Giant-cell tumor of bone
Giant-cell tumor of bone | |
---|---|
Other names | Osteoclastoma |
Micrograph of a giant-cell tumor of bone showing the characteristic giant cells, H&E stain | |
Specialty | Oncology, orthopedic surgery |
Giant-cell tumor of the bone (GCTOB), is a relatively uncommon
Signs and symptoms
Patients usually present with pain and limited range of motion caused by tumor's proximity to the joint space. Swelling may occur, as well, if the tumor has been growing for a long time. Some patients may be asymptomatic until they develop a pathologic fracture at the site of the tumor. They usually originate from the epiphysis of long bones, but in rare cases, they may arise from anterior arc of the ribs.[7] The symptoms may include muscular aches and pains in arms or legs and abdominal pain. Patients may also experience nerve pain which feels like an electric shock due to weight bearing.[citation needed]
Diagnosis
The diagnosis of giant-cell tumors is based on biopsy findings. The key histomorphologic feature is, as the name of the entity suggests, (multinucleated) giant cells with up to a hundred nuclei that have prominent nucleoli. Surrounding mononuclear and small multinucleated cells have nuclei similar to those in the giant cells; this distinguishes the lesion from other osteogenic lesions which commonly have (benign) osteoclast-type giant cells. Soap-bubble appearance is a characteristic feature.[citation needed]
Imaging
On X-ray, giant-cell tumors (GCTs) are lytic/lucent lesions that have an epiphyseal location and grow to the articular surface of the involved bone.[8] Radiologically the tumors may show characteristic 'soap bubble' appearance.[9] They are distinguishable from other bony tumors in that GCTs usually have a nonsclerotic and sharply defined border. About 5% of giant-cell tumors metastasize, usually to a lung, which may be benign metastasis,[10]
Plain radiograph is still the main method of diagnosing giant cell tumour. But MRI and CT scans are useful for staging and surgical planning. CT is more superior than plain radiograph in delineating the tumour outline, its extension into structures outside the bone, determining the involvement of bony cortex and tumour recurrence. CT scans show features such as thin and expanded bony cortex, with or without bony matrix calcifications, and fluid levels due to aneurysmal bone cyst or bleeding within tumour. However, axial views of the subarticular bone (bony area adjacent to the articular cartilage) is not accurate due to voxel signal averaging. MRI is superior than CT on delineating the tumour because of its better contrast resolution and imaging in multiple planes. MRI is also useful in determining the extension outside the bone and evaluating the involvement articular surface, skip lesions within bony matrix, and medullary cavity. However, bony cortex destruction is better demonstrated on CT scan.[11]
On MRI, the mass generates intermediate to reduced signal intensity on T1-weighted images, and increased signal intensity on fluid sensitive MRI images such as
Differential diagnosis
A number of tumors have giant cells, but are not true benign giant-cell tumors. These include,
Treatment
General treatment regimens have not changed much in the past 30 years, in part due to the lack of randomized clinical trials.[4] Surgery is the treatment of choice if the tumor is determined to be resectable. Curettage is a commonly used technique.[12] The situation is complicated in a patient with a pathological fracture. It may be best to immobilize the affected limb and wait for the fracture to heal before performing surgery.
Patients with tumors that are not amenable to surgery are treated with radiation therapy.
Epidemiology
Giant-cell tumor of the bone accounts for 4-5% of primary bone tumors and about 20% of benign bone tumors.[15] However, significantly higher incidence rates are observed in Asia, where it constitutes about 20% of all primary bone tumors in China.[16] It is slightly more common in females, has a predilection for the epiphyseal/metaphyseal region of long bones,[2][17] and generally occurs in the third to fourth decade.[14] Although classified as a benign tumor, GCTOB has been observed to metastasize to the lungs in up to 5% of cases, and in rare instances (1-3%) can transform to the malignant sarcoma phenotype with equal disease outcome.[2][4][17]
See also
References
- PMID 16162299.
- ^ PMID 17013643.
- PMID 10702390.)
{{cite journal}}
: CS1 maint: multiple names: authors list (link - ^ S2CID 41807503.
- PMID 17013643.
- PMID 14608531.)
{{cite journal}}
: CS1 maint: multiple names: authors list (link - ^ Dehghan A, Moaddab AH, Eskandarlou M, Moeeni A. Anterior chest wall giant cell tumor. Gen Thorac Cardiovasc Surg. 2010 Jan;58(1):39-41.
- PMID 11553835.
- ISBN 978-0-7817-3946-7. GGKEY:29STUY0DQ70. Retrieved 21 June 2010.
- ^ "Giant-cell tumor of bone - Wheeless' Textbook of Orthopaedics". 22 July 2020.
- ^ PMID 23322837.
- S2CID 2971150.
- S2CID 31907929.
- ^ S2CID 31907929.)
{{cite journal}}
: CS1 maint: multiple names: authors list (link - PMID 12579271.
- S2CID 41807503.
- ^ PMID 18311114.)
{{cite journal}}
: CS1 maint: multiple names: authors list (link