'Salvage Treatment' of Aggressive Giant Cell Tumor of Bones with Denosumab

Giant cell tumor of the bone (GCTB) presents as a lytic lesion of epiphyseometaphyseal regions of the long bones usually during the second to the fourth decade with female predilection. Histologically, they are formed of neoplastic mononuclear cells with a higher receptor activator of nuclear factor kappa-B ligand (RANKL) expression responsible for the aggressive osteolytic nature of the tumour. RANKL helps in the formation and functioning of osteoclasts. A newer molecule, Denosumab, is a monoclonal antibody directed against RANKL and thus prevents the formation and function of osteoclasts. Management of refractory, multicentric, recurrent, or metastatic GCTB remains challenging as achieving a tumor-free margin surgically is not always possible. Denosumab may play a crucial role, especially in the management of such difficult lesions. We present three cases of locally aggressive GCTB (involving proximal humerus, sacrum, and proximal femur) that were treated and responded very well to Denosumab therapy.

Reconstruction of the Midfoot Using a Free Vascularized Fibular Graft After En Bloc Excision for Giant Cell Tumor of the Tarsal Bones: A Case Report

We report the case of a 32-year-old Japanese female with a giant cell tumor of bone involving multiple midfoot bones. Giant cell tumors of bone account for approximately 5% of all primary bone tumors and most often arise at the ends of long bones. The small bones, such as those of the hands and feet, are rare sites for giant cell tumors. Giant cell tumors of the small bones tend to exhibit more aggressive clinical behavior than those of the long bones. The present patient underwent en bloc tumor excision involving multiple tarsals and metatarsals. We reconstructed the longitudinal arch of the foot with a free vascularized fibular graft. At the 2-year follow-up visit, bony union had been achieved, with no tumor recurrence.

Objective tumor response to denosumab in patients with giant cell tumor of bone: a multicenter phase II trial

A RANK ligand-specific inhibitor, denosumab, was predicted to reduce osteolysis and control disease progression in patients with giant cell tumor of bone (GCTB). We report, for the first time, the results of the response of GCTB to denosumab obtained from a prospective independent imaging assessment. The findings demonstrate that denosumab has robust clinical efficacy in the treatment of GCTB.

Background

Giant cell tumor of bone (GCTB) is a rare primary bone tumor, characterized by osteoclast-like giant cells that express receptor activator of nuclear factor-kappa B (RANK), and stromal cells that express RANK ligand (RANKL), a key mediator of osteoclast activation. A RANKL-specific inhibitor, denosumab, was predicted to reduce osteolysis and control disease progression in patients with GCTB.

Patients and methods

Seventeen patients with GCTB were enrolled. Patients were treated with denosumab at 120 mg every 4 weeks, with a loading dose of 120 mg on days 8 and 15. To evaluate efficacy, objective tumor response was evaluated prospectively by an independent imaging facility on the basis of prespecified criteria.

Results

The proportion of patients with an objective tumor response was 88% based on best response using any tumor response criteria. The proportion of patients with an objective tumor response using individual response criteria was 35% based on the modified Response Evaluation Criteria in Solid Tumors (RECIST) criteria, 82% based on the modified European Organization for Research and Treatment of Cancer (EORTC) criteria, and 71% based on inverse Choi criteria. The median time of study treatment was 13.1 months.

Conclusion

The findings demonstrate that denosumab has robust clinical efficacy in the treatment of GCTB.

Critical hypercalcemia following discontinuation of denosumab therapy for metastatic giant cell tumor of bone

We report a 14 year-old female with Giant Cell Tumor of Bone, successfully treated with denosumab, who developed critical hypercalcemia after completion of therapy. Five months after her last denosumab treatment, serum calcium rose to 16.5 mg/dL (normal 8.7-10.8 mg/dL), nearly double her prior level of 8.4 mg/dL while receiving denosumab. She required emergent intervention to treat her hypercalcemia, which was attributed to rebound osteoclast activity and osteopetrotic bone. Denosumab is widely used in adults and increasingly in pediatric oncology populations and our experience demonstrates the need for close monitoring for electrolyte derangements following discontinuation.

Effects of thermoablation with or without caffeine on giant cell tumour of bone

PURPOSE

To evaluate the effect of caffeine on the apoptosis rate of giant cell tumour of bone cells during thermoablation.

METHODS

Giant cell tumour of bone tissue (2 cm3) was collected from 10 patients. Cells were incubated at 37ºC, 40ºC, 45ºC, 50ºC, 52.5ºC, and 55ºC for 20 minutes (3 tubes for each temperature). Caffeine was added to the tubes in amounts of 0 μg/ml (control), 50 μg/ml, and 100 μg/ml. The apoptotic effect of thermoablation with or without caffeine was evaluated.

