Table 1.

Demographic and clinical characteristics (N = 73).

Characteristic	Number of patients (%)
Male (n, %)	45 (61.6%)
Age at diagnosis (years)
Mean	14
Range	5–17
Histological subtype
Osteoblastic	52 (71.3%)
Chondroblastic	12 (16.4%)
Telangiectatic	5 (6.8%)
Fibroblastic	3 (4.1%)
Other	1 (1.4%)
Location of tumor
Distal femur	33 (45.2%)
Proximal tibia	15 (20.5%)
Proximal femur	10 (13.7%)
Humerus	9 (12.3%)
Fibula	6 (8.3%)
Distant metastases at onset
Yes	27 (37%)
No	46 (63%)
Histological response (n = 40)
≥90%	21 (52.5%)
<90%	19 (47.5%)
Elevated serum AP	58 (79.5%)
Elevated serum LDH	57 (78.1%)
Type of surgery
Conservative	31 (42.5%)
Amputation	42 (57.5%)
Tumor size (n = 32)
≤12 cm	25 (78.1%)
>12 cm	7 (21.9%)