Giant cell tumour of bone: morphological, biological and histogenetical aspects

Distal Ulna Giant Cell Tumor treated by Resection without Reconstruction: What were the functional outcomes and review of literature

Introduction

Giant Cell Tumours (GCT) are benign tumours with aggressive potential that disrupt the local bony architecture, which can be especially problematic in peri-articular locations. Our aim was to assess the outcomes of patients with GCT of the distal ulna who were treated by resection without reconstruction.

Methods

The study included 21 patients with distal ulna GCT that were treated with resection without reconstruction. There were 12 males and 9 females, with a mean age of 30.4years (range 14-45 years). The patients mean follow-up period was 4.4 years, with a two-year minimum follow-up.

Results

Painful swelling was the presenting symtom in all cases. Nineteen patients had Campanacci grade 3 and two had Campanacci grade 2. The mean resected length of the distal ulna was 6.8 cm (range 4-10) cm. The Musculoskeletal Tumor Society score (MSTS) was 26.1. (range 22-28). Grip strength of the affected hand was reduced by 10.5% on average. (range 0%-16%). Two patients were having multi-centric disease on presentation and none of the cases had pathological fracture on presentation. One case had a local recurrence which was treated with surgery.

Conclusion

Based on current study, GCT of the distal ulna, en bloc resection without reconstruction can be recommended as a valuable treatment option for Campanacci grades 2 and 3 tumours. Resection of the distal end of the ulna without reconstruction results in excellent functional outcomes, with forearm rotational movement and hand function preserved. According to review of literature this is the largest series of GCT Ulna and we recommend a multicentre and comparitive studies on this topic.

Giant Cell Tumor of Bone, Rare Inferior Orbit Location

Giant cell tumor of bone (GCTB) typically presents in the epiphysis of long bones and occurs in the skull in less than 1% of cases. When GCTB is diagnosed in the skull, it is primarily seen in the temporal and sphenoid bones. GCTB is an osteoclastic stromal tumor that is locally aggressive and tends to recur. We present a case of a 43-year-old woman with slowly progressive, left-sided proptosis, eyelid swelling, photophobia, epiphora, and pressure sensation. Computed tomography and magnetic resonance imaging revealed an enhancing tumor in the left inferior orbit with infiltration into the maxillary sinus roof. Histological examination was conclusive for a giant cell tumor of the maxillary bone presenting as an inferior orbital mass. Gross total surgical resection was performed via an inferior anterior orbitotomy, and the patient had resolution of symptoms without recurrence in her postoperative course to date. This report contributes to the scarce literature available on this type of tumor of skull bones, specifically presenting the first case in the maxillary bone of the floor of the orbit.

Human Chorionic Gonadotropin Regulates the Smad Signaling Pathway by Antagonizing TGF-β in Giant Cell Tumor of Bone

BACKGROUND

Giant cell tumor of bone (GCTB) is a locally aggressive bone tumour aggravated by stromal cell proliferation and metastasis.

OBJECTIVE

We investigated the mechanism of action of human chorionic gonadotropin (HCG) in mediating GCTB proliferation and invasion.

METHODS

The expression of HCG was quantified using quantitative real-time PCR. After the primary stromal cells were isolated and identified, the function of HCG in GCTB was estimated using the cell counting kit-8, flow cytometry, scratch experiment, transwell assay, Western blot, and immunofluorescence. Moreover, the mechanism of HCG was assessed through western blotting.

RESULTS

HCG expression was decreased in clinical tissue samples from patients with GCTB. We validated that HCG repressed stromal cell proliferation, migration, invasion, autophagy, and epithelial- mesenchymal transition (EMT) and promoted cell apoptosis in GCTB. We also verified that HCG repressed the autophagy and EMT of stromal cells through the Smad signaling axis in GCTB. HCG inhibited the transduction of the Smad signaling pathway by restraining the binding of the TGF-β II receptor to ligand Activin A.

CONCLUSION

HCG restrained the Smad signaling pathway by antagonizing TGF-β signaling in GCTB. HCG may serve as a useful patent to treat GCTB.

Reconstruction After En Bloc Resection of a Distal Radius Tumor. An Updated and Concise Review

The distal radius is rarely affected by either primary or metastatic bone cancers. The most frequent tumors of the distal radius are giant cell tumors, which are benign tumors with the propensity to invade. En bloc excision of giant cell tumors of the distal radius achieves a low recurrence rate but compromises the wrist joint, necessitates a significant reconstruction, and has functional consequences. Reconstruction after en bloc resection of a distal radius bone tumor is challenging. Furthermore, orthopedic oncologists disagree on treating such long bone anomalies most effectively. The present article summarizes the various biological and non-biological reconstruction techniques performed after en bloc resection of a distal radius tumor, discusses the advantages and disadvantages of each reconstruction strategy, and summarizes several case studies and case reports.

A Rare Case of Giant Cell Tumour of the Medial Epicondyle of the Humerus Managed With Curettage and Bone Grafting

Giant cell tumours (GCTs) of the medial epicondyle of the humerus are rare. These are generally benign tumours but have the potential to be locally aggressive. They can invade the adjacent joint or the surrounding soft tissues or, in rare cases, cause distant metastasis. Locally aggressive GCTs are generally treated with wide resection, curettage, and bone grafting, followed by joint reconstructions. Here we present a case of a 49-year-old female with a history of swelling over the medial epicondyle of the humerus for six months. The patient was diagnosed with a locally aggressive GCT and was managed with wide excision of the tumour followed by sandwich bone grafting. A two-year follow-up of the patient shows no signs of recurrence. The patient is pain-free and has decent elbow function.

Giant Cell Tumor of Thumb Proximal Phalanx-A Case Report

Introduction

The prevalence of giant cell tumor (GCT) of bone is approximately 5% of all primary osseous tumors. It accounts for <2% of the total cases as far as the involvement of the hand is concerned. Numerous studies stated that <1% of cases have phalangeal involvement of the thumb.

Case Report

This case is delineated for its unusual location (thumb proximal phalanx) in a 42-year-old male patient managed by single-stage en-bloc excision, arthrodesis, and web-space deepening procedure without donor-site morbidity. It is known for its notorious nature for reoccurrence (10-50%) and transformation into malignancy (10%); therefore, meticulous dissection is a prerequisite.

Conclusion

GCT of the thumb proximal phalanx is quite an unusual presentation. Although very rare, it is thought to be one of the most aggressive varieties of benign bone tumor observed to date. Amid a high rate of recurrence, careful preoperative planning is pivotal for fruitful outcome both anatomically and functionally.

