Peak age: congenital, diagnosed by 10 yo; Male/Female 1:1; Favored location: Any bone
Malignant transformation in 1/3 of cases
Same as solitary lesion.
More cellular, more cytologic atypia and more myxoid (mucus-like) than solitary lesion
Ollier’s and Maffucci may be hard to distinguish from chondrosarcoma.
– group of tumors who all have the common feature of producing neoplastic cartilage
In contrast to enchondroma - rarely involves distal extremities.
Subclassified by site: Intramedullary and Juxtacortical as well as histological variants: Conventional (hyaline and/or myxoid), clear cell, dedifferentiated, and mesenchymal
Peak age: adulthood (4th – 6th decade); M/F = 1.5:1; Favored local: Central skeleton and proximal extremities.
pain that wakes you at night or mass lesion.
Conventional – gray-white large bulky nodules, translucent and glistening
Myxoid – viscous and gelatinous; spotty calcification; central necrosis causing cystic spaces; tumor grows with broad pushing fronts into soft tissue and invades marrow space
Predilection for central skeleton and metaphysis and diaphysis of the affected bone.
Cortical erosion or destruction is possible
Soft tissue extension is commonly seen in large lesions
The more radiolucent the tumor, the more likely it is high grade.
Destructive invasion seen at cortex
Divided into 3 Grades based on extent of Cellularity, pleomorphism and mitosis
Low Grade 1: mild hyper cellularity, chondrocytes have plump, vesicular nuclei with small nucleoli. Binucleated cells and mitotic figures are hard to find. Partial mineralization and endochondral ossification may occur.
High Grade 3: marked hypercellularity, extreme pleomorphism with bizarre tumor giant cells and mitosis.
Often you see cancellous bone encompassed by chondrocytes.
Ceases to grow in adulthood
Well defined border
Poorly defined margin
Regular ring like mineralization
Irregular mineralization, poorly defined area
No cortical destruction, thickening
Cortical thickening or erosion
Chondrosarcoma can arise from < 1% of Osteochondromas
. (Risk is higher in the hereditary syndrome)
in between the two: 3rd and 4th decade. M/F: 2:1 Favored local: = ilium, humerus, femur
: a mass lesion that recently has increased in size; pain likely.
: thick indistinct cartilage cap with radiolucent regions; destruction of underlying osteochondroma
: same as chondrosarcoma.
– a primary malignant small cell tumor of bone
6-10% of primary bone tumors (600/yr)
Use to be fatal in 1st year, now 60% survival at 5yrs (at least 50% long-term cure).
Resembles: lymphoma, rhabdomyosarcoma, neuroblastoma and oat cell carcinoma.
Ewing sarcoma tumor cells exhibit neural phenotype as do primitive neuroectodermal tumors (PNET)
both express c-myc oncogene (MIC2)
85% have t(11,22) (q24,q12) translocation. (syllabus has this screwed up; Karim said we need to know this)
identification of this translocation is diagnostic of this disease
Tumors that demonstrate neural differentiation by light or electron microscopy, immunohistochemisrty = PNET
Tumors that are undifferentiated by these analysis are diagnosed as Ewings sarcoma.