Establishment and characterization of two novel patient-derived cell lines from giant cell tumor of bone: NCC-GCTB8-C1 and NCC-GCTB9-C1.

Giant cell tumor of bone (GCTB) is a rare osteolytic bone tumor consisting of mononuclear stromal cells, macrophages, and osteoclast-like giant cells. Although GCTB predominantly exhibits benign behavior, the tumor carries a significant risk of high local recurrence. Furthermore, GCTB can occasionally undergo malignant transformation and distal metastasis, making it potentially fatal. The standard treatment is complete surgical resection; nonetheless, an optimal treatment strategy for advanced GCTB remains unestablished, necessitating expanded preclinical research to identify appropriate therapeutic options. However, only one GCTB cell line is publicly available from a cell bank for research use worldwide. The present study reports the establishment of two novel cell lines, NCC-GCTB8-C1 and NCC-GCTB9-C1, derived from the primary tumor tissues of two patients with GCTB. Both cell lines maintained the hallmark mutation in the H3-3A gene, which is associated with tumor formation and development in GCTB. Characterization of these cell lines revealed their steady growth, spheroid-formation capability, and invasive traits. Potential therapeutic agents were identified via extensive drug screening of the two cell lines and seven previously established GCTB cell lines. Among the 214 antitumor agents tested, romidepsin, a histone deacetylase inhibitor, and mitoxantrone, a topoisomerase inhibitor, were identified as potential therapeutic agents against GCTB. Conclusively, the establishment of NCC-GCTB8-C1 and NCC-GCTB9-C1 provides novel and crucial resources that are expected to advance GCTB research and potentially revolutionize treatment strategies.

Malignant giant cell tumour of distal ulna.

Giant cell tumour (GCT) accounts for 5% of all primary bone tumours. GCT in the distal third of ulna is quite rare. We present a case of recurrent GCT in distal third of ulna with malignant features involving tenosynovium. The case was treated by wide resection of tumour and on follow up, patient recovered well with no evidence of further recurrence. Considering the features, according to the literature reviewed, is the first case of its type.

Effect of denosumab in treatment of unresectable spine and sacrum giant cell tumor of bone.

Giant cell tumor of bone (GCTB) is a rare tumor of the bone that is locally invasive. Surgery is the primary treatment that is usually done by intralesional curettage. In pelvis and spine surgery may be associated with high rate of complications, recently, Denosumab has been proposed for the treatment of these tumors in latter anatomical regions. Denosumab may be administered alone or as an adjuvant to surgery. This study aimed to assess the treatment effects of Denosumab in patients with unresectable GCTB. This study was a case series. Patients with unresectable GCTB of vertebra and sacrum were enrolled in this study. Patients received 120 mg of monthly Denosumab and additional doses on days 8th and 15th of treatment. Images of patients before and after treatment were evaluated. Nine patients with a median age of 30 years with spine and sacrum GCTB were included in this study. The median time of treatment with denosumab was 28 months (range: 3-67). Tumor control was seen in all patients. According to Inverse Choi density/size (ICDS), criteria objective response (complete response and partial response) was seen in 8 patients, and one had stable disease. Based on CT scan images, in 4 patients (44.44%), less than 50% of the transverse diameter of the tumor became ossified, and in the other five patients (55.55%), more than 50% of the tumor's transverse diameter became ossified. The median tumor volume before treatment was 829 cm3, and after treatment was 504 cm3 which was significantly reduced (P = 0.005). No complication related to therapy was seen. Tumor response was seen in all patients, and tumor control according to ICDS criteria was evident in all cases. This finding was in line with previous studies. Clinical improvement of signs and symptoms was also seen in all patients. Generally, our study demonstrates a sustained clinical benefit and tumor response with Denosumab, as tumor response ≥ 24 weeks was evident in all cases. No side effects were seen in patients despite long-term treatment with Denosumab.

Diagnosis and monitoring denosumab therapy of giant cell tumors of bone: radiologic-pathologic correlation.