Aggressive giant cell lesion of mandible-confusing to common: true neoplasm versus reactive lesion

Destructive lesions in the craniofacial region especially in the jawbones, if associated with giant cells, include a spectrum of lesions that pose difficulty in diagnosis. The nature of such a lesion in the jawbones is questionable about whether it is a reactive/benign lesion or aggressive/non-aggressive. Clinical, radiological and histopathological correlation may be a reliable indicator to differentiate between the qualities of the lesion, which directly accounts for effective and individual planning of the treatment. Here we present a case of a woman in her late 20s with an unusual destructive lesion of the mandible.

Giant cell tumor of sacral vertebra in an adolescent without neurodeficit: A case report and review of the literature

Background:

Giant cell tumors (GCTs) are locally aggressive benign primary bone tumors that rarely occur in the spine. Their treatment methods include denosumab, bisphosphonates, and/or different surgical techniques. Here, we present the successful treatment of a sacral GCT in a 13 years old.

Case Description:

A 13-year-old male presented with back pain and paraparesis of 3-week duration. Radiological studies demonstrated an S1 lytic lesion. He underwent an excisional biopsy and anterior and posterior resection combined with a lumbopelvic fusion. One year later, there has been no tumor recurrence.

Conclusion:

We successfully treated an S1 sacral GCT in a 13-year-old male utilizing a wide anteriorand posterior excision combined with a lumbopelvic fusion.

Management of a rare giant cell tumor of the distal fibula: A case report

BACKGROUND

Aggressive giant cell tumor of the distal fibula is so rare that no consensus on a surgical strategy has been reached. Thus, an appropriate treatment strategy is still important to discuss.

CASE SUMMARY

A 61-year-old man who had been experiencing progressive swelling of the left lateral malleolus accompanied by pain for half a year was presented at our hospital. He had never been treated prior to coming to our hospital. Preoperative imaging revealed a 10 cm × 6 cm mass located in the body of the distal fibula. Pathological biopsies confirmed it was a giant cell tumor. Preoperative examination revealed he had dilated cardiomyopathy with class 3 cardiac function. The cardiologist and anesthesiologist determined that he could tolerate the operation, but the operation should be as short and minimally invasive as possible. With the patient’s consent, we performed a tibiotalar fusion and followed up with him for 2 years, finding no recurrence and a satisfactory recovery.

CONCLUSION

Tibial talus fusion is an effective method for the treatment of distal fibula tumors.

Malignant Brain and Spinal Tumors Originating from Bone or Cartilage

Malignant bone tumors affecting the brain and spine are a rare and exceedingly difficult-to-treat group of diseases. Most commonly consisting of chordoma and chondrosarcoma, these tumors also include giant-cell tumors and osteosarcomas. This chapter will cover the background, epidemiology, genetics, molecular biology, histopathology, radiographic features, clinical manifestations, therapeutic approaches, and clinical management of each entity.

Comparison of the prognostic factors of total en bloc spondylectomy and total piecemeal spondylectomy in patients with Enneking stage III giant cell tumor in the thoracic and lumbar spine

PURPOSE

To compare total en bloc spondylectomy with marginal margins against piecemeal spondylectomy with intralesional margins in the surgical treatment of Enneking stage III spinal giant cell tumor (GCT) in terms of local recurrence.

METHODS

A retrospective survival analysis of patients with Enneking stage III GCT who underwent TES with marginal margins or total piecemeal spondylectomy with intralesional margins was performed between January 2006 and April 2020. Local recurrence-free survival (LRFS) was the time between the date of surgery and recurrence. Factors with p-values < 0.05 in the univariate analysis were included in the multivariate analysis using proportional hazard analysis.

RESULTS

Sixty patients (25 men and 35 women) with a mean age of 35.6 (range 11-71) years were included. The mean follow-up duration was 93 (range 24-198) months. Two patients were lost to follow-up 6 and 14 years after the procedure. Over a 10-year period, the recurrence rate was 13.3%. The 2-, 5-, and 10-year LRFS rates were 95%, 88%, and 78%, respectively. Univariate analysis identified total piecemeal spondylectomy and no adjuvant radiotherapy as prognostic factors for LRFS. Multivariate Cox-regression models showed a significant association between local recurrence and total piecemeal spondylectomy and no adjuvant radiotherapy.

CONCLUSION

TES with marginal margins is better than total piecemeal spondylectomy with intralesional margins owing to its lower postoperative recurrence rate. Adjuvant radiotherapy should be administered to reduce postoperative recurrence rates.

Giant Cell Tumor of the Proximal Fibula With Common Peroneal Nerve Neuropraxia

Giant cell tumor (GCT) is among the commonest benign tumors and represents 5% of bone neoplasms. It is more common in young adults aged between 20 and 40 years. The distal femur is one of the most common sites, with the proximal tibia and distal radius the next frequently involved site, respectively. Previous research indicates that the tumor is an uncommon occurrence at this given age and location. Surgical management is the primary treatment for GCT universally. Extended curettage with the use of an argon beam cauterizer, a power burr, bone cement, hydrogen peroxide, phenol, liquid nitrogen, and zinc chloride are some of the treatment modalities for GCT. Opting for appropriate surgical treatments plays a crucial role to reduce the rate of recurrence and improve functional and oncological outcomes. In this case study, a 55-year-old male was diagnosed with GCT of the head of the right fibula with foot drop. The patient was managed with wide excision of the tumor and anchoring of lateral collateral ligament and biceps femoris to medial tibia condyle followed by postoperative galvanic stimulation for common peroneal nerve neuropraxia and guarded weight-bearing mobilization with bracing for knee joint. After 12 months of follow-up, there is no evidence of recurrence with a stable knee joint and dorsiflexion of the right ankle up to the neutral position.

A Tertiary Care Centre Experience of Recurrent Giant Cell Tumor Around the Knee Joint

Introduction: Giant cell tumor (GCT) is a benign but locally aggressive bone tumor. It has a peak incidence between 30-40 years with a predilection for the epiphyseal/metaphyseal region of bone. The most common locations for bone GCT are the distal femur, proximal tibia, distal radius, and sacrum in decreasing order.

Material and Methods: In this retrospective study, 22 patients (13 females and nine males) with recurrent giant cell tumors around the knee joint between 2009-2022, with a mean age of 30.2 years (range: 18-55) were included. The patients were followed up monthly for three months, three-monthly for the next two years, six-monthly for the next five years, and thereafter, yearly. The mean follow-up period was 36.97 months (range 23-120 months).

