<prompt> Not true regarding Giant Cell TumorBenign bone tumorUsually solitarySpine involvement is commonAge group affected in usually between 20-40 years  <response>: Ans. c Spine involvement is common Ref. Bailey and Love Surgery 25thpg. 471; Maheshwari orthopaedics 2ndpg. 215GIANT CELL TUMOR OSTEOCLASTOMA It is an aggressive but benign tumor of bone. Occurs most commonly at epiphyseal end of long bones most common around the knee: distal femur and proximal tibia: 50-65. Peak incidence 20-40 years old. Eccentric, Epiphyseal subarticulaar, Expansile Benign Bone tumor. Locally aggressive benign tumor often around the distal femur, proximal tibial region. Characteristic soap bubble appearance on X-ray. Spindle-shaped cells with multinucleated giant cells. Tumor invasion of the soft tissue occurs in 25 of cases. 3Es of GCT Osteoclastoma:- Epiphyseal- Expansile- Eccentric Bone tumors of epiphyseal origin Osteoclastoma GCT and Chondroblastoma Codmans tumor. 