How safe and effective is denosumab for bone giant cell tumour?

Central giant cell granuloma of the jaws-long-term clinical and radiological outcomes of surgical and pharmacological management

OBJECTIVES

To compare long-term results of different treatment modalities in central giant cell granuloma of the maxillofacial-skeleton. Primary resection may result in major defects. Alternative treatments include pharmacological agents. As yet there has been no consensus on the use of the variety of treatment options, and few studies have reported clarifying long-term results.

MATERIALS AND METHODS

This retrospective study on 22 patients with 25 lesions evaluated clinical, radiological and histological features, treatment preformed and lesion recurrence. Success was defined as regression/calcification and failure as recurrence, progression or un-responsiveness.

RESULTS

Of the presenting patients, 77% were under age 40. Lesion prevalence was higher in the anterior mandible and left posterior maxilla. Most cases exhibited pain, tooth-mobility or mucosal-expansion. The appearance was predominantly unilocular in the maxilla and multilocular in the mandible, which also exhibited higher prevalence of cortical perforation. Up to 80% of lesions were classified as aggressive. Intralesional steroids/calcitonin were used in 7 cases. Mean follow-up was 39.8 months. Two cases showed recurrence. In 71% of the cases treated pharmacologically, calcification/regression were observed.

CONCLUSIONS

Our analysis indicates better outcomes using a combined approach, including both pharmacological and surgical treatments in large aggressive lesions. Pharmacological treatment resulted in decreased size or well-defined lesions, thus reducing the need for extensive bone resection. Dual treatment with corticosteroids and calcitonin showed no superior outcomes, but a larger cohort should be assessed.

CLINICAL RELEVANCE

There are several protocols for treatment of central-giant-cell-granuloma lesions, but most are not fully established. It is important to report results that contribute to the establishment of proven protocols. This report attempts to establish the relevance of the combined approach: pharmacological treatment followed by surgical resection.

[Giant cell tumor of bone-an update]

In the past few years, numerous new insights have been gained in the field of giant cell tumor of bone (GCTB). On the one hand, the detection of the highly characteristic histone mutation in the H3F3A gene in GCTB is becoming increasingly important in diagnostics in differentiating GCTB from other giant cell-rich lesions of bone as well as for defining rare variants of GCTB without osteoclastic giant cells. On the other hand, the effects of the H3F3A mutation were shown to have an impact on the epigenetic profile of tumor-driving stromal cells, providing new insights into tumorigenesis of GCTB.

Denosumab in Giant Cell Rich Tumors of Bone: An Open-Label Multicenter Phase II Study

BACKGROUND

Since giant cell tumors of bone (GCTB) and other giant cell rich tumors of bone (GCRTB) share the histological presence of osteoclastic giant cells and expression of RANK/RANKL, we hypothesized that GCRTB will respond similarly to denosumab as GCTB. The primary objective of this study was to determine the efficacy of denosumab in patients with GCRTB that have recurred or require morbid surgery.

METHODS

In this open-label, multicenter, phase II trial, patients with GCRTB were included (June 2018-March 2020). Recruitment was stopped because of low accrual. Patients received denosumab (120 mg) subcutaneously (SC) on day 1 of every 4-week cycle with a loading dose of 120 mg SC on days 8 and 15.

RESULTS

Three patients were enrolled. One withdrew consent before start of study. The remaining patients had central giant cell granuloma of the jawbone (CGCG). Median treatment duration was 15 cycles (range 12-18). In both subjects, improvement in ossification of lesions was seen. Median follow-up was 28.5 months (range 20-37). One patient developed a recurrence for which surgery was performed.

CONCLUSION

Due to critical emerging real-world data of denosumab in GCRTBs, the study was prematurely stopped and not supportive of use of denosumab for this indication. (ClinicalTrials.gov Identifier: NCT03605199).

Denosumab for giant cell tumors of bone from 2010 to 2022: a bibliometric analysis

Giant cell tumors of the bone (GCTB) are considered moderately malignant bone tumors. Denosumab, as a neoadjuvant therapy, provides new possibilities for treating GCTB. However, even after multiple studies and long-term clinical trials, there are limitations in the treatment process. Research data and Medical Subject Headings terms related to denosumab and GCTB were collected from January 2010 to October 2022 using the Web of Science and MeSH ( https://meshb.nlm.nih.gov ) browsers. These data were imported into CiteSpace and VOSviewer softwares for bibliometric analysis. Overall, 445 publications on denosumab and GCTB were identified. Over the last 12 years, the growth rate of the total number of publications has remained relatively stable. The USA published the highest number of articles (83) and had the highest centrality (0.42). Amgen Inc. and Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) First Ortoped Rizzoli were identified as the most influential institutions. Many authors have made outstanding contributions to this field. Lancet Oncology had the highest journal impact factor (54.433). Local recurrence and drug dosage are current research hotspots, and future development trends will mainly focus on prognostic markers of GCTB and the development of new therapies. Further research is required to analyze denosumab's safety and efficacy and understand its local recurrence of GCTB, to identify the optimal dose. Future progress in this field will likely focus on exploring new diagnostic and recurrence markers to monitor disease progression and examine new therapeutic targets and treatment strategies.

Conversion in a Resectable Tumor after Denosumab Neoadjuvant in a Large Dorsal Giant Cells Tumor: A Case Report and a Literature Review

Giant cell tumors of bone are a rare entity, usually occurring in young patients and characteristically arising in the long bones. The spinal location is rare and usually presents with pain and/or neurological symptoms. The treatment of choice is surgery. Treatment with Denosumab, a bisphosphonate inhibitor of RANK-L, which is highly expressed in these tumors, has shown extensive activity in unresectable patients or those undergoing incomplete surgery. Preoperative treatment with this drug is gaining increasing interest, as its high potency in tumor reduction in this subtype of neoplasm has allowed resectability in selected patients. We present the case of a young patient with a large spinal tumor who, after neoadjuvant Denosumab, underwent complete en bloc surgery with clean margins and a great pathological response.

Proximal Tibia Tumour Location and Curettage Are Major Risk Factors of Local Recurrence in Giant Cell Tumour of Bone

Giant cell tumour of bone (GCTB) is one of the most common local aggressive tumourous lesions with a wide variety of biological behaviour. However, there are no clear indicative criteria when choosing the type of procedure and the complication rates remain high, especially in terms of local recurrence. The purpose of the study was to (1) identify the main risk factors for local recurrence, (2) evaluate the recurrence-free survival in dependence on neoadjuvant denosumab use and the type of procedure, and (3) compare the functional outcomes after curettage and en bloc resection. The group included 102 patients with GCTB treated between 2006 and 2020. The mean age of patients was 34.4 years (15-79). The follow-up period was 8.32 years (2-16) on average. Local recurrence occurred in 14 patients (29.8%) who underwent curettage and in 5 patients (10.6%) after en bloc resection. Curettage was shown to be a factor in increasing recurrence rates (OR = 3.64 [95% CI: 1.19-11.15]; p = 0.023). Tibial location was an independent risk factor for local recurrence regardless of the type of surgery (OR = 3.22 [95% CI: 1.09-9.48]; p = 0.026). The recurrence-free survival rate of patients treated with resection and denosumab was higher compared to other treatments at five years postoperatively (p = 0.0307). Functional ability and pain as reported by patients at the latest follow-up were superior after curettage compared to resection for upper and lower extremity (mean difference: -4.00 [95% CI: -6.81 to -1.18]; p < 0.001 and mean difference: -5.36 [95% CI: -3.74 to -6.97]; p < 0.001, respectively). Proximal tibia tumour location and curettage were shown to be major risk factors for local recurrence in GCTB regardless of neoadjuvant denosumab treatment. The recurrence-free survival rate of patients treated with resection and denosumab was higher compared to other treatments. The functional outcome of patients after curettage was better compared to en bloc resection.

The Role of Denosumab in the Treatment of Primary Tumors of Bone

Many hand surgeons treat benign bone tumors without referral to orthopedic oncologists. However, there have been considerable advances in medical therapy for some of these tumors, with which hand surgeons may not be as familiar. This review focuses on the mechanism and uses of denosumab in the treatment of benign tumors of bone. Although the hand surgeon may not be directly prescribing this therapy, they are often the only physician treating the patient for these conditions. As such, awareness regarding the use of this therapy in reducing pain, decreasing tumor volume, and treatment of potential lung metastases is critical to those taking on these cases without the support of an orthopedic oncologist. This article aims to familiarize hand surgeons with denosumab to help promote knowledge of this therapeutic option and the potential role of this medication in the treatment of primary bone tumors in the hand.

