumor
benign sublingual tumor (hamartoma) developing from neuromyoarterial gloms bodies)
- T2+, T1-, richly vascular (MRI/MA)
- mx- surgical excision (complete resolution of syx’s after!)
patellar lesions
- end of bone
- benign (usually)
-CB –> GCT
sclerotic MM ass
rare
-ass w/ POEMS
periosteal chondroma/ juxtacortical chondroma
- benign cartilage tumor arising on surface of bone deep to periosteum
- metaph of long bones
- saucerization of cortex, sclerotic margination, dense periosteal rxn
- +matrix
-T1, T2- (chondroid composition)
hemangiopericytoma/ solitary fibrous tumor
- heterog group of benign and malignant spindle cell neoplasms
- staghorn branching pattern
- hypoglc and osteomalacia
bx shoulder lesion
ant
bx prox tvb metaph
ant med
Pannus Rheumatoid Arthritis
synovial inflammatory mass posterior to C2 and surrounding the dens in association with odontoid erosion.
Typical patient age range for tumors
<20 yo
20-40
40
typical skel loc descriptors for tumors
- flat vs tubular
- epiphyseal vs metaphyseal vs diaphyseal
- medullary vs cortical
True of false: the margin of lesion and type of periosteal reaction indicate benign vs malignant
False. It indications lesion aggression
Bone lesions with age predilection <20: benign & mal
Benign:
- fibrous cortical defect, NOF, SBC, ABC
- LCH
- OB, OO
- osteofibrous dysplasia
- chondromyxoid fibroma
- fibrous dysplasia
- enchondroma
Malignant:
- leukemia, ES, HL
- OS (conventional, periosteal, telangiectatic.)
- mets (rare)
- NB, RB
- rhabdomyosarcoma
Bone lesions with age predilection 20-40: benign & mal
Benign:
- enchondroma
- GCT
- OB, OO
- chondromyxoid fibroma
- FD
Mal:
- OS (periosteal)
- adamantinoma
Bone lesions with age predilection >40: benign & mal
Benign:
- FD
- Paget disease
- NHL
- chondrosarcoma
- malignant fibrous histiocytoma
- osteosarcoma (secondary to Paget disease and radiation)
Mal:
- mets (MC)
- MM
The specific radiographic features that should be evaluated
tumor location, margins and zone of
transition, periosteal reaction, mineralization, size and number of lesions, and presence of a soft-tissue component.
the most important piece of clinical information
when assessing a bone tumor
age
why does OS have predilection for metaph and why does ES have predilection for red marrow?
some tumors (eg, osteosarcoma) have a predilection for sites of rapid bone growth, usually the metaphyseal region, while other tumors (eg, Ewing sarcoma) tend to follow the distribution of red marrow
Apophysis
(a growth center that
does not contribute to the length of a
bone) is the equivalent of an epiphysis
Describing margins
Focal & discrete=
Type 1= “geographic”
-1a-well defined border with sclerotic rim
-1b-focal lytic lesion with ill-defined border
Infiltrative=
- Type 2: “moth-eathen”
- Type 3: “permeative”
-from least to most aggressive appearing
benign but aggressive appearing lesions
OMS
LCH
well defined margin but mal
GCT
Why are they called “ small round blue cell group”
histologic appearance on hematoxylin and eosin stained specimens
*OM and LCH also look “blue”
classic “permeative” lesions
small round blue cell grp (ES, lymphoma)-small enough to fit through the haversian canals
patterns of periosteal rxn
1) solid, unilamellated- nonaggressive.
- Slow growing allowing bone to wall it off
2) multilamellated (onionskin)-intermediately aggressive
- Wax & wane such that bone continually trying to wall off but cannot.
3) Interruption (regional disruption)-aggressive
- Has broken through the periosteum
4) spiculated, hair-on-end (T to cortex), sunburst-most aggressive
codman triangle-what, what lesions
- elevation of periosteum away from cortex with angle formed where elevated periosteum and bone come togehter
- conventional OS
- inf, subperiosteal hematoma
How does sequestrum form
diestructive process caues fragment of bon e(sequestrum) to become stuck in lytic region
trabecular patterns of:
- ABC, desmoplastic fibroma
- PD
- hemangioma
- ABC, DF: honeycomb
- PD: coarse
- hemangioma: Sunburst/spoke-and-wheel in long bone. “Corderoy” (vertically oriented, coarsened) in VB
matrix
type of tissue of tumor:
- osteoid
- chondral
- fibrous
- adipose
mineralization
calcification of matrix
mineralized chondral tissue/cartilate
punctate, flocculent, comma-shaped, arclike/ringlike
mineralization of bone
fluffy
amorphous
cloudlike
mets vs osteopoikolosis
OPK=same size, centered around joints
mult lytic lesions >40 yo
- mets
- mm
- NHL
- brown tumors
pathophys of lytic expansile/”soap bubble” appearanc
slow growing medullary process grows outward but bone has time to lay down new periosteum
endosteal scalloping vs saucerization
- Endo scall: in to out
- sauce: out to in
tumors with ST components
- OS
- ES
- lymphoma
“end of bone” sites
- epiphyses
- aphophyses
- patella
- sm bones of wrist
- mid/hindfoot
- subarticular portions of flat bones (SI joints, acetabuli, glenoid)
Specific sites for tumors:
- adamantinoma, OFD
- epidermal inclusion cyst, glomus tumor
- periosteal desmoid, parosteal OS
- chordoma
- hemangioma
- SBC, intraosseous lipoma
- OB, ABC
- adamantinoma, OFD: tib ant cortex
- epidermal inclusion cyst, glomus tumor
- periosteal desmoid, parosteal OS-pst cortex of distal femur
- chordoma-clivus, VB, sacrum
- hemangioma-VB
- SBC, intraosseous lipoma-calcaneus
- OB, ABC-pst elements of spine
Specific sites for tumors:
- adamantinoma, OFD
- epidermal inclusion cyst, glomus tumor
- periosteal desmoid, parosteal OS
- chordoma
- hemangioma
- SBC, intraosseous lipoma
- OB, ABC
- adamantinoma, OFD: tib ant cortex
- epidermal inclusion cyst, glomus tumor
- periosteal desmoid, parosteal OS-pst cortex of distal femur
- chordoma-clivus, VB, sacrum
- hemangioma-VB
- SBC, intraosseous lipoma-calcaneus
- OB, ABC-pst elements of spine
