Cartilaginous tumours

Tumor	Age	Location	Clinical presentation	Pathology	Radiology	Treatment	Prognosis	DD
Enchondroma	10 - 50 yrs	metaphyseal.> 50% - small bones of the hands and feet.15% femur ,12% humerus. originating within the medullary cavity Periosteal form originates in the periosteum and erodes into the cortex	60% pathological fracture, lump or as incidental finding.75% solitary.Olliers disease ->more cellular and 50% ->malignant transformation.Mafuccis disease -> multiple haemangiomata , 100% malignant change	Macro - bluish white well demarcated, well encapsulated and often lobulated gritty tissue. Micro - hypocellular; nests of mature cartilage cells, nuclei are small and uniform, no atypia + calcification. Periosteal form less common , more cellular. Predilection for proximal humerus near deltoid insertion.	X-Rays Scalloped erosions on endosteal surface. flecks of calcification - sometimes called 'ground glass'. Periosteal form (juxtacortical) -shallow crater lined by rim of mature reactive bone, lifts periosteum	Observe - x-ray 6 months & 1 year after presentation. Curettage and grafting if latent. If active -> recurrence but this may be better than morbidity of en block excision.Periosteal form -> en bloc excision (with a margin)	Good	x
Chondroblastoma	10-20yrs, M>F	epiphyseal but may expand into metaphysis.Usually affects proximal humerus, proximal tibia or femur	ache progressive	Arises from chondroblasts.Usually active benign lesion (Stage 2).Histology ->pinkish grey tissue, lobulated, may be haemorrhagic, richly cellular multinucleate giant cells with polyclonal or round chondroblasts	Open physis. Well defined area of rarefaction eccentrically placed in the epiphysis or across the growth plate.No reaction in surrounding bone 50% show central calcification. 50% show linear periosteal reaction.Bone scan increased uptake at margins	Curettage & bone grafting (15% recurrence). avoid joint penetration because chondroblastoma cells will grow in joint fluid..Use cryotherapy if extension intra capsular to avoid excision of joint	no chance of malignant change	GCT (adults) ABC (histology similar) clear cell chondrosarcoma epiphyseal osteomyelitis
ChondroMyxoid Fibroma	10 - 30 years	eccentric metaphyseal lesions 75% lower extremity and 50% tibia	chronic ache	variable amounts of chondroid, fibromatoid & myxoid elements.May develop from a remnant of the growth plate ?.histo- firm lobulated jelly like areas of mucoid with condensations of cells on the periphery.areas of chondroid and myxomatous tissue. Contains giant cells, macrophages and monocytes.usually no bone osteoid	Rounded or oval rare area.Usually eccentric.May cross the growth plate. Sharp outline and sclerotic rim.Scalloped margin and thin cortex	Extra capsular marginal excision ->almost no recurrence.If skeletally immature wait until maturity	Malignant change has been reported, thus where possible it should be excised	x
Osteochondroma	under 20 yrs	metaphyseal area of any endochondral bone /50% are distal femur, upper tibia or proximal humerus	lump or interference of tendon function. sessile or pedunculated. Active growth during skeletal growth ->become latent.Move towards diaphysis with growth and usually angle away from the growth plate.Trevor's Disease: Osteochondroma on epiphyseal side of the growth plate	Normal bone covered by a cap of normal cartilage which resembles growth plate but more disorganized. Binucleate chondrocytes in lacunae.Covered with a thin layer of periosteum.Diaphysial Aclasis- Autosomal dominant. Disordered endochondral growth. Multiple osteochondromas and disordered metaphyseal growth. Short stature and bowing of limb. Malignancy Risk = ~ 20% overall or 0.2% per lesion	hallmark is blending of tumour into underlying metaphysis. well defined metaphyseal excrescence of bone with a mottled density Cartilaginous cap displays irregular areas of calcification . Bone scan -during growth period activity at the tip.increased activity after maturity suggests malignant change	Nil required unless symptomatic (persistent irritation (from bursitis or tendon) or neurovascular compromise. Extra capsular marginal excision Including the cartilaginous cap & overlying perichondrium.Deep bony base has minimal activity & may be removed piecemeal.cartilaginous cap should not be traumatised during removal.Recurrence = <>	malignancy ~ 0.2% in a solitary lesion. low grade.Evidence- Cartilaginous cap thicker than 1 cm in an adult (in child may be 2-3 cm thick) Cartilage cap > 8cm diameter. Fluffy outline. Bone scan - Marked increase in uptake in an adult. CT/MRI - soft tissue mass or displacement of a major neurovascular bundle	Myositis ossificans, Parosteal osteosarcoma