Cytological diagnosis of chondroblastoma: diagnostic challenge for the cytopathologist.

Chondroblastoma is an uncommon osseous neoplasm that accounts for less than 1% of all bone tumours. It characteristically arises in the epiphysis or epimetaphyseal region of long bones and has been reported to affect people of all ages with slight male predilection. WHO has defined chondroblastoma as 'a benign, cartilage-producing neoplasm usually arising in the epiphyses of skeletally immature patients'. The authors document the cytological features on fine-needle aspiration cytology of a chondroblastoma which appeared as a lytic lesion in the upper end of the right fibula, an uncommon site, in an 18-year-old male patient. X-ray feature combined with fine-needle aspiration cytology favoured the diagnosis of chondroblastoma, which was further confirmed by histopathological examination.