Chondroblastoma: A Clinico-pathological Analysis

Objective: To determine the clinico-pathological and histological features of Chondroblastoma (CB). Study Design: Case series. Place and Duration of Study: The Aga Khan University Hospital, Karachi, from 2000 to 2013. Methodology: The histological slides of all reported cases of CB were retrieved and reviewed for morphological features. Clinical features were noted from surgical pathology reports. Frequency of features was noted. Results: Sixty one cases of CB were identified. Pain was the most common presenting symptom. The age ranged from 10 to 38 years (mean 20 +/- 1.98 years; M: F 2.5:1) with 61% patients in the second decade of life. Forty six cases occurred in long tubular bones; distal femur being most common site. Metaphysis, clavicle, temporal bone and metacarpal were also involved. Histologically, all CBs were composed of round to polygonal cells and scattered osteoclast-type multinucleated giant cells and majority had hennosiderin pigment. Chicken-wire calcifications and coarse calcifications were seen in 85% and 26% of cases respectively. A spindle cell component was seen in 54% of cases. ABC-like areas were seen in 10 cases. Mitosis ranged from 1 to 6/10 HPFs. Recurrence was seen in 2 cases. Recurrent tumor showed similar morphology when compared with the initial tumor. Conclusion: CB is a benign tumor but has potential for recurrence. Males are more affected, second decade is more common and distal femur is most common site. Metaphysis, clavicle, temporal bone and metacarpal were the rare sites of CB. Histological features predictive of recurrence were not separately identified.