Current therapies and future prospective for locally aggressive mesenchymal tumors

Locally aggressive mesenchymal tumors comprise a heterogeneous group of soft tissue and bone tumors with intermediate histology, incompletely understood biology, and highly variable natural history. Despite having a limited to absent ability to metastasize and excellent survival prognosis, locally aggressive mesenchymal tumors can be symptomatic, require prolonged and repeat treatments including surgery and chemotherapy, and can severely impact patients' quality of life. The management of locally aggressive tumors has evolved over the years with a focus on minimizing morbid treatments. Extensive oncologic surgeries and radiation are pillars of care for high grade sarcomas, however, play a more limited role in management of locally aggressive mesenchymal tumors, due to propensity for local recurrence despite resection, and the risk of transformation to a higher-grade entity following radiation. Patients should ideally be evaluated in specialized sarcoma centers that can coordinate complex multimodal decision-making, taking into consideration the individual patient's clinical presentation and history, as well as any available prognostic factors into customizing therapy. In this review, we aim to discuss the biology, clinical management, and future treatment frontiers for three representative locally aggressive mesenchymal tumors: desmoid-type fibromatosis (DF), tenosynovial giant cell tumor (TSGCT) and giant cell tumor of bone (GCTB). These entities challenge clinicians with their unpredictable behavior and responses to treatment, and still lack a well-defined standard of care despite recent progress with newly approved or promising experimental drugs.

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.

Custom-Made 3D-Printed Prosthesis after Resection of a Voluminous Giant Cell Tumour Recurrence in Pelvis

Giant-cell tumours are benign aggressive bone lesions that can affect any part of the skeleton. In early stages, curettage is preferred, but in case of local recurrence or voluminous lesions in the periacetabular region, wide resection and reconstruction are recommended. The purpose of this article is to increase clinicians' awareness of the importance of the follow-up of these patients and to describe a case of a voluminous recurrence of a giant-cell tumour in the pelvis. We present a 25-year-old female who underwent internal hemipelvectomy assisted by 3D cutting-guides and reconstruction with a custom-made 3D-printed pelvic prosthesis, hip arthroplasty and ilio-sacral arthrodesis. No postoperative complications occurred and, at long-term follow-up, the patient had a stable and painless hip joint, good bone-implant osteointegration, with an excellent functional outcome. In spite of all available reconstructive techniques, in well-selected patients with voluminous pelvic resections, custom-made 3D-printed implants allow patients to have a good mechanical outcome.

En Bloc Resection With Reconstruction Using a Customized Megaprosthesis in a Case of Proximal Humerus Giant Cell Tumor: A Case Report

A giant cell tumor is a common, benign but locally aggressive bone tumor faced by orthopedic surgeons. The proximal humerus is a rare site of occurrence for this tumor, and the challenges posed while approaching such a case are discussed in this report of a 29-year-old male who presented with pain, swelling, and restricted motion at the left shoulder. Plain radiographs and MRI were suggestive of an aggressive giant cell tumor of the proximal humerus, which was confirmed on histopathological examination. Due to the lesion's extensive soft-tissue involvement, en-bloc resection with reconstruction was planned, but due to the COVID-19 pandemic, surgery was delayed. During the same period, the patient had trivial trauma to the same shoulder, following which the size of the lesion began increasing. The patient was operated on with en-bloc resection and reconstruction with a custom megaprosthesis; following the surgery, there was a complete resolution of pain and improvement in the range of motion. En bloc resection and replacement with a customized megaprosthesis, though technically demanding, offer a safe and cost-effective modality for limb salvage surgery for large giant cell tumors, with good functional outcomes and decreased chances of recurrence.

Progress on Denosumab Use in Giant Cell Tumor of Bone: Dose and Duration of Therapy

Giant cell tumor of bone (GCTB) is an aggressive non-cancerous bone tumor associated with risks of sarcoma and metastasis. Once malignancy occurs, the prognosis is generally poor. Surgery remains the main treatment for GCTB. Multidisciplinary management is a feasible option for patients wherein surgical resection is not an option or for those with serious surgery-related complications. Denosumab is an anti-nuclear factor kappa B ligand approved for the treatment of postmenopausal women with osteoporosis, bone metastases, and advanced or inoperable GCTB. However, the guidelines for treating GCTB are unclear; its short-term efficacy and safety in inoperable patients have been demonstrated. Lengthier therapies (high cumulative doses) or pre-operative adjuvant therapy may be associated with severe complications and high local recurrence rates. Short-term administration helps attain satisfactory local control and functionality. As a result, lately, the impact of different doses and lengths of treatment on the efficacy of denosumab in GCTB treatment, the incidence of complications, and recurrence rates have gained attention. The efficacy and safety of denosumab against GCTB, its impact on imaging assessment, related complications, and recurrence of GCTB were previously reviewed. For further research direction, this paper reviews the progress of studies evaluating the impact of the dose and duration of denosumab therapy for GCTB.

Bioactive glass selectively promotes cytotoxicity towards giant cell tumor of bone derived neoplastic stromal cells and induces MAPK signalling dependent autophagy

Giant cell tumors of bone (GCTB) are associated with massive bone destructions and high recurrence rates. In a previous study, we observed cytotoxic effects of three different compositions of bioactive glasses (BGs) towards GCTSC but not bone marrow derived stromal cells (BMSC) indicating that BGs represent promising candidates for the development of new therapeutic approaches. In the current study we aimed to investigate the molecular mechanisms that are involved in BG induced cytotoxicity. We observed, that BG treatment was not associated with any signs of apoptosis, but rather led to a strong induction of mitogen activated protein kinases (MAPK) and, as a consequence, upregulation of several transcription factors specifically in GCTSC. Genome wide gene expression profiling further revealed a set of fifteen genes that were exclusively induced in GCTSC or induced significantly stronger in GCTSC compared to BMSC. BG treatment further induced autophagy that was significantly more pronounced in GCTSC compared to BMSC and could be inhibited by MAPK inhibitors. Together with the known osteogenic properties of BGs our findings support the suitability of BGs as therapeutic agents for the treatment of GCTB. However, these data have to be verified under in vivo conditions.

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Bioactive glasses (BG) are selectively cytotoxic towards neoplastic stromal cells.

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BG induced cell death is independent from apoptosis.

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BG activates mitogen activated protein kinases and transcription factors.

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BG trigger differential gene expression in neoplastic versus normal cells.

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BG induce autophagy.

Study of imaging changes following preoperative denosumab for giant cell tumor of bone

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The preoperative application of denosumab can reduce tumor blood supply.

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The decrease of blood supply was the most significant in the initial stage of treatment.

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It is not recommended to apply denosumab long before surgical treatment.

Background

The changes in the characteristics of the tumor blood supply of giant cell tumor of bone over time after treatment with denosumab remain unclear. The purpose of this study was to evaluate the change in the blood supply imaging characteristics of giant cell tumor of bone after preoperative denosumab treatment and to provide evidence for evaluating the reasonable time for preoperative treatment.

Methods

A total of 59 patients with giant cell tumor of bone who were treated in our hospital from 2014 to 2019 were enrolled in the study. All patients underwent enhanced CT examination of the tumor site before denosumab treatment and every month after treatment. The plain CT value and enhanced CT value of the tumor were measured, and the CT enhancement rate of the tumor was calculated. The change in the CT enhancement rate of the tumor over time after denosumab treatment was analyzed.

Results

The average tumor enhancement rates were 2.14 (1.22–4.05), 1.60 (1.12–2.53), 1.38 (1.02–2.24), and 1.25 (1–2.11) before denosumab treatment and one month, three months, and six months after treatment, respectively. After denosumab treatment, the average monthly CT enhancement rate decreased as follows: 0.54 (25.2%) in the first month, 0.11 (5.15%) in the second to third months, and 0.04 (1.87%) in the fourth to sixth months. The tumor enhancement rate was no longer significantly reduced three months post-treatment. There was a significant correlation between the reduction in the CT enhancement rate and the initial CT enhancement rate (P = 0.000).