OBJECTIVE: To determine the value of CT and dynamic contrast-enhanced (DCE-)MRI for monitoring denosumab therapy of giant cell tumors of bone (GCTB) by correlating it to histopathology. MATERIALS AND METHODS: Patients with GCTB under denosumab treatment and monitored with CT and (DCE-)MRI (2012-2021) were retrospectively included. Imaging and (semi-)quantitative measurements were used to assess response/relapse. Tissue samples were analyzed using computerized segmentation for vascularization and number of neoplastic and giant cells. Pearson's correlation/Spearman's rank coefficient and Kruskal-Wallis tests were used to assess correlations between histopathology and radiology. RESULTS: Six patients (28 ± 8years; five men) were evaluated. On CT, good responders showed progressive re-ossification (+7.8HU/month) and cortical remodeling (woven bone). MRI showed an SI decrease relative to muscle on T1-weighted (-0.01 A.U./month) and on fat-saturated T2-weighted sequences (-0.03 A.U./month). Time-intensity-curves evolved from a type IV with high first pass, high amplitude, and steep wash-out to a slow type II. An increase in time-to-peak (+100%) and a decrease in Ktrans (-71%) were observed. This is consistent with microscopic examination, showing a decrease of giant cells (-76%), neoplastic cells (-63%), and blood vessels (-28%). There was a strong statistical significant inverse correlation between time-to-peak and microvessel density (ρ = -0.9, p = 0.01). Significantly less neoplastic (p = 0.03) and giant cells (p = 0.04) were found with a time-intensity curve type II, compared to a type IV. Two patients showed relapse after initial good response when stopping denosumab. Inverse imaging and pathological findings were observed. CONCLUSION: CT and (DCE-)MRI show a good correlation with pathology and allow adequate evaluation of response to denosumab and detection of therapy failure.

Narlumosbart: First Approval.

Narlumosbart () is a recombinant, fully human, anti-receptor activator of nuclear factor kappa-Β ligand (RANKL) IgG4 monoclonal antibody being developed by CSPC Pharmaceutical and its wholly owned subsidiary Shanghai Jinmante Biotechnology for the treatment of giant cell tumour of bone (GCTB), bone metastases from solid tumours and osteoporosis. The RANK/RANKL signalling pathway plays a pivotal role in osteoclastogenesis and in the pathogenesis of GCTB. Narlumosbart specifically binds to RANKL and blocks the interaction of RANKL with RANK, thus inhibiting osteoclastogenesis and bone resorption by osteoclasts. In September 2023, narlumosbart received conditional first approval in China for the treatment of adults with GCTB that is unresectable or when surgical resection would result in severe functional disability. Clinical studies of narlumosbart for bone metastases, postmenopausal osteoporosis and glucocorticoid-induced osteoporosis are underway in China. This article summarizes the milestones in the development of narlumosbart leading to this first approval for the treatment of adults with GCTB.

Giant cell tumors of the distal ulna: long-term recurrence rate and functional outcomes of en bloc resection versus curettage in a multicenter study.

OBJECTIVE: The wrist is the second most commonly involved location for GCTB, while distal ulna is a relatively rare location and limited evidence exists on which surgical approaches and reconstruction techniques are optimal. We carried out a multicenter retrospective study to evaluate the recurrence rate of distal ulna GCTB and the long-term functional outcomes of different surgery options. METHODS: All 28 patients received surgical treatment for distal ulna GCTB in one of three tertiary bone tumor centers between May 2007 and January 2021 with a minimum two-year follow-up. Surgical options included intralesional curettage or en bloc resection (one of 3 types). Functional outcomes were assessed by the MSTS score, the QuickDASH instrument, MWS, and MHQ according to the latest treatment. RESULTS: Overall recurrence rate was 14.2%. The curettage group (N = 7) had a significantly higher recurrence rate compared to en bloc resection (N = 21) (42.9% vs 4.8%) (mean follow-up: 88.8 mo). Seven patients received the Darrach procedure, 5 received the original Sauvé-Kapandji procedure, and 9 received the modified Sauvé-Kapandji procedure with extensor carpi ulnaris (ECU) tenodesis. Of the 4 patients having a recurrence, 1 received the Darrach EBR, 2 received the modified Sauvé-Kapandji procedure, and 1 received resection for soft tissue recurrence. Only MWS and esthetics in the MHQ scores were different (curettage, Darrach, Sauvé-Kapandji, and Sauvé-Kapandji with ECU tenodesis [MWS: 96.5 ± 1.3 vs 91.5 ± 4.7 vs 90.8 ± 2.8 vs 91.5 ± 3.6; esthetics in MHQ: 98.5 ± 3.1 vs 89.9 ± 4.7 vs 93.8 ± 4.4 vs 92.6 ± 3.8], respectively). CONCLUSIONS: En bloc resection for distal ulna GCTB had a significantly lower recurrence rate compared with curettage and achieved favorable functional outcome scores. Given the higher recurrence rate after curettage, patients should be well informed of the potential benefits and risks of selecting the distal radioulnar joint-preserving procedure. Moreover, reconstructions after tumor resection of the ulna head do not appear to be necessary.

