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
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 >2mm 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