Results: There were 19 recurrences after curettages and three after resections. Re-extended curettage was done in 17 cases and the resultant cavities were filled with autologous bone grafts in six and with polymethyl methacrylate (PMMA) cement in the other 11 cases. Reconstruction with megaprosthesis was done in two patients whereas knee arthrodesis was done in two patients after wide resection. The average Musculoskeletal Tumor Society (MSTS) score of our series of 22 patients was 23.1 (Range: 19-30).

Conclusion: Campanacci grade 1 and 2 lesions can be successfully treated with extended curettage and bone grafting/bone cementing. For patients with grade 3 lesions, there are two options available according to the financial status of the patient; the first option is reconstruction with prosthesis and the other option is arthrodesis.

Recurrence of GCTB of Wrist in an Autografted Non-vascularized Fibula: A Case Report

Introduction

Distal radius is known to have high percentage of recurrences in giant cell tumor (GCT) despite best efforts. We would like to present a case where the recurrence unusually occurred in the graft and the complications associated with it.

Case Report

A 45-year-old woman, who had previously undergone curettage of GCT distal radius, presented with recurrence of lesion which was managed initially with resection and non-vascularized fibular autograft reconstruction. Tumor again recurred in the autografted fibula which was managed by curettage and cementing. Due to progressive collapse of the carpus, resection of the autograft and wrist arthrodesis was carried out.

Conclusion

Recurrence of GCT is a challenging problem. Wide resections may not always avoid recurrences. Patients should be made aware of the extend of recurrence that can happen in spite of the best efforts.

Update on the pathogenesis and genetics of Paget’s disease of bone

Studies over the past two decades have led to major advances in the pathogenesis of Paget’s disease of bone (PDB) and particularly on the role of genetic factors. Germline mutations of different genes have been identified, as a possible cause of this disorder, and most of the underlying pathways are implicated in the regulation of osteoclast differentiation and function, whereas other are involved in cell autophagy mechanisms. In particular, about 30 different germline mutations of the Sequestosome 1 gene (SQSTM1) have been described in a significant proportion of familial and sporadic PDB cases. The majority of SQSTM1 mutations affect the ubiquitin-binding domain of the protein and are associated to a more severe clinical expression of the disease. Also, germline mutations in the ZNF687 and PFN1 genes have been associated to severe, early onset, polyostotic PDB with increased susceptibly to neoplastic degeneration, particularly giant cell tumor. Mutations in the VCP (Valosin Containing Protein) gene cause the autosomal dominant syndrome “Inclusion Body Myopathy, PDB, Fronto-temporal Dementia,” characterized by pagetic manifestations, associated with myopathy, amyotrophic lateral sclerosis and fronto-temporal dementia. Moreover, germline mutations in the TNFRSF11A gene, which encodes for RANK, were associated with rare syndromes showing some histopathological, radiological, and clinical overlap with PDB and in two cases of early onset PDB-like disease. Likewise, genome wide association studies performed in unrelated PDB cases identified other potential predisposition genes and/or susceptibility loci. Thus, it is likely that polygenic factors are involved in the PDB pathogenesis in many individuals and that modifying genes may contribute in refining the clinical phenotype. Moreover, the contribution of somatic mutations of SQSTM1 gene and/or epigenetic mechanisms in the pathogenesis of skeletal pagetic abnormalities and eventually neoplastic degeneration, cannot be excluded. Indeed, clinical and experimental observations indicate that genetic susceptibility might not be a sufficient condition for the clinical development of PDB without the concomitant intervention of viral infection, in primis paramixoviruses, and/or other environmental factors (e.g., pesticides, heavy metals or tobacco exposure), at least in a subset of cases. This review summarizes the most important advances that have been made in the field of cellular and molecular biology PDB over the past decades.

Rechallenge of denosumab in advanced giant cell tumor of the bone after atypical femur fracture: A case report and review of literature

Giant cell tumor of the bone (GCTB) is a locally aggressive neoplasm where surgery is often curative. However, it can rarely give rise to distant metastases. Currently, the only available active therapeutic option for unresectable GCTB is denosumab, an anti-RANKL monoclonal antibody that dampens the aggressive osteolysis typically seen in this disease. For advanced/metastatic GCTB, denosumab should be continued lifelong, and although it is usually well tolerated, important questions may arise about the long-term safety of this drug. In fact, uncommon but severe toxicities can occur and eventually lead to denosumab discontinuation, such as atypical fracture of the femur (AFF). The optimal management of treatment-related AFF is a matter of debate, and to date, it is unknown whether reintroduction of denosumab at disease progression is a clinically feasible option, as no reports have been provided so far. Hereinafter, we present a case of a patient with metastatic GCTB who suffered from AFF after several years of denosumab; we describe the clinical features, orthopedic treatment, and oncological outcomes, finally providing the first evidence that denosumab rechallenge after AFF occurrence may be a safe and viable option at GCTB progression.

Giant Cell Tumor of the Second Metatarsal Managed with Ray Amputation: A Rare Case Report and Review of Literature

Introduction

The giant cell tumor of bone (GCTB), also known as an osteoclastoma or a myeloid sarcoma, is a benign local aggressive osteolytic bone tumor that primarily affects skeletally mature young adults typically 20-40 years of age. Giant cell tumors (GCTs) are usually solitary tumors and very rarely are found in the metatarsal bones. The characteristic histological appearance of GCT displays a high number of osteoclast-like multinucleated giant cells, which resulted in the classification "osteoclastoma" or "giant cell tumor."

Case Report

A 38-year-old male presented to the hospital with a firm swelling over the 2nd metatarsal slowly progressing over a period of 4 months, initial screening radiological investigations included X-rays, X-rays showed a tumorous growth involving the shaft of the 2nd metatarsal of the right foot, and the X-rays showed a characteristic soap bubble appearance. Magnetic resonance imaging. On gross assessment, the intraoperative sample showed that the GCTB has a dark brown-to-reddish appearance that is friable in texture. The gold standard for diagnosing a GCT is based on biopsy histopathological findings. The key histomorphologic feature is multinucleated giant cells.

Conclusion

Giant cell tumors are frequently locally aggressive with high recurrence percentage, hence, excision was done. Nowadays, early radiological screening techniques help early detection of such rare occurrence of tumors such as the GCT and appropriate management. In conclusion, the giant cell tumor of the bone is a unique presentation of stromal cell and hematopoietic interaction in the bone.