Does the use of polymethyl-methacrylate cement after intralesional curettage of giant cell tumors of appendicular bone guarantee reduced local recurrence rates? A retrospective analysis.

PURPOSE: Polymethyl-methacrylate cement (PMMA) is often used as bone defect reconstruction material after surgical removal of giant cell tumors. The purpose of this study was to investigate if the application of PMMA improves the local recurrence rates for giant cell tumors (GCT) of appendicular bone treated with intralesional curettage. METHODS: A retrospective analysis of all appendicular GTCs treated at two major Danish sarcoma centres between the 1st of January 1998 and December 31st 2013; minimum follow-up of 3.0 years (median: 8.9; 1.3-18.7 years). Kaplan-Meier survival model, log-rank and multivariate Cox regression were used to calculate and compare local recurrence rates. p-values <0.05 were considered statistically significant. RESULTS: 102 patients (M59/F43), median age 31Y (11-84) were included in this study. The overall 3-years local recurrence-rate was 19.9% (95%CI: 11.9-27.9%); 91% had occurred within 3 years. In patients treated with intralesional curettage (n = 64), the 3-years recurrence-rate was 30.6% (95%CI: 18.8-42.4%), compared to 2.6% (95%CI: 0.0-7.8%) in patients treated with wide resection or amputation (n = 38), p < .001. The 3-years recurrence-rate for patients treated with intralesional curettage and reconstruction using PMMA was 29.0% (95%CI: 12.6-45.4%) and without PMMA: 31.8% (95%CI: 15.2-48.4%), p = .83. CONCLUSION: We found that the use of PMMA for bone defect reconstruction after intralesional curettage of GTCs in the appendicular skeleton did not ensure a reduced risk of local recurrence.

Heat treatment for giant cell tumors of bone: A systematic review.

This systematic review evaluates the effects of heat treatments in de novo, residual and recurrent giant cell tumors of bone (GCTB). Studies were eligible for inclusion if one of the following treatments was administered: radiofrequency ablation (RFA), microwave ablation, argon cauterization, electrocauterization and hot liquid treatment. The primary outcome was recurrence. Secondary outcomes were complications, pain, function, and quality of life. Recurrence rates for microwave ablation as an adjuvant to intralesional curettage were 0%, 4% and 10% (3 retrospective single-group studies); for argon cauterization 4%, 8% and 26% (3 cohort studies); electrocauterization 0% to 33% (8 cohort studies); and hot liquid 9.5% and 24% (2 cohort studies). Follow-up was generally ≥24 months. Data on pain, function and quality of life were scarce. Complications included infection and secondary osteoarthritis. Current evidence does not demonstrate or exclude an effect of heat treatments on recurrence in GCTB. Further research should objectify if (subgroups of) patients benefit from these treatments.

DNA methylation profile discriminates sporadic giant cell granulomas of the jaws and cherubism from their giant cell-rich histological mimics.

