Multinucleated giant cells in various forms of giant cell containing lesions of the jaws express features of osteoclasts

Maxillary Aneurysmal Bone Cyst in a Young Dog-A Case Report

This case report describes an aneurysmal bone cyst in the maxilla of a young dog. It describes the clinical presentation, diagnostics, management, and successful outcome of this highly unusual case. Bone cysts are described as benign, cavitated lesions within bone that are lined by reactive tissues. There is no epithelial lining in the lesions. Bone cysts usually contain hemorrhage or serosanguinous fluid. They usually appear in the long bones, and present as a swelling with or without pain.

Appearances can be deceptive - Innocuous swelling on the gingiva masking an aggressive lesion within the maxilla

The central giant cell granuloma displays a varied biologic behaviour ranging from simple reactive lesions to aggressive neoplasms. The pathogenicity still remains enigmatic and needs to be differentiated from other giant cell containing lesions. Both maxilla and mandible are affected and 80% involve the region anterior to the first premolar region. CGCL arises centrally within bone, whereas PGCG is a gingival soft tissue lesion. Clinical and radiographic correlation is required to rule out a peripheral giant cell granuloma. The case described here was a rare presentation of a large epulis clinically with involvement of maxilla radiographically and was histologically diagnosed as a central giant cell lesion.

Efficacy and Toxicity of Calcitonin Treatment in Children with Cherubism: A Single-Center Cohort Study

Cherubism is a rare autosomal dominant disease characterized by expansile osteolytic jawbone lesions. The effect and safety of off-label calcitonin treatment during the progressive phase of the disease are not well described. In this retrospective study, we present data on the radiological response and adverse effects of subcutaneously administered calcitonin in a cohort of nine cherubism children (three female, six male). Two of the nine patients underwent two separate treatment courses with a significant off-treatment interval in between; therefore, a total of 11 treatment courses with a mean duration of 17.9 months (range <1 to 35, SD 10.8) were studied. To measure the response, the cumulative volume of cherubism lesions was calculated from available three-dimensional imaging. The primary outcome was the change in the volume of lesions during calcitonin treatment and only assessed for the eight treatment courses with a minimal duration of 6 months. A statistically significant reduction in the mean cumulative volume of lesions was seen regardless of treatment duration. Average volume reduction was highest in the first half year of treatment, with a gradual, ongoing reduction thereafter. For the secondary outcome, the change in the cumulative volume of lesions after treatment cessation was assessed for the seven treatment courses with follow-up imaging available. After six of these seven treatment courses, the cumulative volume increased again but remained undoubtedly smaller than the initial volume at the start of therapy. Adverse effects were assessed for all 11 treatment courses and occurred in 73% of them. Most adverse effects were mild and low grade, with the most severe being one grade 3 symptomatic hypocalcemia requiring hospitalization and early treatment termination. Calcitonin treatment seems effective and tolerable in treating actively progressing cherubism in children. However, further research is required to better understand the pharmacological treatment of cherubism, including also other drugs, dosing, and protocols. © 2023 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Mucosal Soft Tissue Lesions

Mucosal soft tissue lesions are fairly common in the pediatric population. However, the precise prevalence is unknown. This is the result of the limited number of studies, the use of various diagnostic criteria in those studies, and the transient nature of commonly encountered lesions in this population. In this section, we seek to familiarize the pediatric pathologist with a sampling of mucosal soft tissue lesions encountered in pediatric patients, highlight key diagnostic features and correlations with systemic diseases should they exist.

Osteoclast-derived IGF1 induces RANKL production in osteocytes and contributes to pagetic lesion formation

We previously reported that measles virus nucleocapsid protein (MVNP) expression in osteoclasts (OCLs) of patients with Paget disease (PD) or targeted to the OCL lineage in MVNP-transgenic mice (MVNP mice) increases IGF1 production in osteoclasts (OCL-IGF1) and leads to development of PD OCLs and pagetic bone lesions (PDLs). Conditional deletion of Igf1 in OCLs of MVNP mice fully blocked development of PDLs. In this study, we examined whether osteocytes (OCys), key regulators of normal bone remodeling, contribute to PD. OCys in PDLs of patients and of MVNP mice expressed less sclerostin, and had increased RANKL expression compared with OCys in bones from WT mice or normal patients. To test whether increased OCL-IGF1 is sufficient to induce PDLs and PD phenotypes, we generated TRAP-Igf1 (T-Igf1) transgenic mice to determine whether increased IGF1 expression in the absence of MVNP in OCLs is sufficient to induce PDLs and pagetic OCLs. We found that T-Igf1 mice at 16 months of age developed PD OCLs, PDLs, and OCys, with decreased sclerostin and increased RANKL, similar to MVNP mice. Thus, pagetic phenotypes could be induced by OCLs expressing increased IGF1. OCL-IGF1 in turn increased RANKL production in OCys to induce PD OCLs and PDLs.

