Benign Cartilage Forming Tumors Flashcards
What is the most common benign skeletal tumor?
osteochondroma
An osteochondroma is also called ____
exostosis
What age group is primarily affected by osteochondroma?
skeletally immature individuals
(<20), but keep it for the rest of life
What are the 2 types of osteochondroma?
- pedunculated
- sessile
Most cases of osteochondroma are ____
solitary
Less than 6 osteochondroma lesions is termed ____
solitary osteochondroma
What is the name for the multiple form of osteochondroma?
Hereditary Multiple Exostosis (HME)
More than 6 osteochondroma lesions is termed ____
Hereditary Multiple Exostosis (HME)
Hereditary Multiple Exostosis is also called ____
osteochondromatosis
What is a major difference between the solitary and multiple forms of osteochondroma in terms of possible outcomes?
- solitary: <1% chance of malignant transformation
- multiple: up to 25% undergo malignant transformation
If an osteochondroma undergoes malignant degeneration, what will it transform into?
- chondrosarcoma (most likely)
- osteosarcoma
What is the etiology of osteochondromatosis?
autosomal dominant hereditary disease
(EXT1 & EXT2 genes)
What is the etiology of solitary osteochondroma?
spontaneous development, no genetic component
Describe the appearance of a pedunculated osteochondroma
- bony stalk capped by cartilage
- should not be thicker than 10mm
Describe the appearance of a sessile osteochondroma
- don’t often have cartilaginous cap
- cartilage is intermingled
- “hill” on bone
At what point is a pedunculated osteochondroma considered to undergo malignant transformation?
when >2cm thickness
(use MRI to evaluate)
What is the preferential location of osteochondromas?
- knee is common
- pelvis, scapula, ribs
- metaphysis near growth plate of endochondral bones only
Describe the histological layers of a pedunculated osteochondroma
- bone
- hyaline cartilage
- perichondrium
How would a patient with sessile osteochondroma present clinically?
- generally painless (non-tender), non-mobile, potentially palpable lumps
- tendinosis/bursitis
- neurovascular bundle impingement
- malignant transformation (rare)
How would a patient with pedunculated osteochondroma present clinically?
- generally painless (non-tender), non-mobile, potentially palpable lumps
- pathological fracture
- tendinosis/bursitis
- neurovascular bundle impingement
- malignant transformation (rare)
How would a patient with Hereditary Multiple Exostosis present clinically?
- begin forming both sessile & pedunculated osteochondromas ~3 years old
- bowing/shortening of affected bones
- limited ROM
- multiple bones w/ exostoses (6-100s)
- family Hx
(in addition to SSx of solitary osteochondroma)
What is the treatment for solitary osteochondromas?
surgical removal, generally once skeletally mature (will only stop growing once pt stops growing)
What is the treatment for Hereditary Multiple Exostosis?
- surgical removal if clinical problems
- correction of bone deformities (osteotomy)
- address biomechanical issues
Name the 2 types of benign cartilaginous tumors
- enchondroma
- juxtacortical chondroma
What are enchondromas comprised of?
hyaline cartilage
What are juxtacortical chondromas comprised of?
hyaline cartilage
What population is primarily affected by benign cartilaginous tumors?
<20 years
Benign cartilaginous tumors form in ____ bones
endochondral
What is the preferential location of enchondromas?
medullary cavity
What is the preferential location of juxtacortical chondromas?
surface (cortical) of bone
What is the etiology of benign cartilaginous tumors?
mutation in genes related to chondrocyte development
If an enchondroma undergoes malignant degeneration, what will it turn into?
chondrosarcoma
(<1% chance in solitary lesion)
Multiple enchondromas are referred to as ____
Ollier Disease
(has possible hereditary component)
What is the chance of malignant transformation in Ollier Disease?
25%
Multiple enchondromas plus soft tissue hemangiomas are referred to as ____
Mafucci Syndrome
(rare)
Ollier Disease plus soft tissue hemangiomas are referred to as ____
Mafucci Syndrome
(rare)
What is the chance of malignant transformation in Mafucci Syndrome?
50%
What are the multiple forms of enchondroma called?
- Ollier disease
- Mafucci syndrome
What is a hemangioma?
benign vascular tumor
What is the most common benign tumor of the hands and feet?
Enchondroma
How would a patient with an enchondroma present clinically?
- usually asymptomatic (incidental finding)
- Patho Fx (painful)
- No Fx + pain = possible malignancy
How would you differentiate between an enchondroma and a chondrosarcoma?
use MRI with contrast (inject with gadolinium) to highlight vascular structures
- enchondroma shows up normal
- chondrosarcoma shows high contrast (^angiogenesis)
What are the radiographic characteristics of an enchondroma?
- geographic lytic lesion w/ or w/out sclerotic border
- narrow/short ZoT
- 50% have matrix calcification
- intact & thinned cortex, endosteal scalloping
- deformities
What is endosteal scalloping?
curvilinear edges (scalloped) of inside surface of bone (endosteum)
How would a patient with Ollier Disease present clinically?
- severe skeletal deformity
- shortened bones
- patho Fx
What type of matrix calcification is seen in Ollier disease?
stippled calcification (hyaline cartilage)
What is the pattern of destruction in Ollier disease?
geographic lytic
Small, round lumps of calcium that form in a person’s veins, which may show up as white spots radiographically are called ____
phleboliths
What are the radiographic characteristics of Mafucci syndrome?
- multiple geographic lytic lesions
- phleboliths outside of pelvic basin
Multiple phleboliths outside of the pelvic basin indicates ____
hemangiomas
How would a patient with Mafucci syndrome present clinically?
- shortened bones
- dense, purple-coloured skin
- bone deformities
- patho Fx
What is the treatment for benign cartilaginous tumors?
- none, unless symptomatic
- surgical removal of disruptive juxtacortical chondromas
- curettage of problematic enchondromas
- treatment of patho Fx
- monitor & treat for malignant degeneration
What is the preferential location of chondroblastomas?
epiphyses (articular ends) & apophyses of endochondral bones
What age group is primarily affected by chondroblastomas?
5-25 years
How would a patient with a chondroblastoma present clinically?
joint pain that is difficult to recreate with ortho tests
(bone pain, not mechanical)
What are the radiographic characteristics of chondroblastomas?
geographic lytic lesion in epiphyseal region
(slow-growing, well-defined borders)
What is the treatment for a chondroblastoma
surgical removal (curettage) due to severe pain
A 35 year old patient with a history of a single sessile osteochondroma arising from the medial aspect of the distal femur presents with pain immediately adjacent to that site. Light touch is intact, muscle testing of the leg is 5/5, and pulses are strong. What is the most likely explanation for why there is pain?
A) neurovascular bundle impingement
B) fracture
C) malignant degeneration
D) tendinosis/bursitis
D