Sporadic giant cell granulomas (GCGs) of the jaws and cherubism-associated giant cell lesions share histopathological features and microscopic diagnosis alone can be challenging. Additionally, GCG can morphologically closely resemble other giant cell-rich lesions, including non-ossifying fibroma (NOF), aneurysmal bone cyst (ABC), giant cell tumour of bone (GCTB), and chondroblastoma. The epigenetic basis of these giant cell-rich tumours is unclear and DNA methylation profiling has been shown to be clinically useful for the diagnosis of other tumour types. Therefore, we aimed to assess the DNA methylation profile of central and peripheral sporadic GCG and cherubism to test whether DNA methylation patterns can help to distinguish them. Additionally, we compared the DNA methylation profile of these lesions with those of other giant cell-rich mimics to investigate if the microscopic similarities extend to the epigenetic level. DNA methylation analysis was performed for central (n = 10) and peripheral (n = 10) GCG, cherubism (n = 6), NOF (n = 10), ABC (n = 16), GCTB (n = 9), and chondroblastoma (n = 10) using the Infinium Human Methylation EPIC Chip. Central and peripheral sporadic GCG and cherubism share a related DNA methylation pattern, with those of peripheral GCG and cherubism appearing slightly distinct, while central GCG shows overlap with both of the former. NOF, ABC, GCTB, and chondroblastoma, on the other hand, have distinct methylation patterns. The global and enhancer-associated CpG DNA methylation values showed a similar distribution pattern among central and peripheral GCG and cherubism, with cherubism showing the lowest and peripheral GCG having the highest median values. By contrast, promoter regions showed a different methylation distribution pattern, with cherubism showing the highest median values. In conclusion, DNA methylation profiling is currently not capable of clearly distinguishing sporadic and cherubism-associated giant cell lesions. Conversely, it could discriminate sporadic GCG of the jaws from their giant cell-rich mimics (NOF, ABC, GCTB, and chondroblastoma).

Histopathological response to denosumab in giant cell tumours of bone - A review of 11 cases.

Background: Giant cell tumor (GCT) of the bone is a locally aggressive primary bone tumor, that can rarely metastasize. Arising mostly in epiphysis of the long bones in young adults, the tumor is composed of mononuclear cells that are admixed with osteoclastic giant cells(OLGCs), which express RANK ligand and RANK respectively. Denosumab a monoclonal antibody against RANK ligand has been shown to reduce the tumor by causing bone lysis by inhibiting RANKL. Histological changes in 11 patients of GCT who were treated with denosumab are presented here. Materials and Methods: Clinical records and slides of 11 patients of GCT who had been administered neoadjuvant denosumab were included in the study. Evaluation of pre and post therapy GCT specimens was performed by two pathologists (RK and VM). There were 4 males and 7 females. Their mean age was 30 years. All the patients received 120 mg denosumab subcutaneously every week with additional 120 mg on days 8 and 15 of therapy. The histological slides were reviewed and following points noted: 1) degree of ossification,2) fibrosis,3) loss of osteoclastic giant cells,4) proliferation of mononuclear cells,5) atypia,6) Permeation of osteoid by malignant cells. Results: Out of 11 cases, 2 cases did not show any significant histological improvement. 7 cases showed reduction in giant cells, increased fibrosis, enhanced mononuclear cell proliferation and ossification consistent with a pathological response. Atypia and osteoid permeation were noted in 2 cases which showed transformation to osteosarcoma. Conclusion: Denosumab treated giant cell tumor show dramatic histological changes. The post therapy lesions may bear no resemblance to pretherapy lesion. There may be complete resolution or may be confused with benign or malignant lesions Rarely they may show sarcomatous transformation. It is imperative that the pathologist is aware of these changes to prevent diagnostic pitfalls as it poses therapeutic and prognostic implications.

H3F3A mutation as a marker of malignant giant cell tumor of the bone: A case report and review of literature.

Giant cell tumor of the bone (GCTB) is a locally aggressive lesion, which characteristically arises from the epimetaphyseal region of long bones. They occur commonly in the third or fourth decade of life with a slight female preponderance. Various lesions such as chondroblastoma, aneurysmal bone cysts, and nonossifying fibromas can mimic the radiologic appearance of giant cell tumors. However, the greatest challenge is to differentiate between a conventional GCTB, a malignancy arising in a giant cell tumor, and osteoclast-rich osteosarcomas. The presence of a histone gene mutation, H3F3A, involving the substitution of glycine 34 has been reported in more than 95% of GCTB. Immunohistochemical (IHC) analysis of the biopsy specimens for H3.3pG34W expression is a surrogate for gene analysis and can be used to establish the presence of GCTB. Our report is the first in Indian literature to report the use of H3.3pG34W IHC in establishing the diagnosis of a primary malignant GCTB.