Epigenetic lockdown of CDKN1A (p21) and CDKN2A (p16) characterises the neoplastic spindle cell component of giant cell tumours of bone

Giant cell tumour of bone (GCTB) comprises the eponymous osteoclastic multinucleated giant cells eliciting bone lysis, a H3F3A-mutated neoplastic mononucleated fibroblast-like cell population and H3F3A-wild type mononucleated stromal cells. In this study, we characterised four new cell lines from GCTB. Furthermore, we compared the genome-wide DNA methylation profile of 13 such tumours and three further cell lines with giant cell rich lesions comprising three H3F3B-mutated chondroblastomas, three USP6-rearranged aneurysmal bone cysts, three non-ossifying fibromas, two hyperparathyroidism-associated brown tumours as well as mesenchymal stem cells, osteoblasts, and osteoclasts. In an unsupervised analysis, we delineated GCTB and chondroblastomas from the other analysed tumour entities. Using comparative methylation analysis, we demonstrated that the methylation pattern of the cell lines approximately equals that of H3F3A-mutated stromal cells in tissue. These patterns more resemble that of osteoblasts than that of mesenchymal stem cells, which argues for the osteoblast as the cell of origin of giant cell tumours of bone. Using enrichment analysis, we detected distinct hypermethylated clusters containing histone and collagen genes as well as target genes of the tumour suppressor p53. We found that the promotor regions of CDKN1A, CDKN2A and IGFBP3 are methylated more strongly in GCTB than in the other giant cell containing lesions, mesenchymal stem cells, osteoblasts, and osteoclasts (p<0.001). This hypermethylation correlates with the lower gene expression at the mRNA level for these three genes in the cell lines, the lack of p16 and p21 in these cell lines and the lower expression of p16 and p21 in GCTB. Overall, our analysis reveals characteristic DNA methylation patterns of giant cell tumours of bone and chondroblastomas and shows that cell lines of giant cell tumours of bone are a valid model for further analysis of H3F3A-mutated tumour cells. This article is protected by copyright. All rights reserved.

A Large Cavernous Sinus Giant Cell Tumor Invading Clivus and Sphenoid Sinus Masquerading as Meningioma: A Case Report and Literature Review

Giant cell tumor (GCT) of the bone is a rare benign, locally aggressive tumor that occurs in the epiphysis of long bones, especially the lower femur and the upper tibia. GCT of the bone of cranial origin is very rare, accounting for 1% of all GCT of the bone. We report the diagnosis, treatment, and immunohistochemistry of a rare case of intracranial GCT of the bone. We also review and summarize the imaging features, diagnostic markers, and current major treatment options for GCT of the bone. Our case and literature review emphasizes the importance of considering the full picture when making a diagnosis, rather than relying on imaging alone to make the diagnosis.

Giant Cell Tumor of Bone: A Single Center Study of 115 cases

•

Giant cell tumor of bone (GCTB) is a rarely metastasizing, locally aggressive tumor.

•

GCTB recurs frequently after intralesional curettage.

•

Denosumab is a potential neoadjuvant treatment option for borderline resectable lesions.

Background

Giant cell tumor of bone (GCTB) is a locally aggressive bone tumor that represents about 4–5% of all primary bone tumors. It is characterized by aggressive growth, possible recurrence after surgical treatment and, in rare cases, metastasis. Surgical management is the primary treatment and may include intralesional curettage with adjuvants or, in rare cases, wide resection. In recent years the monoclonal antibody denosumab has been introduced as a potential (neo-)adjuvant systemic treatment option for patients with borderline resectable or unresectable lesions. Currently several studies reported that the use of denosumab prior to curettage possibly increase the risk of local recurrence.

Methods

In this retrospective study we reviewed 115 cases of GCT with a mean follow-up of 65.6 (24–404) months who underwent a surgical treatment with or without preoperative denosumab therapy in our institution. Potential risk factors for LR and complications were analyzed.

Results

The study includes 47 male (40.9%) and 68 female (59.1%) patients with a mean age of 33.9 (10–77) years and a mean follow-up of 65.6 (24–404) months. Denosumab was used in 33 (28.7%) cases, in 14 cases (12.2%) in a neoadjuvant setting and in 17 cases preoperatively before re-curettage (14.8%) after LR. In 105 cases (91.3%) an intralesional curettage was performed. The overall LR rate was 47.8% (55 cases). Patients who underwent intralesional curettage and bone cement augmentation without neoadjuvant denosumab treatment had LR in 42.2% (38/90) of the cases. Patients who underwent neoadjuvant denosumab treatment prior to curettage had LR in 28.6% (4/14). Re-recurrence was frequent in patients with neoadjuvant denosumab treatment who had LR after initial curettage (50%, 8/16). After wide resection and endoprosthetic replacement one case (20%) of local recurrence was detectable (1/5 cases).

Conclusions

GCTB recurs frequently after intralesional curettage and cement augmentation. While denosumab is a potential (neo-)adjuvant treatment option that might be used for lesions that are difficult to resect, surgeons should be aware that LR is still frequent.

Spontaneous Regression of Brown Tumor in a Patient Treated With Peritoneal Dialysis

A 52-year-old man, with a history of diabetic nephropathy and renal cancer, had been treated with peritoneal dialysis for four months before consulting our hospital. At the time of imaging evaluation, three years after surgery for renal cancer, fluorodeoxyglucose accumulation was found at the distal metaphysis of the left radius. After the biopsy, he was diagnosed with giant cell tumor of bone (GCTB), and surgery was scheduled. However, osteogenesis was observed in the images retaken before surgery. It was found that his intact parathyroid hormone level had been abnormally high four months prior to his visit to us but had subsequently normalized. The tissue obtained by re-biopsy revealed osteogenesis with the disappearance of multinucleated giant cells, suggesting a brown tumor (BT). The tumor was thought to have been caused by secondary hyperparathyroidism (HPT) associated with peritoneal dialysis. When osteolytic lesions mimicking GCTB are found, the possibility of BT should be considered based on comorbidities and clinical information.

Rechallenge of denosumab in jaw osteonecrosis of patients with unresectable giant cell tumour of bone: a case series analysis and literature review

Objectives

Giant cell tumour of bone (GCTB) is a rare tumour, generally managed with surgery. Treatment of the very rare unresectable advanced/metastatic GCTB is challenging and denosumab is the only current available medical option, an anti-RANKL monoclonal antibody inhibiting osteolysis. An uncommon but severe and treatment-limiting adverse event of denosumab is the osteonecrosis of the jaw (ONJ). The clinical management of GCTB patients stopping denosumab for medication-related (MR)-ONJ and the possible reintroduction of denosumab after MR-ONJ resolution is matter of debate. We performed a retrospective study to describe the incidence, clinical features and outcome of MR-ONJ in unresectable GCTB patients treated with denosumab at our Institution.

Design and setting

Retrospective, single-institutional study.

