April 11, 2024

Giant Cell Tumor is the commonest benign tumor that is encountered by an orthopedic surgeon which consists of 5% of all skeletal tumors and 20% of all skeletal neoplasms.

The peak incidence of this tumor occurs in skeletally mature individuals in 3rd decades of their lives.

Female: Male= 1.5:1

GCT is seen in epiphysis after epiphyseal closure.

Clinical Features of GCT

Pain presents with variable severity

Mass is present

5 – 10 % of individuals present with pathological fractures

A common location is a Knee > Distal radius

Radiological Features of GCT

Lytic lesion centered in epiphysis involving metaphysis involving at least or a part of subchondral bone.

Bulging of tumor beyond the cortex is seen

The tumor has mostly well-defined margins, sometimes ill-defined, and seldom a thin shell of reactive bone.

No mineralized tumor matrix is found

Characterized lobulated: Soap Bubble appearances are seen

Sometimes free fluid level is seen which is secondary to ABC.

MRI shows Doughnut Sign

GCT

Campanacci Grading based on Radiological Appearances

GradeFeatures
Grade IWell-defined border of the thin rim of mature bone and the cortex was intact or slightly thinned out
Grade IIRelatively well marginated but no radioopaque rim; the combined cortex and rim of reactive bone was rather thin and moderately expanded but still present.
Grade IIIFuzzy borders, suggesting rapid and possible [ermeative growth; tumor bulged into soft tissue but soft tissue mass did not follow the contour of bone and was not limited by the apparent shell of reactive bone.

Pathology

Epiphysis in location, eccentrically placed

Surrounded by a thin rim of reactive bone

Reddish brown to yellow

Microscopic Examination:

  • Round to polygonal mononuclear cells and multinucleated osteoclast-like giant cells (> 50 nuclei)
  • Uniformly scattered
  • Storiform arrangement of fibroblast

Treatment of Giant Cell Tumor

Function preserving surgery:- Intralesional curettage with appropriate reconstruction

Expandable bones like the lower end of the ulna/ upper end of the fibula excision of the lesion are advocated.

Treatment plan of GCT

Role of Chemotherapy and Radiotherapy

Radiation therapy is done in unresectable lesions, especially in the spine

Role of embolization and bisphosphonates

In Unresectable GCT (Near spinal cord, sacral, and pelvis tumors)

Recurrence rate: High as 30-50% mostly in the first 2 years.

Pulmonary metastasis is seen in 1 % to 6 %.

Local recurrence with repeated surgical intervention seems to be associated with lung metastasis.

Malignant transformation is unusual but reported. Post-reduction sarcoma can develop.

Denosumab:

Denosumab is used in inoperable tumors

If the joint cannot be saved go for the resection, denosumab will help in thickening the wall for graft.

Still, there is a high chance of recurrence.

See also: Osteoblastoma

See also: Osteoid Osteoma

See also: CHONDROBLASTOMA

Previous Post