Chrondrogenic tumours Flashcards
Enchondromas periosteal chondromas Osteochondromas & mutliple hereditary exostois Chondroblastoma Chondromyxoid fibroma Chondrosarcoma
1
Q
what is an enchondroma?
A
- A Benign chrondrogenic tumour- 2nd most common
- composed of Hyaline cartilage
- caused by abnormality in chondrocyte function in the physis
- M=F
- most common 20-50 yrs
- usually in medullary canal in diaphysis and metaphysis
- most common in hand 60%
-
location
- distal femur, proximal humerus,tibia
- rare in spine/pelvis
2
Q
What is the pathophysioogy of enchondroma?
A
- enchondromas represent incomplete endochondral ossification
- chondroblasts and fragments of epiphyseal cartilage escape from the physis, displace into the metaphysis and proliferate there
3
Q
Name associated conditions of enchondromas?
A
- Solitary enchondromas
-
Ollier’s disease
- multiple enchondromatis
- no genetic predisposition
- skeletal dysplasia with failure of normal endochondral ossification
- enchondromas throughout the metaphyses and diaphyses of long bones
- involved bones are dysplastic, with shortening and bowing
- risk of malignant transformation <30%
-
Maffucci syndrome
- sporadic inheritance
- multiple enchondromas & soft tissue angiomas
- risk of malignancy 100%
- increased risk of visceral malignancy
4
Q
Can you describe the enneking staging of benign lesions?
A
- Grade 1- Latent lesion-= enchondroma, non ossfiying fibroma
- Grade 2- Active lesion =ABC/UBC/Chondroblastoma
- Grade 3- Aggressive lesion = GCT
5
Q
Describe the symptoms and signs of enchondromas?
A
Symptoms
- asymptomatic- found incidentially- tibia
- pathologcial fx- hand
-
Pain - uncommon
- most chondrosarcomas have non mechanical pain
Signs
- Angular deformity and shortening
- blusih angiomas of maffucci
6
Q
What is seen on xrays of enchondromas?
A
- pop corn stippled calcification & rings
- bone expansion
- Lytic in hand
- in Maffucci = angiomas are visible as calcified phleboliths
7
Q
How are chondrosarcomas different from enchondromas?
A
- unlike enchondromas, chondrosarcomas display
- cortical thickening and destruction
- endosteal erosions and scalloping >50% of the width of the cortex
are larger (>5cm)
8
Q
Describe the histology in enchondromas?
A
- hypocellular with bland, mature hyaline cartilage (blue balls of cartilage) separated by normal marrow
9
Q
Describe the tx of enchondromas?
A
- non operative
-
observation
- majority
- with serial xrays in 3-6months for 1-2 years
- long term FU with multiple enchondromas
-
observation
-
Surgery
-
intralesional curettage & bone graft
- lesions that show any change in lesion
-
immobilisation, currettage & bone graft
- path fx
- immobilisatio until union then currettage & BG
-
intralesional curettage & bone graft
10
Q
What is periosteal chondroma?
A
- A rare type of chondroma - benign
- occurs on surface of long bones
- under periosteum of distal femur,prox humerus and prox femur
- 59% prox humerus
- 10-20 yrs old
11
Q
what are the symtpoms of periosteal enchondromas?
A
-
Pain
- 2ary to irriation from tendons
12
Q
What is seen on radiographs with periosteal enchondromas?
A
- saucerization of underlying bone
- punctate mineralisation in 1/3
- well demarcated, shallow cortical defects
13
Q
What is seen on histology of periosteal enchondromas?
A
- Bland hyaline cartilage
- small chondroid cells in lacunar spaces
14
Q
What is the tx of periosteal enchondromas?
A
- Operative
- marginal excision including underlying cortex
- if symptoms intereferring with function
- lesion with reoccurif cartilage is left behind
15
Q
What is an osteochondroma & multiple hereditary exostosis?
A
- A Benign chrondrogenic lesion derived from aberrant cartilage from the periochondral ring that may take the form of
- solitary osteochondroma
- Multiple hereditary exostosis ( MHE)
- Most common Benign bone tumour
- Many asymptomatic
- common adolescents/young adults
- location on surface of bones, often at sites of tendon insertions
- knee
- prox femur
- prox humerus
- sugungal exostosis- at hallux
- Autosomal Dominant
- Mutation in EXT gene affects prehypertrophic chondrocytes of growth plate
16
Q
What are the associated conditions of osteochondroma & multiple hereditary exostosis?