RESULTS

In all test conditions, the apoptotic rate of tumour cells increased when the temperature increased. Compared with controls (no caffeine), adding 50 or 100 μg/ml of caffeine did not increase the apoptotic rate significantly at 40ºC to 52.5ºC. Caffeine had no enhancing effect at any temperature. Conversely, at 55ºC, the apoptotic rate was lower when 100 μg/ml of caffeine was added than when no or 50 μg/ml of caffeine added (p=0.045).

CONCLUSION

Thermoablation at 40ºC to 52.5ºC for 20 minutes increased the apoptosis rate of giant cell tumour of bone cells. Caffeine had no enhancing effect at any temperature. Conversely, at 55ºC, caffeine had cytoprotective effects on the tumour cells against thermoablation.

Giant cell tumour of the distal humerus: a case report

Giant cell tumour of the distal humerus is rare. We report one such case in a 30-year-old man who underwent wide resection of the tumour followed by total elbow arthroplasty using a cemented 'sloppy-hinged' total elbow prosthesis. At the 18-month follow-up, the patient had pain-free range of motion of 15º to 120º and no evidence of recurrence.

Reconstruction of the distal radius with non-vascularised fibular graft after resection of giant cell tumour of bone

PURPOSE

To evaluate outcomes of wide resection and reconstruction of the distal radius with non-vascularised autogenous fibular grafts for giant cell tumour (GCT) of bone.

METHODS

Medical records of 7 men and 5 women aged 22 to 47 (mean, 31) years who underwent wide resection of the distal radius and reconstruction with non-vascularised autogenous fibular grafts for GCT of bone were reviewed. The mean length of the resected radius was 9 (range, 7-11) cm. The ipsilateral proximal fibula with a small portion of attached ligament was harvested. The articular surface of the graft was fixed to the scapholunate articular surface by Kirschner wires, and the ligament of the fibular head was sutured to the carpal ligaments. The graft was fixed to the proximal radius with a small dynamic compression plate. Iliac cancellous bone graft was added. Pain, instability, and functional status were assessed. Wrist joint movements were measured using a goniometer. The grip strength was measured. The operated and contralateral sides were compared.

RESULTS

The mean follow-up was 24 (range, 20-27) months. All patients achieved radiological union after a mean of 16 (range, 14-20) weeks. The mean active range of movement in the operated wrists was 32º dorsiflexion, 38º palmar flexion, 15º radial deviations, 12º ulnar deviations, 50º supination, and 60º pronation. Compared with the contralateral wrists, the operated wrists regained 60% of the function, with satisfactory grip strength, and normal finger and thumb movements and hand sensation. No patient had recurrence after 2 years. Two patients had minor dorsal subluxation, which was resolved with a wrist brace. Three patients had superficial infection, which was resolved with intravenous antibiotics and dressings. Two patients had peroneal nerve palsy, which recovered completely in 12 weeks.

CONCLUSION

Non-vascularised fibular grafts for reconstruction of the distal radius after resection of a GCT of bone achieved good cosmetic and functional outcomes.

Curettage and reconstruction by the sandwich technique for giant cell tumours around the knee

PURPOSE

To evaluate outcomes of 36 patients who underwent curettage, use of phenol, and reconstruction using the sandwich technique for giant cell tumour (GCT) of bone around the knee.

METHODS

22 women and 14 men aged 19 to 46 (mean, 29.6) years underwent intralesional curettage, use of phenol, and reconstruction using the sandwich technique for GCT of the proximal tibia (n=23) or distal femur (n=13). Two of the cases were recurrences. Two, 18, and 16 tumours were classified as grade I, grade II, and grade III, respectively. Five of the grade III tumours were associated with an extra-articular pathological fracture. Patients underwent intralesional curettage, use of phenol, and reconstruction with allograft, gel foam, and cement (the sandwich technique). Pathological fractures were fixed with plates. Functional outcome was evaluated using the Musculoskeletal Tumor Society (MSTS) score.

RESULTS

The mean follow-up period was 5 (2.5-11) years. The mean MSTS score was 27.7 out of 30 (standard deviation, 3; range, 16-30). One patient with a grade III tumour in the proximal tibia had a recurrence detected elsewhere after 3 years. Her MSTS score at 2 years was 26. No patient had malignant transformation.

CONCLUSION

Intralesional curettage, use of phenol, and reconstruction with allograft, gel foam, and cement (the sandwich technique) for GCT of bone achieved good functional outcome and a low recurrence rate.