Multicentric Giant Cell Tumor of Bone.

The typical presentation of giant cell tumor of bone is a solitary lesion involving the meta-epiphyseal region of the long bones. The presence of more than one distinct giant cell tumor in the same patient is rare. This study reports on 7 patients with multicentric giant cell tumor of bone. Clinical and radiologic features were reviewed to evaluate the behavior of multicentric giant cell tumor of bone. Immunohistochemistry and genetic analysis for the H3F3A gene were performed to confirm the diagnosis. The knee was most frequently involved, and most of the lesions were in an ipsilateral extremity. All of the patients received surgical management with curettage or resection. The overall median follow-up was 194 months (interquartile range, 41-336 months). Five of 7 patients had local recurrence (71%), but considering the number of surgically treated lesions, the risk of local recurrence was 33% (5 local recurrences among 15 treated lesions). No lung metastases occurred. Multicentric giant cell tumor of bone tends to exhibit the same aggressive clinical behavior as solitary giant cell tumor of bone. Patients should be monitored for the occurrence of other lesions, especially in the ipsilateral extremity. [Orthopedics. 2023;46(6):e376-e380.].

Giant cell tumor of bone in the pediatric population: a retrospective study highlighting cases of metaphyseal only location and increased local recurrence rates in skeletally immature patients.

OBJECTIVE: To describe the presentation of giant cell tumors (GCT) of the bone in the pediatric population to (1) improve the differential diagnosis of pediatric bone tumors and (2) identify the origin of GCT. Understanding the origin of bone tumors assists in establishing appropriate diagnoses and recommending treatment options. This is particularly important in children, where evaluating the need for invasive procedures is balanced with the desire to avoid overtreatment. GCT have historically been considered epiphyseal lesions with potential metaphyseal extension. Therefore, GCT may be inappropriately excluded from the differential diagnosis of metaphyseal lesions in the skeletally immature. MATERIALS AND METHODS: We identified 14 patients from 1981 to 2021 at a single institution who had histologic confirmation of GCT and were less than 18 years old at diagnosis. Patient characteristics, tumor location, surgical treatment, and local recurrence rates were collected. RESULTS AND CONCLUSIONS: Ten (71%) patients were female. Eleven (78.6%) were epiphysiometaphyseal (1 epiphyseal, 4 metaphyseal, 6 epiphysiometaphyseal). Five patients had an open adjacent physis, of which three (60%) had tumors confined solely to the metaphysis. Of the five patients with open physis, four (80%) developed local recurrence while only one patient (11%) with a closed physis had local recurrence (p value = 0.0023). Our results illustrate that for the skeletally immature, GCT can (and in our results more commonly did) occur in the metaphyseal location. These findings suggest that GCT should be included in the differential diagnosis of primary metaphyseal-only lesions in the skeletally immature.

An Arthroscopic Approach for the Intralesional Curettage of Giant Cell Tumor of the Distal Femur: A Case Report.

As a locally aggressive primary benign tumor, giant cell tumor of bone (GCTB) presents a challenge to surgeons, as it often recurs regardless of surgical resection. This report describes a case of GCTB of the distal femur in a man, aged 39 years, treated with intralesional curettage through an arthroscopic approach. A 360° view of the tumor cavity can be achieved with the help of an arthroscope, which can help complete intralesional curettage and minimize possible larger approach-related complications. The result is favorable in terms of functional outcome and recurrence after 1-year follow-up.

Preoperative denosumab treatment in patients with giant cell bone tumors in limbs: A retrospective study using propensity score matching.