Conclusion

The preoperative application of denosumab can reduce tumor blood supply. The decrease in the blood supply is the most significant in the initial stage of treatment. Following treatment, the decrease in the blood supply gradually reduces over time. Therefore, for the purpose of reducing intra-operative bleeding and facilitating surgery, application of denosumab treatment is not recommended more than three months before surgery.

Osteosarcoma in Children: Not Only Chemotherapy

Osteosarcoma (OS) is the most severe bone malignant tumor, responsible for altered osteoid deposition and with a high rate of metastasis. It is characterized by heterogeneity, chemoresistance and its interaction with bone microenvironment. The 5-year survival rate is about 67% for patients with localized OS, while it remains at 20% in case of metastases. The standard therapy for OS patients is represented by neoadjuvant chemotherapy, surgical resection, and adjuvant chemotherapy. The most used chemotherapy regimen for children is the combination of high-dose methotrexate, doxorubicin, and cisplatin. Considered that the necessary administration of high-dose chemotherapy is responsible for a lot of acute and chronic side effects, the identification of novel therapeutic strategies to ameliorate OS outcome and the patients' life expectancy is necessary. In this review we provide an overview on new possible innovative therapeutic strategies in OS.

Late Local Recurrence of Bone Giant Cell Tumors Associated with an Increased Risk for Malignant Transformation

Simple Summary

In giant cell tumor of bone (GCTB), an intermediate malignant bone tumor, approximately 4% of cases can undergo malignant transformation. We analyzed risk factors for malignant transformation of GCTB treated without radiotherapy and retrospectively reviewed medical files of 461 patients with GCTB of the extremities who had undergone surgery alone, with no radiotherapy or denosumab therapy. Malignant transformation occurred in 15 of 461 patients (3.3%) at a median follow-up period of 192 months. The median follow-up duration was 89.4 months. Multivariate analysis revealed that local recurrence was an independent prognostic factor for unfavorable malignant transformation. The interval between the last surgery to local recurrence and malignant transformation was longer than that to local recurrence of benign GCTB, with a median of 15.2 (IQR, 5.2–25.4) years versus 1.3 (IQR, 0.8–2.6) months, respectively (p < 0.001). Late local recurrence of GCTB is associated with a higher risk of malignant transformation.

Abstract

In giant cell tumor of bone (GCTB), an intermediate malignant bone tumor, approximately 4% of all cases undergo malignant transformation. Accordingly, we analyzed risk factors for malignant transformation of GCTB treated without radiotherapy. We retrospectively reviewed medical records of 530 patients with GCTB of the extremities, admitted and treated at two institutions between January 1980 and December 2019. Overall, 4 patients with primary malignant GCTB, 4 patients with missing data, 3 patients with a history of radiotherapy, 22 patients with a follow-up of less than 6 months, and 36 patients who received denosumab were excluded. Accordingly, 461 patients were included for further analysis. Malignant transformation was observed in 15 of 461 patients (3.3%) at a median follow-up period of 192 months. The median follow-up duration was 89.4 months. Multivariate analysis revealed that local recurrence was an independent prognostic factor for unfavorable malignant transformation (Hazard ratio [HR], 11.33; 95% confidence interval [CI] 2.33–55.13; p = 0.003 for once versus none and HR, 11.24; 95% CI, 1.76–71.96; and p = 0.011 for twice or more versus none). The interval between the last surgery to local recurrence and malignant transformation was longer than that to local recurrence of benign GCTB, with a median of 15.2 years (interquartile range [IQR], 5.2–25.4) versus 1.3 months (IQR, 0.8–2.6), respectively (p < 0.001). Late local recurrence of GCTB is associated with a higher risk of malignant transformation.

Denosumab for Effective Tumor Size Reduction in Patients With Giant Cell Tumors of the Bone: A Systematic Review and Meta-Analysis

BACKGROUND

Denosumab is a human monoclonal antibody that has been used successfully in the treatment of giant cell tumors of bone. These tumors are rare and, in principle, benign, but they are highly aggressive, locally advanced, osteolytic bone tumors that can metastasize to the lungs. Denosumab is an effective treatment when these tumors cannot be surgically removed or when surgical resection is likely to lead to severe morbidity (eg, loss of limbs or joints). The aim of this systematic review and meta-analysis was to investigate patients with giant cell tumors of bone who experienced tumor progression during treatment with denosumab and to compare them with patients who experienced reduction of their giant cell tumors of bone during treatment with denosumab.

METHODS

Embase, Cochrane Library, and MEDLINE/PubMed databases were searched for trials submitted by January 7, 2020, that reported the efficacy and safety of denosumab in patients with giant cell tumors of bone.

RESULTS

Sixty studies were reviewed, involving a total of 1074 patients who had giant cell tumors of bone and were treated with denosumab. Of the 60 studies, 58% of the patients were from case series studies, 39% from open-label phase II studies, and 3% from case reports. The response rate for denosumab as a treatment for giant cell tumors of bone was 97.5%, with statistical significance (P < .0001). Pain in the limbs was statistically the most common adverse event for denosumab treatment in case series studies (P < .0001). No treatment-related deaths occurred in the reviewed studies.

CONCLUSION

Cumulative evidence supports the addition of surgery to optimal medical therapy with denosumab to reduce tumor size, clinical symptoms, and mortality among patients with giant cell tumors of bone.

The Role of Denosumab for Surgical Outcomes in Patients with Giant Cell Tumour of Bone: A Systematic Review

Background: The role of denosumab in patients with resectable giant cell tumour of bone remains unclear. We asked the following research question: for patients (aged ≥ 12 years) with resectable giant cell tumour of bone, what are the benefits and harms of denosumab compared with no denosumab in terms of (1) facilitation of surgery (operative time, blood loss), (2) disease recurrence, (3) pain control, (4) disease stability, and (5) adverse effects (e.g., malignant transformation, osteonecrosis of jaw, atypical femur fracture)? One previous systematic review addressed only one outcome-disease recurrence. Therefore, we undertook this new systematic review to address the above five outcomes. Methods: MEDLINE, EMBASE, PubMed, and Cochrane Database of Systematic Reviews databases were searched on June 30, 2020. Results: This systematic review included one previous systematic review and five comparative studies. Due to poor quality, non-randomized studies fraught with selection bias, it is difficult to determine if a significant difference exists in the outcomes for surgical giant cell tumour of bone with perioperative denosumab. There were no reported cases of adverse effects from denosumab. Conclusion: To date, there is insufficient evidence to understand the value of denosumab in the perioperative setting in patients with giant cell tumour of bone.

Immunohistochemical Characterization of Giant Cell Tumor of Bone Treated With Denosumab: Support for Osteoblastic Differentiation

Giant cell tumor of bone is a locally aggressive, rarely metastasizing neoplasm. Evidence suggests that the neoplastic cells may be osteoblastic in differentiation. Standard treatment is surgical removal, but medical therapy with denosumab, an inhibitor of receptor activator of nuclear factor-κβ ligand, has become a component of patient management in select cases. Denosumab-treated giant cell tumor of bone (DT-GCTB) shows drastic morphologic changes including the presence of abundant bone. To further determine the relationship of the neoplastic cells to osteoblast phenotype, we performed a morphologic and immunohistochemical study on a series of DT-GCTB. Cases of DT-GCTB were retrieved from surgical pathology files, available slides were reviewed, and immunohistochemistry for H3.3 G34W, SATB2, and p63 was performed. The cohort included 31 tumors from 30 patients (2:3 male:female), ages 15 to 73 years (median=36 y). The morphology of post-denosumab-treated tumors ranged from tumors composed of an abundant bone matrix with few spindle cells to spindle cell-predominant tumors. Five had focal residual classic CGTB, and 2 manifested mild nuclear atypia. The majority expressed all markers: 86.2% for H3.3 G34W, 96.7% for SATB2, and 100% for p63. All markers stained the various tumor components including spindle cells and the cells on the surface of and within the treated tumor bone matrix. Most markers were also positive in reactive-appearing woven bone adjacent to tumor: 84.6% for H3.3 G34W, 100% for SATB2, and 68% for p63. These findings suggest that denosumab treatment of giant cell tumor of bone results in osteoblastic differentiation with bone production.

