Giant cell tumor

Background

Distribution of giant-cell tumors of bone

• Benign tumor that is locally aggressive causing osteolytic destruction
• Although classified as benign lesions, metastasis does occur in a small percentage of patients, typically to lungs
  • These are known as benign pulmonary implants as they do not carry the same poor prognostic implication as lung metastasis from other malignancies
• 3% to 5% of all primary bone tumors
  • Around 20% in the Chinese population
• Increased incidence in patients who have been diagnosed with Paget disease of the bone

Clinical Features

• Pain and edema over a joint near a long bone (usually around the knee)
  • Classically in a young female adult
• Can present as a pathological fracture
• Nearly all present with just a single tumor site

Differential Diagnosis

Bone tumors and their mimics

Malignant

• Multiple myeloma
• Chondrosarcoma
• Paget disease
• Osteosarcoma
• Adamantinoma
• Chordoma
• Primary bone lymphoma
• Fibrosarcoma
• Myosarcoma

Benign

• Giant cell tumor
• Chrondroblastoma
• Enchondroma
• Langerhans cell histiocytosis of bone
• Osteoblastoma
• Osteochondroma
• Osteoid osteoma

Other

• Septic joint
• Fracture
• Abscess

Evaluation

X-ray of a giant-cell bone tumor in the head of the fourth metacarpal of the left hand

• Plain radiograph showing a large lytic mass with soap bubble appearance
• Obtain chest plain film to look for pulmonary metastasis
• CT and MRI for more accurate assessment of tumor
  • Possibly can be done as outpatient
• Biopsy for definitive diagnosis

Management

• Surgery is the treatment of choice
• RANKL inhibitors (Denosumab) for unresectable metastatic disease
• Can recur locally after curettage

Disposition

• Home with outpatient follow up
• Admission if necessary for pain control or significant disease burden