Giant Cell Tumors of the Foot and Ankle Bones: High Recurrence Rates After Surgical Treatment

Giant cell tumor (GCT) of the bone is a benign primary bone tumor most often treated with intralesional surgery. Most cases occur around the knee; however, rarely, GCT of bone can occur in the foot and ankle. Limited data exist about the outcomes after treatment of GCT in this location. We retrospectively reviewed an orthopedic oncology database from 1970 to 2010 for cases of GCT of the bone, specifically within the foot and ankle bones. After exclusionary criteria were applied, a total of 19 disease sites in 18 patients were included for analysis. Of the 19 disease sites, 10 recurred. Patients, on average, required 1.7 operations per disease site. Of the 18 patients, 10 required ≥2 operations, 3 required ≥3 operations, and 1 required 4 operations. A total of 4 amputations were performed, including 2 below the knee amputations. Of the 10 patients with recurrence, 2 also had evidence of metastatic disease. The recurrence rates of GCT in the foot and ankle bones appear to be greatest after intralesional curettage without the use of cement. Although the recurrence rates are high, intralesional operations with multiple adjuvant therapy can eventually result in cure.

Isocitrate dehydrogenase mutation is frequently observed in giant cell tumor of bone

Giant cell tumors of bone (GCTB) are benign and locally destructive tumors that include osteoclast-type multinuclear giant cells. No available treatment is definitively effective in curing GCTB, especially in surgically unresectable cases. Isocitrate dehydrogenase (IDH) mutations have been reported not only in gliomas and acute myeloid leukemias, but also in cartilaginous tumors and osteosarcomas. However, IDH mutations in GCTB have not been investigated. The IDH mutations are remarkably specific to arginine 132 (R132) in IDH1 and arginine 172 (R172) or arginine 140 (R140) in IDH2; IDH1/2 mutations are known to convert α-ketoglutarate to oncometabolite R(-)-2-hydroxyglutarate. We recently reported that the most frequent IDH mutation in osteosarcomas is IDH2-R172S, which was detected by MsMab-1, a multispecific anti-IDH1/2 mAb. Herein, we newly report the IDH mutations in GCTB, which were stained by MsMab-1 in immunohistochemistry. DNA direct sequencing and subcloning identified IDH mutations of GCTB as IDH2-R172S (16 of 20; 80%). This is the first report to describe IDH mutations in GCTB, and MsMab-1 can be anticipated for use in immunohistochemical determination of IDH1/2 mutation-bearing GCTB.

The hypermetabolic giant: 18F-FDG avid giant cell tumor identified on PET-CT

An 87 year-old white female presented with a two-year history of intermittent discomfort in her left foot. PET-CT identified intense18F-fluorodeoxyglucose (FDG) uptake corresponding to the lesion. Histology of a fine needle aspiration and open biopsy were consistent with a benign giant cell tumor (GCT) of the bone. GCT of bone is an uncommon primary tumor typically presenting as a benign solitary lesion that arises in the end of the long bones. While GCT can occur throughout the axial and appendicular skeleton, it is exceedingly uncommon in the bone of the foot. While 18F-FDG has been established in detecting several malignant bone tumors, benign disease processes may also be identified. The degree of 18F-FDG activity in a benign GCT may be of an intensity that can be mistakenly interpreted as a malignant lesion. Therefore, GCT of the bone can be included in the differential diagnosis of an intensely 18F-FDG-avid neoplasm located within the tarsal bones.

Beta-human chorionic gonadotropin expression in recurrent and metastatic giant cell tumors of bone: a potential mimicker of germ cell tumor

Giant cell tumors of bone (GCTs) are generally benign, locally aggressive neoplasms that rarely metastasize. The beta subunit of human chorionic gonadotropin (beta-hCG) is expressed in syncytiotrophoblasts and several nongynecologic neoplasms but has not been described in GCT. At our institution, we observed cases of elevated beta-hCG in patients with GCT leading to diagnostic difficulty and in one case, concern for metastatic choriocarcinoma. This study aims to determine the frequency of beta-hCG expression in GCT and any relationship to clinical aggressiveness. We evaluated tissue expression of beta-hCG by immunohistochemistry with 58% of cases staining for beta-hCG. Additionally, 2 of 11 patients with available serum and/or urine beta-hCG measurements demonstrated elevated beta-hCG due to tumor. It is important to be aware of beta-hCG expression by GCT and the potential for elevated urine and serum beta-hCG levels in patients with GCT so as to avoid misdiagnosis of pregnancy or gestational trophoblastic disease.

Risk factors for recurrence of giant cell tumours of bone

PURPOSE

To determine the risk factors for recurrence of giant cell tumours (GCTs) of bone.