A
-
Secondary Chondrosarcomas
- a malignant condition that results from malignant transformation of solitary osteochondromas or MHE
- occurs older pts - 50 yrs
- most common location is the pelvis
17
Q
What is the prognosis of osteochondroma & multiple hereditary exostosis?
A
- Risk of malignant change
- <1% solitary osteochondromas
- 5-10% in multiple hereditary exostosis develop secondary chondrosarcomas
18
Q
Define multiple hereditary extosis
A
- Disorder characterised by multiple osteochondromas
- mutation affects the prehypertrophic chondrocytes of the physis
- Autosomal Dominant
- mutations in EXT1 ,EXT2, EXT 3 genes = tumour suppressor genes
-
ext1 individuals > severe presentation cf EXT 2 mutations
- higher rate of osteosarcomas
- more exostoses
- more limb malignment
19
Q
What is the prognosis of MHE?
A
- 5-10% malignant change to chondrosarcomas
- proximal lesions more likely to undergo malignant transformation than distal lesions
20
Q
What are the symptoms of osteochondromas?
A
- most asymptomatic
- painless mass
- NV compromise
- mechanical symptoms
21
Q
What are the symptoms of MHE?
A
Limb deformities
- femoral shortening & LLD
- coxa Valga
- knee valgus- shortened fibular, patella dislocation
- ankle valgus- shortened fibular
- upper limb- ulna shortening, radial head dislocation/radial bowing
- nay increase in acute apain should raise suspicion of malignancy
22
Q
What is seen on radiographs with osteochondromas & multiple hereditary exostosis?
A
- Sessile ( broad base)
- Pedunculated ( narrow stalk)
- found on surface of bones
- >malignancy risk in sessile lesions
- pedunculated point away from joint
- cortex of lesion continous w cortex of native bone
- medullary canal of lesion continous w medullary cavity of native bone
23
Q
What is the histology of osteochondroma & multiple hereditary exostosis?
A
- similar to normal physis with
- cartilage cap consisting of hyaline cartilage
- normal primary trabeculae
- linear clusters of active chondrocytes
- may have thin cartilage cap covering the lesion
24
Q
What is the tx of osteochondroma
A
- Non operative
-
Observation
- asymptomatic
-
Observation
- Surgery
-
Marginal resection at base of stalk including cartilage cap
- symptomatic lesions
- delay surgery until skeletal maturity
-
Marginal resection at base of stalk including cartilage cap
25
What is the tx of multiple hereditary exostosis?
* non operative
* **observation**
* most don't require intervention prior to reaching skeletal maturity
* Operative
* **Surgical excision of osteochondromas**
* if dislocation of radial head
* loss of forearm rotation
* optimises chances of improved motion
26
tx of secondary chondrosarcomas
* Operative
* **wide surgical resection**
* tx as typical condrosarcoma
27
what are the complications of osteochondroma & multiple hereditary exostosis?
* **Pseudoaneursym of popliteal artery**
* **nerve compression**
* ****sciatic/common peroneal n, radial n
* **tendon compression**
* **Chondrosarcoma**
* in adults **cartilage cap \>2cm** assoc with increased risk of malignancy
* mean age of dx 31yrs
* **Bursa formation**
* **reocurrance**
* 2-5% post resection
28
What are the differential dx of a surface lesion?
* Osteochondroma/ MHE
* Periosteal chondroma
* Parosteal osteosarcoma
* Periosteal osteosarcoma
29
Define chondroblastoma?
* A **benign chondrogenic lesion**
* differs to **GCT by chondroid matrix**
* 2:1 male/female
* most pts \<25yrs
* location= **Epiphyseal lesion in young pts**
* apophysis/ distal femur/ prox tibia/ prx humerus/prox femur
* Typically **epiphyseal** but **may cross Physis**
* **chromosome abnormalities 5/8**
30
What is the prognosis of chondroblastoma?
* **1-2%** benign chondroblastoma **metastasise to lungs**
* similar to GCT
* reocurrance **10-15%** post surgicla resection
31
what are the symptoms of chondroblastoma?
* Increase pain in involved joint
32
what is seen on xrays with chondroblastoma?
* Well circumscribed **epiphyseal lytic lesion**- thin rim of sclerotic bone that is sharply demarcated from normal medullary cavity
* lesions often cross physis into metaphysis
* cortical expansion present
* soft tissue expansion rare
33
What is the DDX of the radiograph?
* Giant cell tumour
* chondroblastoma
* clear cell chondrosarcoma
* Osteomyelitis
34
What is seen on histology in chondroblastoma?