Chondroblastoma Expresses RANKL by RNA In Situ Hybridization and May Respond to Denosumab Therapy

Lesions of bone featuring osteoclast-like giant cells comprise a diverse group of entities, including giant cell tumor (GCT) of bone, chondroblastoma, and aneurysmal bone cyst, among others. The receptor activator of nuclear factor-κB ligand (RANKL) has been implicated in the pathogenesis of GCT of bone and may play a role in the pathogenesis of other giant cell-rich lesions as well. In addition, RANKL inhibitors (denosumab) have also been shown to have some efficacy in treating some giant cell-rich lesions. Herein, we examine RANKL expression by RNA in situ hybridization in a total of 84 osseous lesions with a focus on chondroblastoma, GCT, fibrous dysplasia, and aneurysmal bone cyst. The lesions were tested for RANKL expression using a chromogenic RNA in situ hybridization assay. RANKL expression was identified in 24/25 (96%) GCT, 24/26 (92%) chondroblastomas, 6/7 (86%) aneurysmal bone cysts, and 3/16 (19%) patients with fibrous dysplasia. RANKL expression was statistically lower in chondroblastoma and aneurysmal bone cyst compared with GCT. RANKL reactivity in fibrous dysplasia was exclusively seen in the 3 cases with osteoclast-type giant cells. Our results indicate a high proportion of chondroblastomas, GCTs, and aneurysmal bone cysts express RANKL while reactivity in fibrous dysplasia is dependent on the presence of osteoclast-type giant cells. On the basis of the success of denosumab therapy for GCTs, our results indicate that it may be a potential therapeutic option in other primary osseous tumors.

Pulmonary metastasis of giant cell tumour: a retrospective study of three hundred and ten cases

BACKGROUND

Giant cell tumour (GCT) is an invasive benign bone tumour, and the incidence of pulmonary metastasis is rare. We are aiming to analyze risk factors of pulmonary metastasis and clinical prognosis for giant cell tumour patients with pulmonary metastasis.

METHOD

We performed a retrospective study of 310 patients with GCT between December 2004 and December 2016. Risk factors of pulmonary metastasis were analyzed by univariate and multivariate logistic regression analysis. Then, the influence of risk factors of overall LR (local recurrence), recurrent tumor at presentation, LR after our therapy, and with soft tissue mass on the pulmonary metastasis-free survival rates was analyzed.

RESULTS

The mean follow-up of the present cohort was 45.6 ± 35.3 months (median, 36.6 months; range, 6.1-193.4 months). Eighteen (5.8%) of 310 patients developed pulmonary metastasis. The average interval from surgery of primary tumour to detection of pulmonary metastasis was 15 months. Multivariate logistic regression analysis showed overall local recurrence was the independent risk factor of developing pulmonary metastasis. Among 18 patients with pulmonary metastasis, sixteen cases had history of local recurrence (88.9%, 16/18), including eleven (68.8%, 11/16) with local recurrence at presentation before receiving our therapy and seven (43.8%, 7/16) with local recurrence after receiving treatment in our hospital. Time to local recurrence had obvious difference between patients with and without pulmonary metastasis. Patients with pulmonary metastasis were prone to recur earlier. Furthermore, overall local recurrence, local recurrence after our therapy, recurrent tumor at presentation, and tumour with a soft tissue mass showed statistical differences in the pulmonary metastasis-free survival rates.

CONCLUSIONS

Giant cell tumour patients with soft tissue mass and overall local recurrence are prone to develop pulmonary metastasis. Although giant cell tumour is a benign tumor, more attention should be paid to the problem of pulmonary metastatic lesions, and chest CT scan should be recommended during follow-up.

Malignancy in giant cell tumor of bone in the extremities

Background

Malignancy in giant cell tumor of bone (GCTB) is a rare tumor with relevant literature being sparse. In primary malignant GCTB, distinct areas of benign GCTB are juxtaposed with high-grade sarcoma, while in secondary malignant GCTB sarcoma occurs at the site of previously managed GCTB. This study assesses the distinguishing characteristics of patients with this condition, the time interval for development of secondary malignant GCTB, the outcome of treatment, and explores factors associated with oncologic outcomes.

Methods

This is a retrospective case series of patients from a prospectively collected institutional musculoskeletal oncology database. From January 1998 to December 2016, 1365 patients were managed for extremity GCTBs. 32 (2.3%) patients had malignant GCTB, including 12 with primary malignant GCTB and 20 with secondary malignant GCTB. The study population comprised 18 males and 14 females presenting at a mean age of 33.7 years (±13.0) and followed for a mean of 9.5 years (±7.4). Data were collected on patient and treatment-related factors, and the occurrence of local recurrence, metastasis, and death. The time from the diagnosis of GCTB to the secondary malignant GCTB was defined as the latent period.

Results

Malignant GCTB most commonly presents in the distal femur and proximal tibia with pain and swelling. Radiologically, they are aggressive Campanacci Grade III tumors with prominent bony destruction and soft tissue extension. In the 20 patients with secondary malignant GCTB, the tumors were osteosarcoma in 15, undifferentiated pleomorphic sarcoma in 4 patients and fibrosarcoma in one patient. The mean latent period in patients with secondary malignant GCTB was 7.9 year (±7.3). The median recurrence-free survival (RFS) of secondary malignant GCTB (latent period) and benign GCTB were 61.5 and 19 months respectively (p < 0.001), receiver operating curve analysis found 49.5 months to be the critical threshold, with a longer interval to recurrence being seen in malignant recurrence. The 5 and 10-year overall survival rate of malignant GCTB were 45.8% and 36.1% respectively. The 5-year survival rates of primary malignant GCTB and secondary malignant GCTB were 56.2% and 40.0% respectively (p = 0.188). Adequate surgical margins decreased the local recurrence (LR) rate (P = 0.006). Pulmonary metastasis developed in 69% of patients. The median distant metastasis-free survival between malignant GCTB and benign GCTB were 9 and 21 months (p = 0.002). Chemotherapy was associated with a longer pulmonary metastasis free survival (13 months Vs 6 months, P = 0.002), but not with increased overall survival (57.0% Vs 33.3%, P = 0.167).

Conclusions

Malignant GCTB carries a poor prognosis. Accurate diagnosis is critical to avoid inadequate surgical margins when treating primary malignant GCTB. Aggressive tumors and pulmonary metastasis should raise suspicion for malignant GCTB. Secondary malignant transformation should be suspected in patients presenting with recurrence especially after 4 years. Adjuvant chemotherapy use did not benefit survival, but was associated with increased pulmonary progression-free survival.

Is a Short-course of Preoperative Denosumab as Effective as Prolonged Therapy for Giant Cell Tumor of Bone?

BACKGROUND

Denosumab is an inhibitor of monoclonal receptor activator of nuclear factor-ĸB ligand, approved to treat giant cell tumors of bone (GCTB). It is commonly used for unresectable tumors and for downstaging the tumor to perform less-morbid procedures. Although denosumab has been used extensively for GCTBs, there are no recommendations regarding the duration of therapy. The risk factors associated with local recurrence (LR) in patients receiving preoperative denosumab for GCTB also are unknown.

QUESTIONS/PURPOSES

(1) Is short-course (three doses or fewer) preoperative denosumab treatment as effective as longer course (more than three doses) of treatment in terms of achieving a clinical, radiologic, and histologic response in patients with GCTB? (2) Is there an increased risk of LR after short-course denosumab therapy compared with long-course denosumab therapy; and after controlling for confounding variables, what factors were associated with LR after surgery for GCTB in patients receiving preoperative denosumab?