BACKGROUND AND OBJECTIVES: Denosumab is recommended for advanced giant cell tumor of bone (GCTB) that is unresectable or resectable with unacceptable morbidity. But the effect of preoperative denosumab treatment on the local control GCTB remains controversial. METHODS: We conducted a study of 49 patients with GCTB in the limbs treated with denosumab before surgery and 125 patients without in our hospital from 2010 to 2017. Propensity-score matching (PSM) at a 1:1 ratio between the denosumab and control groups was performed to minimize possible selection bias, and compared the recurrence rate, limb function, and surgical degradation between the two groups. RESULTS: The 3-year recurrence rates in the denosumab group and the control group were 20.4% and 22.9% after PSM, respectively (p = 0.702). In the denosumab group, 75.5% (n = 37/49) of patients experienced surgical downgrading. Limb joint preservation rates were 92.1% (35) for 38 patients treated with denosumab and 60.2% (71) for 118 control subjects. (p ≺ 0.001). Postoperative MSTS were higher in patients in the denosumab group than in the control group (24.1 vs. 22.6, p = 0.034). CONCLUSIONS: Preoperative denosumab treatment did not result in an increased risk of local recurrence of GCTB. Patients with advanced GCTB may benefit from preoperative denosumab treatment for surgical downgrading and the preservation of the joint.

An improved total en bloc spondylectomy for L5 vertebral giant cell tumor through a single-stage posterior approach.

PURPOSE: Although total en bloc spondylectomy (TES) is strongly recommended for spinal giant cell tumor (GCT), it is extremely difficult to excise a L5 neoplasm intactly through the single-stage posterior approach. Given the risk of neurological and vascular injury, intralesional curettage (IC) is usually recommended for the treatment of L5 GCT. In this study, we presented our experience with the use of an improved TES to treat L5 GCT through the single-stage posterior approach. METHODS: This study included 20 patients with L5 GCT who received surgical treatment in our department between September 2010 and April 2021. Of them, seven patients received improved TES without iliac osteotomy, and the other 13 patients received IC (n = 8), sagittal en bloc resection (n = 1), TES with iliac osteotomy (n = 3), and TES with radicotomy (n = 1) as control. RESULTS: The mean operative time was 331.43 ± 92.95 min for improved TES group and 365.77 ± 85.17 min for the control group (p = 0.415), with the mean blood loss of 1142.86 ± 340.87 ml vs. 1969.23 ± 563.30 ml (p = 0.002). Postoperative treatment included bisphosphonates in nine patients and denosumab in 12 patients including one patient who changed from bisphosphonates to denosumab. Three patients who received IC experienced local recurrence, and no relapse was observed in improved TES group. CONCLUSION: Single-stage posterior TES for L5 GCT was previously considered impossible. In this study, we presented our experience with the use of an improved surgical technique for L5 TES through the single-stage posterior approach, which has proved to be superior to the conventional procedures in terms of blood loss control and complication and recurrence rates. LEVEL OF EVIDENCE: IV.

Significance of Histone H3.3 (G34W)-Mutant Protein in Pathological Diagnosis of Giant Cell Tumor of Bone.

OBJECTIVE: This study aimed to examine the expression of Histone H3.3 glycine 34 to tryptophan (G34W) mutant protein in Giant Cell Tumor of Bone (GCTB). METHODS: This analytic observation research used a cross-sectional study design on 71 bone tumors. The cases involved 54 tissue samples diagnosed as GCBT. It was divided into GCTB primer (n=37), recurrent GCTB (n=5), GCTB with metastasis (n=9), and malignant GCTB (n=3). There were 17 samples mimics of GCTB also tested, including chondroblastoma (n=1), giant cell reparative granuloma (n=2), giant cell of tendon sheath (n=7), chondromyxoid fibroma (n=2), aneurysmal bone cyst (n=2), and giant cell-rich osteosarcoma (n=3). The Immunohistochemistry was used to evaluate the expression of G34W-mutated protein in these bone tumors. RESULT: The representation H3.3 (G34W) was expressed in the nuclei of mononuclear stromal cells but not stained on osteoclast-like giant cells. This study was analyzed by the Chi-square test, Fisher's test, specificity test, and sensitivity test. We obtained p = 0.001 for Histone H3.3 (G34W) mutant expression in GCTB vs Non-GCTB. Statistically, there was no significant difference in the expression level of Histone H3.3 (G34W) in the GCTB and its variants p-value = 0.183. We also obtained that the specificity of Histone H3.3 expression on GCTB was 100% and the sensitivity of Histone H3.3 on GCTB was 77.8%. CONCLUSION: Histon H3.3 mutant as a mutated driver gene in an Indonesian GCTB can assist to diagnose GCTB and compare it from other bone tumors.