* Chondroblastoma arranged in **Cobblestones or dhicken wire-** see pic
* occasional multinucleated giant cells
* scattered multinucleated giant cells with focal areas of **chondroid matrix**
35
Describe the tx of chondroblastoma?
* operative
* **Extended intralesional curretage and bone grafting**
* in symptomatic pts
* **resection of rare benign pulmonary mets**
* if pulmonary mets exist
36
Describe chondromyxoid fibroma?
* A rare
* **Benign chondrogenic lesion**
* characterised by variable amounts of **chondroid, fibromatoid and myxoid elements**
* \> in **males**
* most common in 2nd/3rd decades of life
* location
* **long bones-** tibia, distal femur, pelvis ot hands
* Mutations of **chromosome 6 position q13**
* may reocur in 20-30% cases
37
What are the symptoms of chondromyxoid fibroma?
* **Long standing pain-** months- years
* Pain and swelling
38
What is seen on xrays with chondromyxoid fibroma?
* **Lytic, eccentric metaphyseal lesion**
* scalloped and sclerotic rim
* calcifications RARE
39
What is seen on mri with chondromyxoid fibroma?
* T1 weighted low signal
* T2 weighted high signal
40
What is seen with histology with chondromyxoid fibroma?
* Lobules of fibromyxoid tissue
* hyperchromatic nuclei
* lobules contain spindle shaped cells/stellate shaped
* high power stellate cells seen
41
What is the tx of chondromyxoid fibroma?
* Operative
* **intralesional curretage & bone graft ( or PMMA)**
* mainstay of tx
42
what are the complications of chondromyxoid fibroma?
* Reocurrance 25% cases
43
What is Chondrosarcoma?
* A Malignant chondrogenic lesion that can occur in 2 forms
* **primary chondrosarcoma**
* low grade,high grade
* **clear cell chondrosarcoma**
* **mesenchymal chondrosarcoma**
* **Secondary chondrosarcoma**
* arises from benign cartilage lesions
* **osteochondromas**
* **Mutliple hereditary exostosis**
* **Enchondromas** (1% transformation)
* **Ollier's disease** (20-45% transformation)
* **Maffucci** ( 100% transformation)
44
Describe the epidemiology of chondrosarcomas?
* Age
* older pts 40-75 yrs
* slight male predominance
* locations= **pelvis, prox femur, scapula**
* 85% of chondrosarcomas are grade 1/2
* **axial and proximal extremity lesions** have a more aggressive course
* survical
* grade 1 = 90%
* Grade 3= 30-50%
* de differentiated 10%
45
Describe clear cell chondrosarcomas?
* malignant immature cartilagenous toumour
* accounts for
* common 30-040 yrs
* insidious onset of pain
* **epiphyseal** in location ( ddx from GCT ( giant cells) /chondroblastoma ( young pts)
* locally destructive with potential to metastatsize
46
describe mesenchymal chondrosarcomas?
* chondrosarcomas variant which present with a biphasic pattern of neoplastic cartilage with associated neoplastic small round blie cell component
* younger pts
* tx includes neoadjuvant chemo then wide surgical resection
47
What does a pt with chondrosarcomas present with?
* **Pain** - most common
* **slow growing mass**/ bladder or bowel obstruction ( mass effect in pelvis)
* **50% of de-differentiated** chondrosarcomas pc **pathological fracture**
48
What is seen on xrays in a pt with chondrosarcomas?
* **Lytic or blastic reactive thicknening of cortex**
* low grade
* **similar appearance to enchondroma** w additional cortical thickneing/expansion
* high grade
* **cortical destruction & a soft tissue mass**
* intra-lesional **'popcorn mineralisation'**
* MRI- useful ti determine cortical destruction
* bone scan- v hot
49
Describe the histology of chondrosarcomas?
* **No needle biopsy as difficulties in diagnosis**
* low grade
* few mitotic figures with bland histologic appearance
* enlarged chondrocytes w plump nucleated lacunae - see pic
* high grade
* hypercellular stroma w blue balls of cartilage lesion which permeate the bone traecular
* De differentitated- high level of spindle cells
50
What is the tx of chondrosarcomas?
* Operative
* **Intra-lesional curettage**
* grade 1 lesions
* **Wide local excision**
* grade 2/3 lesions
* no sig role for radiotherapy/chemo as cartilage lesion is slow growing in typically intramedullary chondrosarcomas
* **Wide local excision w multi-agent chemo**
* _mesenchymal chondrosarcomas_
* the role of chemo in de-differentiated very controversial