METHODS

A retrospective study was performed using an institutional database of 161 skeletally mature patients with a histologic diagnosis of GCTB who received denosumab between November 2010 and July 2019 to downstage the tumor before surgery. In general, we used denosumab when we thought it would facilitate either resection or curettage (by formation of a sclerotic rim around the osteolytic lesion), when a less-morbid procedure than initially planned might be performed, and in patients with complex presentations like cortical breech and soft tissue extension, pathological fracture, thinning of more than three cortices of the extremity. From 2010 to late 2015, denosumab was administered for approximately 4 to 6 months; starting in late 2015 through 2020, the number of denosumab doses has been reduced. We divided patients into two groups: Those who received three or fewer doses of denosumab (short-course, n = 98) and those who received more than three doses of denosumab (long-course, n = 63). Comparing those in the long-course group with those in the short-course group whose procedures were performed at least 2 years ago, there were no differences in loss to follow-up before 2 years (3% [3 of 98] versus. 3% [2 of 63]). The mean patient age was 30 years (± 6.1) and the mean number of denosumab doses was 4.4 (range 1 to 14). Overall, 77% (37 of 48) of patients taking short-course denosumab and 75% (27 of 36) of patients on long-course denosumab underwent curettage, and the remaining patients with an inadequate bony shell around the tumor or destruction of articular cartilage in both groups underwent tumor resection. With the numbers available, the patients with short- and long-course denosumab were not different in terms of age, sex, MSTS score on presentation, lesion size, lesion location, Campanacci grade, presence of pathological fracture and pulmonary metastasis on presentation, and the type of surgery performed (curettage versus resection). We analyzed the change in the Musculoskeletal Tumor Society score, change in Campanacci grade, radiologic objective tumor response (defined as a partial or complete response, per the modified inverse Choi criteria), and histologic response (defined as reduction of more than 90% of osteoclast-like giant cells or a reduction of more than 50% of mesenchymal spindle-like stromal cells, along with evidence of lamellar or woven bone formation, when compared with the biopsy sample) between the two groups (short- and long-course denosumab). LR rates were compared between the two groups, and after controlling for confounding variables, factors associated with LR in all operated patients were analyzed with a Cox proportional hazards regression analysis.

RESULTS

With the numbers available, there was no difference between the short- and long-course denosumab groups in terms of mean percentage improvement in MSTS score (20 [± 18.5] versus 24 [± 12.6]; p = 0.37), radiologic objective tumor response (90% [43 of 48] versus 81% [29 of 36]; p = 0.24) and histologic response (79% [38 of 48] versus 83% [30 of 36]; p = 0.81). With the numbers available, there was no difference between the short- and long-course denosumab groups in terms of Kaplan-Meier survivorship free from LR at 5 years after surgery (73% [95% confidence interval, 68 to 76] versus 64% [95% CI 59 to 68]; log-rank p = 0.50). After controlling for potential confounding variables like age, sex, Campanacci grade and MSTS score on presentation, number of denosumab doses administered before surgery, clinical, radiologic and histologic response to denosumab, and time duration between denosumab therapy and surgery, we found that tumors involving the bones of the hand and the foot (hazard ratio 7.4 [95% CI 2.0 to 27.3]; p = 0.009) and curettage (HR 6.4 [95% CI 2.8 to 23.0]; p = 0.037) were independently associated with a higher risk of LR.

CONCLUSIONS

In this preliminary, single-center study, we found that a short-course of preoperative denosumab (three or fewer doses) was associated with no differences in clinical scores, histological and radiological response, or LR-free survivorship, compared with longer-course of denosumab (more than three doses). Fewer preoperative doses can reduce the complications and costs associated with more-prolonged therapy. Denosumab must be used cautiously before curettage for GCTB, and only if the benefit of joint salvage outweighs the possibility of LR. However, given the small number of patients, potentially clinically important differences might have been missed, and so our findings need to be confirmed by larger, multicenter, prospective trials.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Giant cell tumors of the sacrum: is non-operative treatment effective?

PURPOSE

Giant cell tumors of sacrum in which surgery could endanger important neural components were treated with short term denosumab, angioembolisation and radiotherapy in different combinations to provide a non-operative function preserving treatment option.

METHODS

Between April 2013 and April 2017, 13 sacral GCTs [proximal extent of disease-S1 (10), S2 (2) and S3 (1)] were treated. Age ranged from 20 to 50 years. One patient had loss of bladder control at presentation. Treatment protocol included short term denosumab, angioembolisation and radiotherapy in different combinations. Patients were evaluated every 10-12 weeks. If disease ceased to progress no further treatment was advised. In case of progress, patient was advised additional denosumab and/or angioembolisation and/or radiotherapy till disease stopped progressing.

RESULTS

10 patients have non-progressive disease and are asymptomatic, 2 have non-progressive disease with occasional pain, 1 patient died. Follow-up duration (since final non-progression of disease) ranged from 15 to 54 months (mean 31 months). Total number of angio embolisation sessions ranged from 0 to 12 (mean = 4), total number of denosumab doses ranged from 5 to 16 (mean = 9). Five patients did not receive any radiotherapy, 5 received 50.4 Gy and one patient each received 50.4 + 30 + 12 Gy, 50.4 + 30 Gy and 50.4 + 12 Gy. The patient with loss of bladder control at presentation recovered. There were no other long-term complications.

CONCLUSION

This study offers a non-surgical management option that provides good mid-term local control while preserving neurological function in these complex lesions.

Extended curettage versus en bloc resection for the treatment of grade 3 giant cell tumour of the knee with pathologic fracture: a retrospective study

PURPOSE

For the treatment of giant cell tumour of the bone (GCTB) around the knee, preserving the native joint confers advantages over scarifying it. But, there is a controversy about the efficacy of intralesional curettage versus en bloc resection for treatment of such lesions. In this study, we compared local recurrence, functional outcomes, and complications of extended curettage and en bloc resection in these lesions.

METHODS

Patients with grade 3 GCTB of the distal femur or proximal tibia who were presented with a pathologic fracture and treated with either en bloc resection (n = 22) or extended curettage (n = 20) were included. The mean follow-up of the patients was 6.4 ± 1.9 years in the resection group and 5.5 ± 2.4 years in the extended curettage group. The primary outcome was a local recurrence. Secondary outcomes were limb function evaluated by the Musculoskeletal Tumor Society (MSTS) score and rate of complications.

RESULTS

Local recurrence was seen in four (20%) patients of the curettage group and three (13.7%) patients of the resection group (P = 0.69). The mean MSTS score was 24 ± 1.9 in the resection group and 26.5 ± 1.3 in the curettage group (P < 0.001). The number of complications was not significantly different between the two study groups (P = 0.49). However, the number of complications that required revision surgery was significantly more in the resection group (P = 0.049).

CONCLUSION

In grade 3 GCTB around the knee with pathologic fracture, extended curettage results in comparable oncologic outcomes to en bloc resection, while providing better function and a lower rate of revision.

Denosumab for Bone Giant Cell Tumor of the Distal Radius

There are conflicting reports regarding the outcome and effect of denosumab for distal radius giant cell tumor of bone (GCTB). The authors performed this study to evaluate the behavior of distal radius GCTB in relation to the type of treatment and the administration of denosumab. The files of 72 patients with distal radius GCTB treated from 1984 to 2018 were reviewed. Fourteen patients were administered denosumab. Surgical treatment consisted of curettage (25 patients) or resection (47 patients) and allograft or vascularized fibular head graft reconstruction. Median follow-up was 63.1 months (interquartile range [IQR], 35.5-107.1 months). The authors evaluated local recurrences, metastasis, function, and complications. The local recurrence rate was 30.6% at a median of 14.0 months (IQR, 10-19 months), with no difference between curettage and resection. The local recurrence rate was significantly higher in the patients who received denosumab. The metastasis rate was 9.7% at a median of 41.0 months (IQR, 15-114 months), with no difference regarding denosumab administration. Function was significantly better in patients after curettage. The complication rate was 25%; vascularized fibular graft reconstruction was associated with fewer complications. This study found that denosumab increases the risk of local recurrence after curettage, function is better after curettage, and vascularized fibular graft is the optimal reconstruction after resection of distal radius GCTB. [Orthopedics. 2020;43(5):284-291.].

Can Denosumab be used in combination with Doxorubicin in Osteosarcoma?

Osteosarcoma is an aggressive bone tumor of the pediatric age. It is therefore important to improve conventional therapies (chemotherapy and surgery). Anticancer drugs often cause osteoporosis due to a misbalance of RANK/RANK-L/OPG pathway.

Denosumab is a monoclonal antibody with high affinity and specificity to RANK-L, the ligand released by osteoblasts that enhances osteoclasts differentiation and bone resorption. It is used in osteoporosis and in other conditions characterized by bone mass loss. Doxorubicin is a chemotherapic drug used in several kinds of tumors, and also patients treated with it often develop osteoporosis.