METHODS

Medical records of 29 men and 29 women (mean age, 34 years) treated for primary (n=53) or recurrent (n=5) GCTs of bone and followed up for a mean of 40.2 months were reviewed. The tumours were located in the distal femur (n=18), proximal tibia (n=10), proximal femur (n=8), distal radius (n=7), proximal fibula (n=4), distal ulna (n=3), calcaneum (n=3), sacrum (n=2), vertebra (n=1), metatarsal (n=1), and distal humerus (n=1). 26 patients had pathological fractures, 12 had cortical break, and 20 had neither. The Campanacci grades of the tumours were I (n=1), II (n=18), and III (n=33); the grades of the remaining 6 tumours were unknown because radiographs were unavailable. The Enneking stages of the tumours were 1 (n=51), 2 (n=6), and 3 (n=1). Treatment included curettage and cementation (n=29), curettage, cementation, and adjuvant treatment with distilled water or liquid nitrogen for bones without fracture (n=18), wide resection for extensive soft tissue involvement (n=9), and amputation (n=2) for a recurrent GCT of the distal femur and a primary GCT of the calcaneus. Reconstruction included cementation (n=27), bone grafting (n=7), cementation/bone grafting with internal fixation (n=14), reconstruction with endoprosthesis (n=3), and none (n=7).

RESULTS

19 patients had recurrence after a mean of 23.1 months. The overall recurrence-free survival at years 1, 2, and 3 were 86%, 79%, and 72%, respectively. Recurrence did not correlate with patient age (p=0.20), primary or recurrent tumour at presentation (p=0.12), Campanacci grade (p=0.10), Enneking stage (p=0.54), or presence of pathological fracture (p=0.28). Compared to GCTs at other locations, GCTs in the proximal tibia were more likely to recur (27% vs. 60%, p=0.04).

CONCLUSION

GCTs of the proximal tibia are more likely to recur than those at other locations.

Time required for effective action of phenol against giant cell tumour cells

PURPOSE

To evaluate the time required for effective action of phenol against the giant cell tumour (GCT) cells.

METHODS

Fresh GCT cells were harvested from 9 patients with primary GCT of the distal femur (n=4), proximal tibia (n=4), and proximal humerus (n=1), with the Campanacci tumour grades 3 (n=6), 2 (n=2), and 1 (n=1). Specimens were immersed in 80 % phenol for one, 3, 6, and 10 minutes, and were assessed by a single pathologist for irreversible cell death and the depth of phenol penetration.

RESULTS

Phenol caused consistent GCT cell death in 6 of the 9 specimens after 3 minutes and in all 9 specimens after 6 minutes, compared to none in controls (p<0.0001). The mean depths of phenol penetration were 15 (range, 11-20) and 19 (range, 15-25) cell thickness after 6 and 10 minutes, respectively (p<0.0001).

CONCLUSION

GCT cells immersed in 80% phenol for 6 minutes resulted in consistent cell death.

p63 as a prognostic marker for giant cell tumor of bone

BACKGROUND AND PURPOSE

Giant cell tumor of bone (GCT) is sometimes difficult to distinguish from other giant-cell-rich tumors such as chondroblastoma (CHB) and aneurysmal bone cyst (ABC). The usefulness of p63 as a diagnostic marker for GCT is controversial. While there have been no reports about p63 as a prognostic marker for local recurrence, various p63-positive rates in GCT have been reported. The purpose of this study was to investigate retrospectively whether p63 is useful as a diagnostic marker and/or a prognostic marker for local recurrence of GCT.

METHODS

This study included 36 patients diagnosed with either GCT (n = 16), CHB (n = 9), ABC (n = 7), or non-ossifying fibroma (NOF) (n = 4). p63 immunostaining was performed for all specimens. The mean p63-positive rate was compared with the four diseases and between the recurrent and non-recurrent cases of GCT.

RESULTS

Although the mean p63-positive rate for GCT (36.3%) was statistically higher than that of all other diseases examined (CHB: 15.2%; ABC: 5.8%; NOF: 3.4%), p63 was not specific for GCT. The mean p63-positive rate for recurrent GCT cases (73.6%) was statistically higher than that for non-recurrent cases (29.1%).

CONCLUSION

In the diagnosis of GCT, p63 is a useful but not a conclusive marker. However, p63 did appear to indicate the biological aggressiveness of GCT. Therefore, p63 may help surgeons to estimate the risk of recurrence after surgery and help them to choose the best treatment for each GCT case.

