Bone Tumors
Periosteal Chondroma
James C. Wittig, MD
Sarcoma Surgeon
Orthopedic Oncologist
GENERAL INFORMATION
Benign neoplasm
Composed of mature hyaline cartilage
Arises from surface of bone from inner layer of periosteum
Erodes the outer table of the cortex
Does not grossly extend into medullary cavity
Also known as juxtacortical chondroma
More cellular than an enchondroma
CLINICAL PRESENTATION
Signs/Symptoms:
Incidental radiographic findings
Possible symptomatic mass
Mildly painful
Long duration of symptoms
Mechanical symptoms
Prevalence:
Very uncommon
Accounts for ~0.66% of bone tumors
3 times as common as juxtacortical chondrosarcoma
2 to 1 male predilection
Age:
All ages; usually <30 years
Most commonly in second or third decades of life
Sites:
Almost all in appendicular skeleton
Proximal humerus-Most common
Femur, tibia, phalanges are common sites
Pelvis, ribs, vertebrae less common
Occasionally multiple lesions occur
Difficult to differentiate from periosteal chondrosarcoma (periosteal chondrosarcomas are usually
greater than 6cm and periosteal chondromas are usually less than 6 cm)
RADIOGRAPHIC PRESENTATION
|
2/3 of periosteal chondromas involve metaphysis
Remainder arise on diaphysis
Long bone lesions
Size: 2-3 cm in size, up to 6 cm
Over 6cm is worrisome for periosteal chondrosarcoma
Short tubular bones
Size: Few mm to 3 cm in size,
usually between 1 and 2 cm
Eccentric, longitudinally oriented periosteal mass
Smooth, concave, often sclerotic contour
Subtle underlying cortical erosion
Outer Shell of Reactive Periosteum (Egg Shell Rim of Calcification around external surface)
Calcifications in a "Ring and Arc" manner and/or stippled calcifications
2/3 have distinct, well-defined peripheral borders
High intensity T2W MRI |
 | |
CT Scan: Periosteal Chondroma
X-ray: Distal Femur Periosteal Chondroma
GROSS PATHOLOGY
Well circumscribed
Appears to be embedded in underlying cortical bone
Typically covered by a thin shell of reactive, often ossified periosteum
Medullary cavity not grossly invaded
Cross-section
Blue-gray to white
Translucent hyaline cartilage
Often formed as lobules
Calcification occasionally noticeable
Yellow-white, gritty foci
MICROSCOPIC PATHOLOGY
Lobulated, obviously hyaline cartilage tumor
Cartilaginous lobules separated by fibrous connective tissue or well-formed lamellar bone
Calcium deposition occasionally present
Necrosis absent
Innermost margin of lesion usually demarcated by rim of lamellar bone
Considerable interlesional variation in cellularity and pleomorphism
Many consist of normocellular benign hyaline cartilage
Binucleated chondrocytes are invariably present
May be more cellular than an enchondroma with myxoid change of matrix
About 2/3 of tumors display
Nuclear enlargement
Hypercellularity with hyperchromasia
Or myxoid change of the matrix
Microscopic Pathology: Periosteal Chondroma
BIOLOGICAL BEHAVIOR
No metastasis
No malignant change
Exceedingly rare recurrence
Non aggressive
TREATMENT & PROGNOSIS
Marginal excision without removal of surrounding tissue
Occasional rare recurrence
En bloc excision
Invariable curative
|