Giant cell tumour of bone.

Giant cell tumour of bone (GCTB) is a locally aggressive lesion that is difficult to treat as salvaging the joint can be associated with a high rate of local recurrence (LR). We evaluated the risk factors for tumour relapse after treatment of a GCTB of the limbs. A total of 354 consecutive patients with a GCTB underwent joint salvage by curettage and reconstruction with bone graft and/or cement or en bloc resection. Patient, tumour, and treatment factors were analyzed for their impact on LR. Patients treated with denosumab were excluded. There were 53 LRs (15%) at a mean 30.5 months (5 to 116). LR was higher after curettage (18.4%) than after resection (4.6%; p = 0.008). Neither pathological fracture (p = 0.240), Campanacci grade (p = 0.734), soft-tissue extension (p = 0.297), or tumour size (p = 0.872) affected the risk of recurrence. Joint salvage was possible in 74% of patients overall (262/354), and 98% after curettage alone (262/267). Of 49 patients with LR after curettage, 44 (90%) underwent repeated curettage and joint salvage. For patients treated by curettage, only age less than 30 years (p = 0.042) and location in the distal radius (p = 0.043) predicted higher LR. The rate of LR did not differ whether cement or bone graft was used (p = 0.753), but may have been reduced by the use of hydrogen peroxide (p = 0.069). Complications occurred in 15.3% of cases (54/354) and did not differ by treatment. Most patients with a GCTB can undergo successful joint salvage by aggressive curettage, even in the presence of a soft-tissue mass, pathological fracture, or a large lesion, with an 18.4% risk of local recurrence. However, 90% of local relapses after curettage can be treated by repeat joint salvage. Maximizing joint salvage is important to optimize long-term function since most patients with a GCTB are young adults. Younger patients and those with distal radius tumours treated with joint-sparing procedures have a higher rate of local relapse and may require more aggressive treatment and closer follow-up.

Single-Centre Experience Regarding the Use of Fibular Graft for Reconstruction after Resection of Grade III GCT of Distal Radius.

Background: A giant cell tumour (GCT) is a locally invasive benign tumour of bone in young adults. Treatment includes surgical resection as first-line or denosumab pharmacotherapy in inoperable patients. However, surgical resection of distal radius GCT has produced debatable functional outcomes. Here we study the use of fibular grafts for reconstruction of surgically resected GCT of the distal radius. Methods: A total of 11 patients having Grade III GCT of the distal radius were recruited for a retrospective single-centred study. Five underwent arthrodesis with fibular shaft graft and six received arthroplasty with the proximal fibula. Functional outcomes at 6 weeks, 6 and 12 months were measured by Mayo wrist score (MWS) (>51% = good) and Revised Musculoskeletal tumor society (MSTS) score (>15 = good). Results: At 6 weeks, mean MSTS score and MWS were 23.64 and 58.64% respectively, and the length of the fibular graft was a predictor for both MSTS score (p = 0.014) and MWS (p = 0.006). At 6 months, the mean MSTS and MWS were 26.36 and 76.82%, respectively. At 6 months, the surgical procedure was a predictor in MSTS score (p = 0.02) while MWS was predicted by length of graft (p = 0.02). At 12 months, MSTS score was 28.73, and MWS remained 91.82%. Length of the fibular graft was an insignificant predictor, but a significant risk factor was surgical procedure for MWS (p = 0.04) at 12 months. No variable was found significant for MSTS score. Conclusions: Resection along with reconstruction of Grade III GCT of the radius with fibular graft was found an optimal treatment option. Also, use of the fibular head grafts and shorter length grafts are predictors for better outcomes after surgery. Level of Evidence: Level IV (Therapeutic).