Participants

Adult patients receiving denosumab as antineoplastic therapy for GCTB and experiencing MR-ONJ at Fondazione IRCCS Istituto Nazionale Tumori of Milan between January 2008 and July 2019.

Main outcome measures

Incidence, time of onset and clinical features of MR-ONJ.

Results

29 patients with locally advanced and/or metastatic GCTB treated with denosumab were identified. At a median follow-up of 70 months (range 1–125), 4 (13.8%) patients experienced MR-ONJ while on treatment, after 125, 119, 85 and 41 months of denosumab, respectively. All patients showed an ongoing tumour stabilisation with denosumab at the MR-ONJ onset and in all cases denosumab was stopped. All four patients were treated with ozone therapy. Two are waiting for surgery, two were already operated on. Both of them experienced disease progression and were thus rechallenged with denosumab. One is still on therapy after 25 months. The other had an MR-ONJ relapse after 39 months and was treated again with ozone therapy and surgery. She is under surveillance, GCTB being currently stable.

Conclusion

A clinical algorithm of denosumab rechallenge after complete resolution of MR-ONJ in progressing GCTB patients should be prospectively validated.

Neurofibromatosis Type 1 With Cherubism-like Phenotype, Multiple Osteolytic Bone Lesions of Lower Extremities, and Alagille-syndrome: Case Report With Literature Survey

BACKGROUND/AIM

Neurofibromatosis type 1 (NF) is an autosomal dominant hereditary disease. The cardinal clinical findings include characteristic skeletal alterations. Difficulties in diagnosis and therapy can arise if an individual has further illnesses.

CASE REPORT

This is a case report of a 16-year-old patient affected by NF1. She also suffered from Alagille syndrome and the consequences of fetal alcohol exposure. The patient's facial phenotype showed findings that could be assigned to one or more of the known diseases. The patient was referred for treating a cherubism-like recurrent central giant cell granuloma (CGCG) of the jaw. The patient developed bilateral, multilocular non-ossifying fibromas (NOF) of the long bones of the lower extremity. Treatment of the skeletal lesions consisted of local curettage. While NOF regressed after surgery, the CGCG of the jaw remained largely unchanged. Extensive genetic tests confirmed a previously unknown germline mutation in the JAG1 gene, the germline mutation of the NF1 gene, and the somatic mutation in the NF1 gene in the diffuse plexiform neurofibroma, but not in the CGCG.

CONCLUSION

Assigning facial findings to a defined syndrome is ambiguous in many cases and especially difficult in patients who have multiple diseases that can affect the facial phenotype. Surgical therapy should be adapted to the individual findings.

Giant Cell Tumor of Bone: An Update

PURPOSE OF REVIEW

To highlight the new developments in the management of advanced giant cell tumor of bone, a rare locally aggressive benign tumor, which was traditionally managed with surgery alone by either curettage and local adjuvant therapy, wide resection, or marginal excision. Here, we review the current role of systemic therapy for management of locally advanced or metastatic giant cell tumor of bone (GCTB).

RECENT FINDINGS

The elucidation of the pathophysiology of giant cell tumor of bone, especially with regards to the role of nuclear factor kappa B ligand (RANKL), has led to the Food and Drug Administration (FDA) approval of denosumab in the management of locally advanced or metastatic GCTB. For advanced giant cell tumor where surgical resection alone can cause severe morbidity, the paradigm has shifted from local treatment alone to multidisciplinary management with the consideration of use of denosumab.

Mini-TrpRS is essential for IFNγ-induced monocyte-derived giant cell formation

Truncated tryptophanyl-tRNA synthetase (mini-TrpRS), like any other aminoacyl-tRNA synthetases, canonically functions as a protein synthesis enzyme. Here we provide evidence for an additional signaling role of mini-TrpRS in the formation of monocyte-derived multinuclear giant cells (MGCs). Interferon-gamma (IFNγ) readily induced monocyte aggregation leading to MGC formation with paralleled marked upregulation of mini-TrpRS. Small interfering (si)RNA, targeting mini-TrpRS in the presence of IFNγ prevented monocyte aggregation. Moreover, blockade of mini-TrpRS, either by siRNA, or the cognate amino acid and decoy substrate D-Tryptophan to prevent mini-TrpRS signaling, resulted in a marked reduction in expression of the purinergic receptor P2X 7 (P2RX7) in monocytes activated by IFNγ. Our findings identify mini-TrpRS as a critical signaling molecule in a mechanism by which IFNγ initiates monocyte-derived giant cell formation.

Hemorrhagic Giant Cell Tumor of the Occipital Skull Base: A Case Report and Literature Review

Giant cell tumor of bone is a benign but locally aggressive osteolytic neoplasm that represents 3% to 5% of all primary bone tumors, primarily found at the epiphyses of long bones. Less than 1% are of calvarial origin. Herein, we report a rare case of a nine-year-old girl with a hemorrhagic giant cell tumor of the left occipital skull base.

Preoperative denosumab treatment with curettage may be a risk factor for recurrence of giant cell tumor of bone

PURPOSE

Giant cell tumor of bone (GCTB) is a local aggressive bone tumor, histologically classified as intermediate malignancy. Recently, the RANKL inhibitor, denosumab, was developed as a novel and effective treatment option for GCTB. Since the risk of preoperative use of denosumab with curettage had been previously reported, this study aimed to investigate the relationship between recurrences and clinicopathological features associated with adjuvant denosumab treatment in GCTB.

METHODS

A total of 87 GCTB cases were treated at our institution. We reviewed 66 patients with conventional-type GCTB occurring in the extremities and analyzed 78 surgical treatments, including curettages and resections, with clinicopathological features and denosumab treatment.

RESULTS

GCTB lesions, including 66 primary and 12 recurring, underwent surgical treatment like curettage and resection. Recurrence-free survivals in 78 GCTB surgeries were 78.7% in 3 years and 71.9% in 5 years. In the resected cases of GCTBs, there was no recurrence either with or without denosumab. In curettage cases, 3-year recurrence-free survivals were 0.0% (n = 3) in preoperative treatment of denosumab, 66.7% (n = 6) in postoperative treatment, and 76.6% (n = 43) in no treatment. Interestingly, three preoperative treatment cases demonstrated low MIB-1 index despite 100% recurrence. The other clinicopathological factors did not contribute much to the risk of recurrence in curettage cases.

CONCLUSION

Our findings revealed the use of denosumab in GCTB, prior to curettage, to possibly increase the risk of local recurrence. Together with previous reports, our finding might provide information for beneficial treatment of GCTB.

