Chondroblastoma

Chondroblastoma

– benign tumors occurring in 2nd decade
– commonly found in proximal humerus, distal femur or proximal tibia (epiphysis of long bones but may be in an apophysis)

Signs & Symptoms:
– pain localized to region of tumor
– tenderness, pain on motion of the affected joint

Xrays:
– radiolucent lesion with well-defined sclerotic border with variable calcification in lesion
– may cross open physis & expand surrounding bone

Histology:
– round to polyhedral cells with well-defined cell borders containing indented nuclei
– matrix calcification may be present
– multinucleated giant cells – scattered & sometimes in large numbers
– cystic spaces resembling aneurismal bone cysts may be seen

Treatment:
– crettage & bone grafting à 90% cure rate
– rarely are locally aggressive or can metastasize