We investigated the effects of Denosumab alone and in combination with Doxorubicin, in two human osteosarcoma cell lines (MG63 and U-2 OS). We evaluated the effect of these treatments on apoptosis, cell cycle progression, invasion capacity and bone metabolism.

We observed for the first time an anti-invasive effect of Denosumab in OS cells and confirmed its anti-osteoporotic activity also in Osteosarcoma. On the other hand, we demonstrate that Denosumab not only does not affect apoptosis and cell cycle progression, but when used in combination with Doxorubicin, it causes an unexpected reduction of its activity. These results indicate that the presence of Denosumab might inhibit the efficacy of the chemotherapic drug.

In conclusion, while our results certainly support and confirm the efficacy of Denosumab in Osteoporosis, we discourage the use of Denosumab in addition to conventional chemotherapy in Osteosarcoma, even though, certainly further investigations are necessary to better clarify the clinical role of this monoclonal antibody in cancer.

Denosumab-treated Giant Cell Tumors of Bone: A Clinicopathologic Analysis of 35 Cases From the French Group of Bone Pathology

Denosumab, an antibody directed against receptor activator of nuclear factor-κB ligand (RANKL), has recently been introduced in the treatment strategy of giant cell tumor of bone. In this study, we assessed the tumor changes induced by denosumab in a national multicentric series of 35 cases (French Bone Pathology Group network-ResOs). Tissue specimens collected before and after denosumab treatment were investigated for RANKL, H3.3 G34W, p63, and Ki-67 expression, and for H3F3A mutation. These parameters were put in correspondance with clinical and radiologic presentation to identify prognostic factors, and more specifically, predictive markers of an optimal histologic response to denosumab, identified as a ≥50% loss in giant cells with fibrosis and ossification. The main changes in posttreatment specimens showed an induction of ossification (P=2.10), an increased fibrosis (P=3.10), and a major decrease in giant cells (P=6.10). No significant change in mononuclear tumor cell density and in patterns of expression of RANKL (P=0.061) and H3.3 G34W was observed (P=0.061). An optimal histologic response to denosumab treatment was associated with an enhanced progression-free survival (P=0.010 in univariate analyses; P=0.040 in multivariate analyses). The initial number of giant cells was predictive of the histologic response to treatment (P=0.016). In summary, denosumab treatment induced radical changes in the tumor. The histologic response, despite the absence of objective regression of the mononuclear cells, was associated with an enhanced progression-free survival. Greater numbers of giant cells represented the only predictive indication of an optimal histologic response to denosumab treatment.

Prognostic role of PD-L1 and immune-related gene expression profiles in giant cell tumors of bone

Giant cell tumor of bone (GCTB) is a locally aggressive and rarely metastatic tumor, with a relatively unpredictable clinical course. A retrospective series of 46 GCTB and a control group of 24 aneurysmal bone cysts (ABC) were selected with the aim of investigating the PD-L1 expression levels and immune-related gene expression profile, in correlation with clinicopathological features. PD-L1 and Ki67 were immunohistochemically tested in each case. Furthermore, comprehensive molecular analyses were carried out using NanoString technology and nCounter PanCancer Immune Profiling Panel, and the gene expression results were correlated with clinicopathological characteristics. PD-L1 expression was observed in 13/46 (28.3%) GCTB (and in 1/24, 4.2%, control ABC, only) and associated with a shorter disease free interval according to univariate analysis. Moreover, in PD-L1-positive lesions, three genes (CD27, CD6 and IL10) were significantly upregulated (p < 0.01), while two were downregulated (LCK and TLR8, showing borderline significance, p = 0.06). Interestingly, these genes can be related to maturation and immune tolerance of bone tissue microenvironment, suggesting a more immature/anergic phenotype of giant cell tumors. Our findings suggest that PD-L1 immunoreactivity may help to select GCTB patients with a higher risk of recurrence who could potentially benefit from immune checkpoint blockade.

Benign albeit glycolytic: MCT4 expression and lactate release in giant cell tumour of bone

Giant cell tumour of bone (GCTB) is a histologically benign, locally aggressive skeletal lesion with an unpredictable propensity to relapse after surgery and a rare metastatic potential. The microscopic picture of GCTB shows different cell types, including multinucleated giant cells, mononuclear cells of the macrophage-monocyte lineage, and spindle cells. The histogenesis of GCTB is still debated, and morphologic, radiographic or molecular features are not predictive of the clinical course. Characterization of the unexplored cell metabolism of GCTB offers significant clues for the understanding of this elusive pathologic entity. In this study we aimed to characterize GCTB energetic metabolism, with a particular focus on lactate release and the expression of monocarboxylate transporters, to lie down a novel path for understanding the pathophysiology of this tumour. We measured the expression of glycolytic markers (GAPDH, PKM2, MCT4, GLUT1, HK1, LDHA, lactate release) in 25 tissue samples of GCTB by immunostaining and by mRNA and ELISA analyses. We also evaluated MCT1 and MCT4 expression and oxidative markers (JC1 staining and Bec index) in tumour-derived spindle cell cultures and CD14+ monocytic cells. Finally, we quantified the intratumoural and circulating levels of lactate in a series of 17 subjects with GCTB. In sharp contrast to the benign histological features of GCTB, we found a high expression of glycolytic markers, with particular reference to MCT4. Unexpectedly, this was mainly confined to the giant cell, not proliferating cell component. Accordingly, GCTB patients showed higher levels of blood lactate as compared to healthy subjects. In conclusion, taken together, our data indicate that GCTB is characterized by a highly glycolytic metabolism of its giant cell component, opening new perspectives on the pathogenesis, the natural history, and the treatment of this lesion.

Denosumab in giant cell tumour of bone in the pelvis and sacrum: Long-term therapy or bone resection?

INTRODUCTION

Surgery of GCTB in sacrum and pelvis is challenging, with high rates of complications and local recurrence. Denosumab can consolidate the peripheral rim of the tumour, thus reducing the rate of morbidities of surgery. The aim of this paper is to evaluate the use of denosumab in pelvic/sacrum giant cell tumours of bone (GCTB).

PATIENTS AND METHODS

We retrospectively reviewed a cohort of 26 patients with aggressive GCTB in sacrum or pelvis treated with denosumab at two referral centres. Clinical response and local recurrence were recorded and the radiologic responses were evaluated with the MDA criteria.

RESULTS

69% of the pelvic GCTB treated with denosumab presented partial or good radiologic responses (type 2A or 2B) after 49 weeks of treatment. Denosumab was administered as adjuvant therapy prior and after surgery in 11 patients (group A), and as the only treatment in 15 patients (group B). In group A, 62% of local recurrence was observed in patients treated with intralesional curettage. No recurrences were identified after en bloc resection. In group B, 9 patients were on continuous bimonthly long term denosumab administration with type 2A and 2B responses. Six patients stopped denosumab and 66% remained stable after 10 months of follow-up.

CONCLUSIONS

Long-term denosumab therapy can be considered with curative intent for pelvic and sacrum GCTB. If surgical intervention is required wide resection may be advisable to reduce the risk of recurrence.

Short-term Preoperative Denosumab With Surgery in Unresectable or Recurrent Giant Cell Tumor of Bone

Objective

The purpose of this retrospective study was to evaluate the clinical and oncological results of combination treatment of short‐term preoperative denosumab (the receptor activator of nuclear factor kappa‐B ligand inhibitor) with surgery in unresectable or recurrent cases of giant cell tumor of the bone (GCTB).

Methods

Between 2016 and 2018, 11 eligible patients (1 man, 10 women, mean age 38.1 years) with grade 3 GCTB were treated with a combination of short‐term (six doses) preoperative denosumab and surgery in a single institution. The clinical, radiological, and pathological alteration after the denosumab treatment were compared. The oncological results of the combination therapy were also recorded. Meanwhile, adverse effects or complications of denosumab, if any, were reported.