Giant Cells of Various Lesions Are Characterised by Different Expression Patterns of HLA-Molecules and Molecules Involved in the Cell Cycle, Bone Metabolism, and Lineage Affiliation: An Immunohistochemical Study with a Review of the Literature

Giant cells (GCs) are thought to originate from the fusion of monocytic lineage cells and arise amid multiple backgrounds. To compare GCs of different origins, we immunohistochemically characterised the GCs of reactive and neoplastic lesions (n = 47). We studied the expression of 15 molecules including HLA class II molecules those relevant to the cell cycle, bone metabolism and lineage affiliation. HLA-DR was detectable in the GCs of sarcoidosis, sarcoid-like lesions, tuberculosis, and foreign body granuloma. Cyclin D1 was expressed by the GCs of neoplastic lesions as well as the GCs of bony callus, fibroid epulis, and brown tumours. While cyclin E was detected in the GCs of all lesions, p16 and p21 showed a heterogeneous expression pattern. RANK was expressed by the GCs of all lesions except sarcoid-like lesions and xanthogranuloma. All GCs were RANK-L-negative, and the GCs of all lesions were osteoprotegerin-positive. Osteonectin was limited to the GCs of chondroblastoma. Osteopontin and TRAP were detected in the GCs of all lesions except xanthogranuloma. RUNX2 was heterogeneously expressed in the reactive and neoplastic cohort. The GCs of all lesions except foreign body granuloma expressed CD68, and all GCs were CD163- and langerin-negative. This profiling points to a functional diversity of GCs despite their similar morphology.

A Comparative Clinicopathological Study of Giant Cell Tumour (GCT), Central Giant Cell Granuloma (CGCG) and Peripheral Giant Cell Granuloma (PGCG)

Objective

To evaluate and compare the clinicopathological features of giant cell tumour (GCT), central giant cell granuloma (CGCG) and peripheral giant cell granuloma (PGCG).

Material and methods

From 2006 to 2016, all histopathologically diagnosed cases of GCT were retrieved from the Department of Pathology, T.N.M.C, Mumbai and CGCG and PGCG were retrieved from the Department of Oral Pathology, Nair Hospital Dental College, Mumbai. Statistical analysis of the clinicopathological features was done using SPSS v 21.0, IBM. Intergroup comparison of all variables was done using t test for two groups, whereas, Kruskal-Wallis test and one-way ANOVA were done for more than two groups.

Results

Twelve cases of GCT, 31 cases of CGCG and 39 cases of PGCG were reported over 11 years. The mean age of occurrence for GCT, CGCG and PGCG was 30.41 years, 27.69 years and 34.03 years, respectively. GCT was seen in long bones and CGCG and PGCG showed mandible predilection. Histologically, GCT showed evenly distributed giant cells with aggregated nuclei, whereas CGCG and PGCG showed aggregated giant cells with evenly distributed nuclei. The mean value of the number of giant cells and nuclei within giant cells was maximum in GCT (27.33, 33.50) followed by CGCG (23.56, 15.51) and PGCG (21.45, 11.32).

Conclusion

The clinicopathological differences between GCT, CGCG and PGCG suggest that each one of these entities represent biologically different lesions.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12663-022-01724-3.

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.

Hybrid odontogenic lesions: A case series of a rare entity

Background

The occurrence of hybrid odontogenic lesions with two or more morphologically distinct components is a rare phenomenon and poses a diagnostic challenge. We aimed to study the clinical, radiological, and pathological features and behavior of hybrid odontogenic lesions, to enhance awareness about these rare lesions.

Method

Hematoxylin and Eosin slides of hybrid odontogenic lesions diagnosed between January 01, 2012 and December 31, 2020, were reviewed. Demographic and radiological information were obtained from the patient's medical records.