Histone H3G34 Mutation in Brain and Bone Tumors

H3G34 mutations occur in both pediatric non-brainstem high-grade gliomas (G34R/V) and giant cell tumors of bone (G34W/L). Glioblastoma patients with G34R/V mutation have a generally adverse prognosis, whereas giant cell tumors of bone are rarely metastatic benign tumors. G34 mutations possibly disrupt the epigenome by altering H3K36 modifications, which may involve attenuating the function of SETD2 at methyltransferase. H3K36 methylation change may further lead to genomic instability, dysregulated gene expression pattern, and more mutations. In this chapter, we summarize the pathological features of each mutation type in its respective cancer, as well as the potential mechanism of their disruption on the epigenome and genomic instability. Understanding each mutation type would provide a thorough background for a thorough understanding of the cancers and would bring new insights for future investigations and the development of new precise therapies.

Giant cell tumor of bone at the proximal epiphysis of humerus in a skeletally immature patient: A case report

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Giant cell tumor of bone (GCTB) at proximal humerus in skeletally immature (SI) patients is rare.

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MRI and clinical evaluation are paramount for the GCTB diagnosis.

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Tumor resection with cementation and adjuvant therapy is described as GCTB treatment.

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GCTB should be suspected in all SI cases with enlarged proximal humerus lesions.

Introduction

Giant cell tumor of bone (GCTB) in skeletally immature (SI) patients are rare benign lesions that have locally aggressive growth pattern and high risk of recurrence. The presence of GCTB at the proximal epiphysis of humerus in SI patients has never been described in literature.

Presentation of case

This report shows the case of a 10-year-old SI male who presented with a GCTB at the proximal epiphysis of humerus that was treated with curettage, cement and adjuvant therapy.

Discussion

The presence of a lytic growing lesion at the proximal humerus in a SI patient should alert clinicians to consider GCTB in their differential diagnosis. The management of GCTB in SI patients is challenging for orthopaedic surgeons. Tumor resection with cementation and adjuvant therapy has been described as a method rationale to prevent the recurrence and preserve the joint function in SI patients with GCTB at the proximal epiphysis of humerus. Clinicians should continue to monitor these patients with radiographic imaging for possible recurrence, metastasis or growth plate injury.

Conclusion

Tumor resection with cementation and adjuvant therapy offers a treatment alternative to prevent the recurrence and preserve the joint function in SI patients with GCTB at the proximal epiphysis of humerus. The use of a prothesis in a SI patient should avoided if possible, to prevent implant-related complications and damage to the growth plate.

Giant cell tumor of the bone presenting as swelling of the thumb

We describe a giant cell tumor in a 74-year-old man who presented with pain and swelling in the left thumb. Radiographs of the left hand showed some lytic changes at the tip of the thumb. Magnetic resonance imaging suggested the diagnosis of giant cell tumor, which was later confirmed by biopsy. A good treatment response was achieved with disarticulation of the interphalangeal joint and amputation of the distal phalanx of the left thumb.

Giant Cell Tumor With Atypical Imaging Implying Osteosarcoma

Giant cell tumor (GCT) of bone is benign and typically shows osteolytic changes on x-ray, whereas osteosarcoma is malignant and generally shows osteolytic and osteoblastic mixed images. We experienced a rare case of GCT with atypical radiological findings. The tumor found in the right knee of a 15-year-old girl comprised a wide range of osteoblastic and osteolytic lesion in medial femur. Technetium uptake, however, was detected only in osteoblastic part, and immunohistochemical staining of biopsy showed diffusely positive for antihistone G34W and almost negative for Ki-67. These results strongly suggest the tumor was GCT.

Exploring the Proteomic Alterations from Untreated and Cryoablation and Irradiation Treated Giant Cell Tumors of Bone Using Liquid-Chromatography Tandem Mass Spectrometry

Giant cell tumors of bone (GCT) are benign tumors that show a locally aggressive nature and affect bones' architecture. Recently, cryoablation and irradiation treatments have shown promising results in GCT patients with faster recovery and less recurrence and metastasis. Therefore, it became a gold standard surgical treatment for patients. Hence, we have compared GCT-untreated, cryoablation, and irradiation-treated samples to identify protein alterations using high-frequency liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS). Our label-free quantification analysis revealed a total of 107 proteins (p < 0.01) with 26 up-regulated (< 2-folds to 5-fold), and 81 down-regulated (> 0.1 to 0.5 folds) proteins were identified from GCT-untreated and treated groups. Based on pathway analysis, most of the identified up-regulated proteins involved in critical metabolic functions associated with tumor proliferation, angiogenesis, and metastasis. On the other hand, the down-regulated proteins involved in glycolysis, tumor microenvironment, and apoptosis. The observed higher expressions of matrix metalloproteinase 9 (MMP9) and TGF-beta in the GCT-untreated group associated with bones' osteolytic process. Interestingly, both the proteins showed reduced expressions after cryoablation treatment, and contrast expressions identified in the irradiation treated group. Therefore, these expressions were confirmed by immunoblot analysis. In addition to these, several glycolytic enzymes, immune markers, extracellular matrix (ECM), and heat shock proteins showed adverse expressions in the GCT-untreated group were identified with favorable regulations after treatment. Therefore, the identified expression profiles will provide a better picture of treatment efficacy and effect on the molecular environment of GCT.

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.

Giant cell tumor stromal cells: osteoblast lineage-derived cells secrete IL-6 and IL-10 for M2 macrophages polarization

Background

The giant cell tumor (GCT) is a benign tumor which consists of three types cells: mononuclear histiocytic cells (MNHCs), multinuclear giant cells (MNGCs), and GCT stromal cells (GCTSCs). Numerous studies claim that GCTSCs have mesenchymal stem cells (MSCs) characters and play an important role in osteoclastogenesis; however, there are no research studies concerning macrophage polarization among GCT, which can be regarded as an ingredient for tumor aggression.

Method

We tested the effect of GCTSCs from three GCT samples which were collected from patients on proliferation, apoptosis and polarization of macrophage.

Result

In this article, we verified that GCTSCs expressed MSCs markers and had higher proliferation and relative lower differentiation abilities compared with BMMSCs. What's more, we found a higher proportion of M2 macrophages among neoplasm. Co-culturing GCTSCs with macrophages resulted in prominent macrophage M2 polarization and increased the release of IL-6 (Interleukin-6) and IL-10 (Interleukin-10)from GCTSCs. In conclusion, GCTSCs, as originating from MSCs, can secret IL-6 and IL-10, which may play a significant role in macrophage M2 polarization.