Results

The median follow‐up time after surgical procedure was 30 months (range 13–45 months). After 3–4 denosumab injections, pain relief was observed in all patients. In two spine patients, the neurological status improved after four doses of treatment. Intraoperatively, the margin of the tumor became clear and the intensity of the tumor increased while the blood supply around and within the lesion decreased. Within the lesion, the typically soft and loose tissue were replaced by the tough and dense fibro‐osseous tissue. The mean diameter of the lesion before and after treatment was 61.55 ± 22.49 mm and 51.81 ± 21.12 mm, respectively, and the T‐score was 1.02 (P = 0.32). Variable calcification was observed at the periphery and within the lesion. A total of three patients experienced local recurrence in this study. In the resection group, only one extremity patient had soft tissue recurrence that was treated with en‐bloc excision. In the curettage group, two of three sacral tumor patients had local occurrence. Both refused re‐operation and restarted the monthly denosumab injection thereafter, and the lesions remained stable at the final follow up. Finally, no adverse effects or complications related to denosumab treatment were found.

Conclusion

For the unresectable or recurrent GCTB cases, short‐term (six doses) preoperative use of denosumab improved clinical symptoms, decreased the tumor size, and increased the tumor density. The changes in tumors, in turn, simplified the tumor removal manipulation and, subsequently, decreased the local recurrence for the resection surgery. For the curettage, the denosumab‐induced changes had mixed impacts, and shorter term (fewer than six doses) usage may be more appropriate. Our six‐dose regime was deemed safe, while the safety of long‐term use remains unknown.

Curettage as first surgery for bone giant cell tumor : adequate surgery is more important than oncology training or surgical management by high volume specialized teams

We reviewed the files of 203 patients with extremities GCTB treated with curettage as first surgery from 1990 to 2013. Median follow-up was 84.2 months. We evaluated whether the years of practice and training in orthopaedic oncology are associated with local recurrences, function and complications after curettage as first surgery for giant cell tumour of bone (GCTB). Local recurrences were not significantly different between orthopaedic oncology trained and non-trained orthopaedic surgeons and between orthopaedic surgeons with < 10 years and ≥ 10 years of practice. Function was not significantly different between orthopaedic oncology trained and non-trained surgeons and between orthopaedic surgeons with < 10 years and ≥ 10 years of practice. The only important univariate and multivariate predictor for local recurrence was PMMA adjuvant. Complications were not significantly different between orthopaedic oncology trained and non-trained orthopaedic surgeons and between orthopaedic surgeons with < 10 years and ≥ 10 years of practice. Curettage may be effectively performed as first surgery for GCTB by early-career (< 10 years of practice) non-trained orthopaedic oncology orthopaedic surgeons. PMMA adjuvant is recommended after appropriate curettage.

Successful total en bloc spondylectomy of the L3 vertebra with a paravertebral giant cell tumor following preoperative treatment with denosumab: a case report

BACKGROUND

Giant cell tumor is known to be a benign neoplasm that arises most commonly in the long bones, while cases in the spine are rare. Recently, denosumab, a monoclonal antibody that inhibits receptor activator of nuclear factor-kappa β ligand, has been used to treat patients with giant cell tumor. However, there are few reports of total en bloc spondylectomy being used for paravertebral giant cell tumor lesions following denosumab therapy.

CASE PRESENTATION

Our patient was a 20-year-old Japanese woman with a 4-month history of lower back pain. A spinal computed tomography scan and magnetic resonance imaging of her lumbar spine revealed an osteolytic lesion involving the L3 vertebral body, and the tumor extended toward the left side of the paravertebral soft tissue and into the left pedicle. The lesion was diagnosed as a giant cell tumor by needle biopsy. Denosumab treatment calcified the paravertebral giant cell tumor lesion and the tumor vertebral body was removed completely by total en bloc spondylectomy.

CONCLUSION

This case report describes a patient with a paravertebral giant cell tumor who was successfully treated by preoperative denosumab injection followed by total en bloc spondylectomy.

Retrospective analysis of 51 intralesionally treated cases with progressed giant cell tumor of the bone: local adjuvant use of hydrogen peroxide reduces the risk for tumor recurrence

BACKGROUND

Giant cell tumor of the bone (GCT) has high local recurrence rates and the prognosis is hard to predict. We therefore retrospectively analyzed clinical outcome and recurrences of 51 GCT cases focusing on the effects of adjuvant local use of hydrogen peroxide.

METHODS

The series enclosed 51 advanced GCT cases of the upper and lower extremities (n = 27 Campanacci grade III; n = 24 grade II; n = 39 surgery at our institution, n = 12 elsewhere). Mean follow-up was 88.3 (± 62.0) months. Surgical details, histology, metastases, recurrences, and interview-based data on satisfaction and function including the Musculoskeletal Tumor Society (MSTS) score were evaluated. It was investigated whether hydrogen peroxide was additionally used or not to clean the tumor cavity after curettage as we hypothesized influence on recurrences. To analyze the underlying mechanisms, GCT-derived stromal cell lines were cultured in vitro and tested for cell viability and apoptosis after treatment with hydrogen peroxide. Statistical analysis was performed with Student's t tests, analysis of variance (ANOVA) with post hoc testing, Mann-Whitney U tests, chi-square tests, Kaplan-Meier analysis, and multivariate Cox regression analysis.

RESULTS

The whole series had 21 recurrences (41%). Eleven recurrences were found (28%) after surgery at our institution. Kaplan-Meier analysis of cumulative recurrence-free survival revealed at 2 years follow-up 69% (72%, only our institution) and at 10 years follow-up 54% (68%, only our institution). Intralesional resection was performed by vigorous curettage, burring, and defect filling with either polymethylmethacrylate bone cement (n = 45) or cancellous bone from the iliac crest (n = 6). Univariate chi-square analysis showed significantly lower recurrence rate after bone cement filling (2.3-fold, p = 0.024). Cleaning of the lesion cavity with hydrogen peroxide significantly reduced recurrence rate (whole collective 2.9-fold, p = 0.004; our institution 2.8-fold, p = 0.04) and significantly increased cumulative recurrence-free survival rate (whole collective at 10 years follow-up 74% versus 31%, p = 0.002; our institution 79% versus 48%, p = 0.02) compared to cases without hydrogen peroxide treatment. In multivariate analysis, significant risk factors for recurrence were pathological fracture (hazard ratio 3.7; p = 0.04), high mitosis rate (hazard ratio 15.6; p = 0.01), and lack of hydrogen peroxide use (hazard ratio 6.0; p = 0.02). In vitro cell culture analyses found apoptotic nature of hydrogen peroxide induced GCT cell death.

CONCLUSIONS

The present series proved for the first time that additional cleaning of the tumor cavity with hydrogen peroxide before defect filling significantly reduced recurrence rate and significantly increased recurrence-free survival in advanced but intralesionally treated GCT cases.

How to optimize the therapeutic effect of free autogenous fibula graft and wrist arthroplasty for giant cell tumors of distal radius?

Objective

The purpose of this study is to retrospectively analyze the clinical efficacy of free fibula autograft and wrist arthroplasty in the treatment of giant cell tumors (GCT) of distal radius.

Methods

We retrospectively reviewed 26 patients with GCT of distal radius who underwent free autogenous fibula graft and wrist arthroplasty for repairing residual defect after en-block resection. The length of the fibula graft was 8.2 cm (6–10 cm). Postoperative follow-up regularly for an mean of 66.9 months. Bone healing was assessed by radiographs, pain was assessed by Visual Analog Scale (VAS) score and limb function was evaluated by Musculoskeletal Tumor Society (MSTS) score and disabilites of the arm, shoulder and hand (DASH) score. The range of motion (ROM) of wrist and grip strength were also evaluated.

Result

There were four males and 22 females with an mean age of 36.7 years (19–60 years); the mean length of lesions was 4.8 cm (2.3–6.6 cm); 21 primary cases and five recurrent cases; eight cases of Campanacci Grade II, 18 cases of Grade III. We had no postoperative lung metastasis and only one case had a local recurrence, three cases (11%) with subluxation of lower ulnoradial joints and five cases (19%) showed narrowing of wrist joint space. The mean postoperative VAS pain score was 0.7 ± 0.7 and grip strength retained 71% of the normal hand, MSTS score was 27.7 ± 1.1 and DASH score was 9.0 ± 3.7. The ROM of the involved wrist only slightly restricted and no donor complications. Postoperative wrist joint function was significantly improved.

Conclusion

Strict surgical resection boundary and solid reconstruction of wrist joint capsule are the key to achieving excellent oncological prognosis and function of distal radius GCT.