Expression of osteoprotegerin and osteoprotegerin ligand in giant cell tumor of bone and its clinical significance

In this study, we used a substance P (SP) immunohistochemical method to analyze the expression localization of osteoprotegerin (OPG) and osteoprotegerin ligand (OPGL) in giant cell tumor (GCT) of the bone, and to detect the clinical significance of their expression. The data showed that the positive expression rate of OPG in the multinucleated giant cells (MGCs) and stromal cells (STCs) of GCT was 80.65 and 74.19%, respectively. The positive expression rate of OPG in MGCs was correlated with age and prognosis (P<0.05), but not in STCs. The strength of positive OPG expression in MGCs and STCs was negatively correlated with prognosis (rs=-0.397, P<0.05; rs=-0.390, P<0.05, respectively). The positive expression rate of OPGL in the MGCs and STCs was 41.94 and 67.74%, respectively. The positive expression rate of OPGL in the MGCs was correlated with age and prognosis (P<0.05); the strength of OPGL expression in MGCs was positively correlated with Campanicci's grade and recurrence. Additionally, the positive expression rate of OPGL in STCs was correlated with age and Jaffe's grade (P<0.05). The strength of OPGL expression in STCs was negatively correlated with Jaffe's grade (rs=-0.534, P<0.05). In conclusion, OPG and OPGL are expressed in MGCs and STCs in GCT of the bone. The invasion of tumor cells was positively correlated with OPGL in MGCs, which confirmed that MGCs participate in the process of osteolytic destruction of GCT of bone.

Central giant cell lesion

A classic case of central giant cell lesion (CGCL) is presented with emphasis on clinical, radiologic, and histologic features. The differential is discussed including peripheral giant cell granuloma, brown tumor of hyperparathyroidism, and giant cell tumor of bone. The molecular pathway of osteoclastogenesis is selectively reviewed and applied to suggest possible etiologies of the giant cell lesions. CGCL syndromes and treatment are also discussed.

The epidemiology of malignant giant cell tumors of bone: an analysis of data from the Surveillance, Epidemiology and End Results Program (1975-2004)

Malignant giant cell tumor (GCT) of bone is a rare tumor with debilitating consequences. Patients with GCT of bone typically present with mechanical difficulty and pain as a result of bone destruction and are at an increased risk for fracture. Because of its unusual occurrence, little is known about the epidemiology of malignant GCT of bone. This report offers the first reliable population-based estimates of incidence, patient demographics, treatment course and survival for malignancy in GCT of bone in the United States. Using data from the National Cancer Institute's Surveillance, Epidemiology and End Results (SEER) program, we estimated the overall incidence and determinants of survival among patients diagnosed with malignant GCT of bone from 1975–2004. Cox proportional hazards regression was used to evaluate demographic and clinical determinants of survival among malignant GCT cases. Based on analyses of 117 malignant GCT cases, the estimated annual incidence in the United States was 1.6 per 10,000,000 persons per year. Incidence was highest among adults aged 20 to 44 years (2.4 per 10,000,000 per year) and most patients were diagnosed with localized (31.6%) or regional (29.9%) disease compared to distant disease (16.2%). Approximately 85% of patients survived at least 5 years, with survival poorest among older patients and those with evidence of distant metastases at time of diagnosis. The current study represents the largest systematic investigation examining the occurrence and distribution of malignancy in GCT of bone in the general U.S. population. We confirm its rare occurrence and suggest that age and stage at diagnosis are strongly associated with long-term survival.

Telomerase activity and oncogenesis in giant cell tumor of bone

BACKGROUND

Benign giant cell tumor of bone (GCT) is a primary skeletal neoplasm with an unpredictable pattern of biologic aggressiveness and cytogenetic findings characterized by telomeric associations and telomeric reduction. The role of maintaining telomeric integrity is performed by telomerase. To determine if telomerase activity is present, cell extracts from fibroblasts and tumor cells from five patients with GCT were analyzed and compared with HeLa (a positive control cell line).

METHODS

Telomerase activity was detected by visualizing the extension of radioactive telomeric repeats on DNA sequencing gels. Telomere reduction was assessed using southern blot analyses of the restriction enzyme Hinf I digested DNA with a radio-labeled telomere probe.

RESULTS

Telomerase or telomerase-like activity was detected in the cell extracts from HeLa and tumor cells. However, GCT telomerase activity varied and was less than that observed in HeLa, but no activity was detected from fibroblasts. In addition, telomere reduction was seen in DNA isolated from both HeLa and GCT but not in fibroblasts or age-matched controls.

CONCLUSION

Telomere reduction and telomerase activity may be oncogenic sustaining events required to maintain the transformed phenotype seen in GCT.