Successful Treatment with Denosumab of a Giant Cell Tumor of Bone in the Iliac Bone of an 84-Year-Old Man

We report a case of GCTB in an 84-year-old Japanese man who had a tumor in his left iliac bone and was treated safely with denosumab. The patient noticed a painful mass, with gradual enlargement, in his left low back next to the iliac region. Magnetic resonance imaging revealed that the tumor measured 94 × 66 × 90 mm and was located in the left iliac bone. Histologically, the tumor was composed of proliferative oval-shaped mononuclear cells, admixed with large number of osteoclast-like giant cells. Immunohistochemically, a strong positivity for histone 3.3 G34W mutant protein was observed in the nuclei of the mononuclear cells, confirming the diagnosis of GCTB. Because it was considered as unresectable tumor, the patient was treated with denosumab without any side effects.

The two faces of giant cell tumor of bone

Giant cell tumor (GCT) is a bone-destructive benign neoplasm characterized by distinctive multinucleated osteoclast-like giant cells with osteolytic properties distributed among neoplastic stromal cells. GCT is locally aggressive with progressive invasion of adjacent tissues and occasionally displays malignant characteristics including lung metastasis. GCT is characterized genetically by highly recurrent somatic mutations at the G34 position of the H3F3A gene, encoding the histone variant H3.3, in stromal cells. This leads to deregulated gene expression and increased proliferation of mutation-bearing cells. However, when GCT complicates Paget disease of bone (GCT/PDB) it behaves differently, showing a more malignant phenotype with 5-year survival less than 50%. GCT/PDB is caused by a germline mutation in the ZNF687 gene, which encodes a transcription factor involved in the repression of genes surrounding DNA double-strand breaks to promote repair by homologous recombination. Identification of these driver mutations led to novel diagnostic tools for distinguishing between these two tumors and other osteoclast-rich neoplasms. Herein, we review the clinical, histological, and molecular features of GCT in different contexts focusing also on pharmacological treatments.

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.

Image-Guided Percutaneous Management of Skull and Spine Giant Cell Tumors: Case Report of 2 Challenging Cases Successfully Treated with Doxycycline Sclerotherapy

Background

A giant cell tumor (GCT) of bone is a benign, locally aggressive tumor that is often challenging to treat. When complete resection is not possible, curettage with or without adjuvants is the most common treatment. The high frequency of local recurrence and risk of injury to adjacent structures can limit this surgical approach, especially with skull and spine lesions.

Case Description

We report 2 cases of axial skeleton GCTs, 1 in the skull of a 58-year-old woman in whom operative management failed, who experienced local recurrence, and 1 in the cervical spine of an 8-year-old girl that grew extracompartmentally to surround her brachial plexus. Both patients were referred to us because of the surgically challenging nature of their tumors. After completion of the same percutaneous doxycycline sclerotherapy protocol previously described for aneurysmal bone cysts (ABCs), both patients were considered cured and were able to return to normal activities without loss of pretreatment function. After 4 and 10 years of follow-up, respectively, there has been no tumor recurrence in either patient.

Conclusions

We successfully treated 2 patients with very challenging axial skeleton GCTs using a percutaneous doxycycline sclerotherapy protocol previously shown to have success with ABCs. We believe that this minimally invasive procedure should be considered a potential alternative treatment for GCTs, especially axial skeleton lesions, which may not be easily approached with standard surgical techniques.

In situ cell cycle analysis in giant cell tumor of bone reveals patients with elevated risk of reduced progression-free survival

OBJECTIVE

Giant cell tumor of bone (GCTB) is a frequently recurring locally aggressive osteolytic lesion, where pathological osteoclastogenesis and bone destruction are driven by neoplastic stromal cells. Here, we studied if cell cycle fractions within the mononuclear cell compartment of GCTB can predict its progression-free survival (PFS).

METHODS

154 cases (100 primaries and 54 recurrent) from 139 patients of 40 progression events, was studied using tissue microarrays. Ploidy and in situ cell cycle progression related proteins including Ki67 and those linked with replication licensing (mcm2), G1-phase (cyclin D1, Cdk4), and S-G2-M-phase (cyclin A; Cdk2) fractions; cell cycle control (p21^waf1) and repression (geminin), were tested. The Prentice-Williams-Peterson (PWP) gap-time models with the Akaike information criterion (AIC) were used for PFS analysis.

RESULTS

Cluster analysis showed good correlation between functionally related marker positive cell fractions indicating no major cell cycle arrested cell populations in GCTB. Increasing hazard of progression was statistically associated with the elevated post-G1/S-phase cell fractions. Univariate analysis revealed significant negative association of poly-/aneuploidy (p < 0.0001), and elevated cyclin A (p < 0.001), geminin (p = 0.015), mcm2 (p = 0.016), cyclin D1 (p = 0.022) and Ki67 (B56: p = 0.0543; and Mib1: p = 0.0564 -strong trend) positive cell fractions with PFS. The highest-ranked multivariate interaction model (AIC = 269.5) also included ploidy (HR 5.68, 95%CI: 2.62-12.31, p < 0.0001), mcm2 (p = 0.609), cyclin D1 (HR 1.89, 95%CI: 0.88-4.09, p = 0.105) and cyclin A (p < 0.0001). The first and second best prognostic models without interaction (AIC = 271.6) and the sensitivity analysis (AIC = 265.7) further confirmed the prognostic relevance of combining these markers.

CONCLUSION

Ploidy and elevated replication licensing (mcm2), G1-phase (cyclin D1) and post-G1 phase (cyclin A) marker positive cell fractions, indicating enhanced cell cycle progression, can assist in identifying GCTB patients with increased risk for a reduced PFS.

Endothelin-1 Activates the Notch Signaling Pathway and Promotes Tumorigenesis in Giant Cell Tumor of the Spine

STUDY DESIGN

Experimental study.

OBJECTIVE

To examine the role of endothelin-1 (ET-1) and the Notch signaling pathway in giant cell tumor (GCT) of the spine.

SUMMARY OF BACKGROUND DATA

Previously published studies have shown that the Notch signaling pathway has a role in tumor invasion and that ET-1 is involved in tumor invasion and angiogenesis. However, the roles of both Notch signaling and ET-1 in GCT of the spine remain unknown.