Neoadjuvant denosumab: its role and results in operable cases of giant cell tumour of bone

AIMS

The aims of this study were to evaluate the efficacy of preoperative denosumab in achieving prospectively decided intention of therapy in operable giant cell tumour of bone (GCTB) patients, and to document local recurrence-free survival (LRFS).

PATIENTS AND METHODS

A total of 44 patients received preoperative denosumab: 22 to facilitate curettage, 16 to facilitate resection, and six with intent of converting resection to curettage. There were 26 male and 18 female patients. The mean age was 27 years (13 to 47).

RESULTS

The mean number of denosumab treatments was five (2 to 7) per patient. In 42 of 44 patients (95%), denosumab helped to achieve prospectively decided intention. A total of 41 patients were available for follow-up at a mean follow-up of 34 months (24 to 48). There were 12 local recurrences (29%), in 11 patients (11/25, 44%) who had curettage and in one patient (1/16, 6%) who had resection. The mean time to local recurrence was 16 months (8 to 25). The LRFS was 76% at two years: 94% for cases with resection and 64% for cases with curettage (p = 0.013).

CONCLUSION

Although local control rates are unlikely to improve with use of preoperative denosumab, a short preoperative course of denosumab can facilitate surgery in certain cases of operable GCTB, with a high risk of local recurrence making curettage or resection technically easier. It may also help in converting a lesion requiring resection to a lesion that could possibly be treated with curettage.

Present day controversies and consensus in curettage for giant cell tumor of bone

BACKGROUND

The ideal treatment for giant cell tumor of bone (GCTB) is still controversial. The purpose of this study was to evaluate whether curettage was successful in the treatment of GCTB. Intralesional curettage with adjuvant therapies, such as high-speed burring, polymethylmethacrylate, phenol, ethanol, and liquid nitrogen, may be used to reduce the local recurrence rate. However, there is no consensus on the optimal use of curettage, along with fillers and adjuvants, to limit the recurrence rate.

METHODS

We performed a systematic review of articles using the terms long bones, GCTB, and treatment. Case reports, reviews, opinion articles, or technique notes were excluded based on the abstract. Twenty-six articles included in this review were then studied to establish the index in suggesting the surgical treatment of GCTB.

RESULTS

The patient's gender, their age, the Campanacci grade of their tumor, and the type of surgery they had were not significantly associated with the local recurrence rate. Local recurrences seemed to be associated with the site of the tumor, occurring more frequently in the proximal femur or distal radius. A pathological fracture was not a contraindication for intralesional curettage. Treatment with denosumab did not decrease the local recurrence rate in patients who had been treated with curettage.

CONCLUSION

The current literature seems to suggest that the ideal treatment for GCTB is to remove the tumor while preserving as much of the joint as possible. Local recurrent tumors can be treated with curettage to keep the re-recurrence rate within an acceptable limit. The choice for how to treat GCTB in the proximal femur or distal radius requires special attention.

Denosumab does not decrease the risk of lung metastases from bone giant cell tumour

PURPOSE

There are conflicting reports on the effect of denosumab on lung metastases in patients with giant cell tumor (GCT) of bone. To address these reports, we performed this study to determine if denosumab prevents lung metastasis and to evaluate univariate and multivariate predictors for lung metastases in these patients.

MATERIALS AND METHODS

We retrospectively studied 381 GCT patients with surgery alone and 30 GCT patients with surgery and denosumab administration. The median follow-up was 85.2 months (IQR, 54.2-124.4 months). We evaluated lung metastases and local recurrences, univariate and multivariate predictors for lung metastases, response, and adverse events of denosumab administration.

RESULTS

The occurrence of lung metastases was similar (surgery alone 4.7%, 18 patients; denosumab administration 3.3%, 1 patient); however, the occurrence of local recurrences was significantly higher in the patients with denosumab administration. Denosumab administration was not an important predictor for lung metastases; Campanacci stage and type of surgery were the only univariate predictors for lung metastases, and type of surgery and local recurrence were the only multivariate predictors for lung metastases. Histology showed viable tumour in all tumor specimens of the patients with denosumab administration.

CONCLUSION

Denosumab does not decrease the risk of lung metastases in patients with bone GCT; the only important predictors for lung metastases in these patients are type of surgery and local recurrence. However, because the number of patients with lung metastases was small for a multivariate analysis, the possibility of denosumab's effect could not be completely eliminated.

Giant cell tumor of a rib following denosumab treatment

Giant cell tumor (GCT) of the bone is an aggressive lytic lesion, commonly treated with surgery. Denosumab is a relatively recently introduced osteoclast activation inhibitor used for neoadjuvant therapy of GCT. Here we report the case of a GCT of a rib undergoing extensive osteosclerosis on computed tomography imaging following treatment with denosumab.

Giant cell tumours of bone treated with denosumab: histological, immunohistochemical and H3F3A mutation analyses

AIMS

Denosumab, a human monoclonal antibody directed against the receptor activator of nuclear factor-κB ligand (RANKL), is a therapeutic agent for giant cell tumour of bone (GCTB). Although some studies have reported that denosumab shrinks tumours and induces bone formation, the actual effects of RANKL suppression on GCTB remain unclear. A mutation in the H3 histone family member 3A gene (H3F3A) was recently identified as a genetic signature for GCTB. The aim of this study was to investigate the histopathological features and H3F3A mutation status of GCTBs treated with denosumab.

METHODS AND RESULTS

Nine biopsy-diagnosed patients with GCTB, who underwent curettage after neoadjuvant denosumab therapy, were reviewed. Immunohistochemistry for NFATc1 (an osteoclast marker), RUNX2 (an osteoblast marker) and histone H3.3 G34W (G34W, a GCTB marker) was performed; furthermore, H3F3A mutation status was examined with direct sequencing. Before therapy, GCTBs comprised NFATc1+ and RUNX2+ cells. All cases were G34W+ and contained H3F3A mutations. After therapy, the osteoclast-like giant cells disappeared. Areas of slender spindle cell proliferation and reticular woven bone that were NFATc1- and RUNX2+ replaced the lesions in various proportions. However, all post-therapy lesions still contained many G34W+ cells and harboured H3F3A mutations. Immunofluorescence double staining revealed that RUNX2+ mononuclear cells coexpressed G34W in pre-therapy and post-therapy lesions. Two patients experienced radiologically detected local recurrence within 2 years.

CONCLUSIONS

Denosumab therapy effectively decreases the number of osteoclastic cells in GCTBs. However, the neoplastic cells with H3F3A mutation survive denosumab treatment and undergo dramatic histological changes in response to this agent.

Nomograms for prognostic factors of spinal giant cell tumor combining traditional clinical characteristics with inflammatory biomarkers after gross total resection

Giant cell tumor (GCT) of bone is a common primary bone tumor, which exhibits local aggressiveness and recurrent potential, especially for the spinal lesion. Increasing evidence indicates that inflammation plays a vital role in tumorigenesis and progression. The prognostic value of inflammatory biomarkers in GCT has not been established. A retrospective analysis was conducted in patients with spinal GCT in Changzheng Hospital Orthopedic Oncological Center (CHOOC) between January 2005 and October 2015 and 129 patients were identified eligible. Traditional clinical parameters and inflammatory indexes such as Neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), lymphocyte-to-monocyte ratio (LMR), and albumin/globulin ratio (AGR) were concluded and analyzed. Kaplan-Meier analysis was used to calculate the disease-free survival (DFS). Cox regression analysis was performed to assess the prognostic factors. Nomograms were established to predict DFS quantitatively for the first time, and Harrell’s concordance index (c-index) was adopted to evaluate prediction accuracy. As results, the DFS was 78.3% in the cohort. Patients were stratified into 2 groups by NLR (≤ 2.70 and > 2.70), PLR (≤ 215.80 and > 215.80), LMR (≤ 2.80 and >2.80) and AGR (< 1.50 and ≥ 1.50). Patients with NLR > 2.70, PLR > 215.80, LMR ≤ 2.80 and AGR < 1.50 were significantly associated with decreased DFS (p < 0.05). Multivariate analysis indicated that treatment history, tumor length, bisphosphonate treatment, NLR and PLR were independent factors of DFS (p < 0.05, respectively). In addition, nomogram on DFS was established according to all significant factors, and c-index was 0.728 (95% CI: 0.710-0.743). Nomograms based on DFS can be recommended as practical models to evaluate prognosis for spinal GCT patients.