METHODS

Expression of ET-1 in tissue samples from patients with spinal GCT, and adjacent normal tissue, were analyzed by immunohistochemistry and western blot. GCT stromal cells (GCTSCs) were isolated and ET-1 expression was demonstrated by immunofluorescence. Cell viability and cell migration of GCTSCs and human vascular endothelial cells following ET-1 treatment were assessed using the cell counting kit-8 assay and a transwell assay. Receptor activator of nuclear factor kappa-B ligand (RANKL) and osteoprotegerin (OPG) mRNA expression was determined following ET-1 treatment of GCTSCs using quantitative real-time polymerase chain reaction. In GCTSCs treated with ET-1 and the ET-1 signaling antagonist, BQ-123, levels of cyclin D1, vascular endothelial growth factor, matrix metalloproteinase-2 and -9 (MMP-2 and MMP-9), Jagged1, Hes1, Hey2, and Notch intracellular domain were examined by western blot.

RESULTS

Compared with normal adjacent tissue, ET-1 was highly expressed in GCT tissue. In GCTSCs studied in vitro, treatment with ET-1 significantly increased GCTSC and human vascular endothelial cells growth and migration and increased the expression of RANKL and OPG, meanwhile the ratio of RANKL/OPG was increased, in GCTSCs, it upregulated the production of cyclin D1, vascular endothelial growth factor, MMP-2, MMP-9, Jagged1, Hes1, Hey2, and Notch intracellular domain expression in a dose-dependent manner. Treatment with BQ-123 reversed these effects.

CONCLUSION

In GCT of the spine, ET-1 showed increased expression. In cultured GCTSCs, ET-1 treatment activated the Notch signaling pathway.

LEVEL OF EVIDENCE

2.

[New aspects on giant cell tumor of bone]

A giant cell tumor of bone (GCTB) is one of the giant cell-rich lesions of bone and has to be differentiated from non-ossifying fibroma, aneurysmatic bone cyst, chondroblastoma, "brown tumor" and osteosarcoma containing giant cells. A hallmark of GCTB is the presence of the distinct histone 3 (H3F3A) mutation G34W and its detection either by sequencing methods or using immunohistochemistry with a novel antibody against this mutational site. Worrisome is the fact that under denosumab therapy a histological change of the lesions can be seen and there are first reports of sarcomas arising after therapy. When diagnosing giant cell-rich lesions, pathologists should be aware of the various differential diagnoses and morphological spectrum within GCTB.

Investigation on distal femoral strength and reconstruction failure following curettage and cementation: In-vitro tests with finite element analyses

Cement augmentation following benign bone tumor surgery, i.e. curettage and cementation, is recommended in patients at high risk of fracture. Nonetheless, identifying appropriate cases and devices for augmentation remains debatable. Our goal was to develop a validated biomechanical tool to: predict the post-surgery strength of a femoral bone, assess the precision and accuracy of the predicted strength, and discover the mechanisms of reconstruction failure, with the aim of finding a safe biomechanical fixation. Tumor surgery was mimicked in quantitative-CT (QCT) scanned cadaveric human distal femora, and subsequently tested in compression to measure bone strength (F_Exp). Finite element (FE) models considering bone material non-homogeneity and non-linearity were constructed to predict bone strength (F_FE). Analyses of contact, damage, and crack initiation at the bone-cement interface (BCI) were completed to investigate critical failure locations. Results of paired t-tests did not show a significant difference between F_Exp and F_FE (P > 0.05); linear regression analysis resulted in good correlation between F_Exp and F_FE (R² = 0.94). Evaluation of the models precision using linear regression analysis yielded R² = 0.89, with the slope = 1.08 and intercept = -324.16 N. FE analyses showed the initiation of damage and crack and a larger cement debonding area at the proximal end and most interior part of BCI, respectively. Therefore, we speculated that devices that reinforce critical failure locations offer the most biomechanical advantage. The QCT-based FE method proved to be a reliable tool to predict distal femoral strength, identify some causes of reconstruction failure, and assist in a safer selection of fixation devices to reduce post-operative fracture risk.

Histone H3 Mutations: An Updated View of Their Role in Chromatin Deregulation and Cancer

In this review, we describe the attributes of histone H3 mutants identified in cancer. H3 mutants were first identified in genes encoding H3.3, in pediatric high-grade glioma, and subsequently in chondrosarcomas and giant cell tumors of bone (GCTB) in adolescents. The most heavily studied are the lysine to methionine mutants K27M and K36M, which perturb the target site for specific lysine methyltransferases and dominantly perturb methylation of corresponding lysines in other histone H3 proteins. We discuss recent progress in defining the consequences of these mutations on chromatin, including a newly emerging view of the central importance of the disruption of H3K36 modification in many distinct K to M histone mutant cancers. We also review new work exploring the role of H3.3 G34 mutants identified in pediatric glioma and GCTB. G34 is not itself post-translationally modified, but G34 mutation impinges on the modification of H3K36. Here, we ask if G34R mutation generates a new site for methylation on the histone tail. Finally, we consider evidence indicating that histone mutations might be more widespread in cancer than previously thought, and if the perceived bias towards mutation of H3.3 is real or reflects the biology of tumors in which the histone mutants were first identified.

Surgical Management of Giant Cell Tumor Involving the Lateral Skull Base

The aim of the study is to discuss the current management options for intra- and extra-cranial communication giant cell tumor of the lateral skull base and perform a review of the literature. A total of 6 patients with giant cell tumor of the lateral skull base were retrospectively enrolled in the study. The principal complaints, imaging manifestations, surgical resection and reconstruction of intra- and extra-cranial communication defects for the diseases were discussed. There were 2 males and 4 females. The most of principal complaints were discomfort or pain in the temporomandibular joint in 5 cases (83.3%). Imaging examination showed invasion of the temporal bone alone in 3 cases (50.0%) and both temporal bone and sphenoid bone involvement in 3 cases (50.0%). C-shaped preauricular infratemporal fossa approach was used for tumour removal and gross total resection was done in all 6 cases. The pedicled temporal muscle fascial flap was used to reconstruct the intra- and extra-cranial communication defect of the lateral skull base. The conclusion is that giant cell tumor is a benign tumor but is also locally aggressive. Gross total resection is the most commonly recommended treatment choice for giant cell tumor of the skull and can achieve good treatment outcomes. The temporalis muscle flap is a good alternative choice for reconstruction of the defect.

Bone tumours around the elbow: a rare entity

Bone tumours around the elbow are rare. Even nowadays diagnostic dilemmas and delays are common. During recent decades the management and prognosis of patients with elbow bone tumours has improved significantly.Benign tumours can be treated using minimally invasive procedures, whereas malignant ones require a multidisciplinary team approach based on an adjuvant therapeutic regimen of chemotherapy, radiotherapy and limb salvage procedures.This article reviews the most commonly encountered elbow bone tumours and their management. Cite this article: EFORT Open Rev 2019;4:133-142. DOI: 10.1302/2058-5241.4.180086.

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.