Results

8 cases were diagnosed with a mean age of 19.1 years and male to female ratio of 1:1.7. Involvement of mandible was more common (n = 5) as compared to maxilla (n = 3). All patients presented with swelling for an average of 9.75 months (3-25 months) duration. Bleeding, loose teeth, pain and facial asymmetry were reported in 5,3, 3, and 2 cases, respectively. Radiologically, 7 cases were well demarcated, 75% cases (n = 6) were radiolucent, and average radiological size was 4.8 cm. All patients were managed with surgery alone. 5 cases (62.5%) underwent enucleation and curettage, while local excision, en-block resection and segmental mandibulectomy were performed in 1 case each. Histologically, ossifying fibroma/cemento-ossifyiong fibroma were the most lesion, occurring in 5 cases (62%), followed by giant cell granuloma like lesions (GCG) i.e., central and peripheral giant cell granuloma (n = 3), Adenomatoid Odontogenic tumor (AOT) (n = 2), and DC (n = 2), ameloblastic fibroma (AF) (n = 1), Ameloblastoma (n = 1), calcifying odontogenic cyst (COC) (n = 1), and complex odontoma (n = 1). No evidence of recurrence was noted after 4-99 months of surgery (mean: 32.9) in cases with available data (n = 7). Long-term complaints included facial asymmetry (n = 2) and pain (n = 1).

Conclusion

Most hybrid odontogenic lesions affect young females in the second decade of life and commonly show COF and OF as hybrid components. A conservative approach to management appears adequate.

Fibrous dysplasia associated with peripheral giant cell granoluma in maxilla in a young patient, a case report of rare hybrid lesion

Benign fibro-osseous lesions are a diverse range of entities that have distinct clinical and radiographic features. They can occur as solitary lesions or concomitant with other pathologies as hybrid lesions. Fibrous dysplasia (FD) accompanied by central giant cell granuloma (CGCG), peripheral giant cell granuloma (PGCG) or peripheral ossifying fibroma (POF) as hybrid lesions, is reported very rarely in the literature. Although we were unable to find any reports of FD with PGCG as a hybrid lesion. Fibro-osseous lesions have certain histopathological features in common with PGCG including multinucleated giant cells. Here we report a 28 year old female with a painless, slow growing and pedunculated swelling of the maxilla for 18 months. Differential diagnosis consisted of FD, cemento-ossifying fibroma (COF), chondrosarcoma and probable PGCG considering radiographic and clinical investigations. Histopathologic findings revealed PGCG and FD as a hybrid lesion. The combination of PGCG and FD has not been reported in the literature so far.

Integrated proteomics, phosphoproteomics and metabolomics analyses reveal similarities amongst giant cell granulomas of the jaws with different genetic mutations

BACKGROUND

Giant cell granuloma of the jaws are benign osteolytic lesions of the jaws. These lesions are genetically characterized by mutually exclusive somatic mutations at TRPV4, KRAS, and FGFR1, and a fourth molecular subgroup which is wild-type for the three mutations. Irrespective of the molecular background, giant cell granulomas show MAPK/ERK activation. However, it remains unclear if these mutations lead to differences in their molecular signaling in giant cell granulomas.

METHODS

Metabolomics, proteomics and phosphoproteomics analyses were carried out in formalin-fixed paraffin-embedded samples of giant cell granuloma of the jaws. The study cohort consisted of five lesions harboring mutations in FGFR1, six in KRAS, five in TRPV4 and five that were wild-type for these mutations.

RESULTS

Lesions harboring KRAS or FGFR1 mutations showed overall similar proteomics and metabolomics profiles. In all four groups, metabolic pathways showed similarity in apoptosis, cell signaling, gene expression, cell differentiation and erythrocyte activity. Lesions harboring TRPV4 mutations showed a greater number of enriched pathways related to tissue architecture. On the other hand, the wild-type group presented increased number of enriched pathways related to protein metabolism compared to the other groups.

CONCLUSION

Despite some minor differences, our results revealed an overall similar molecular profile among the groups with different mutational profile at the metabolic, proteic and phosphopeptidic levels. This article is protected by copyright. All rights reserved.

Multiple versus solitary giant cell lesions of the jaw: Similar or distinct entities?

The majority of giant cell lesions of the jaw present as a solitary focus of disease in bones of the maxillofacial skeleton. Less frequently they occur as multifocal lesions. This raises the clinical dilemma if these should be considered distinct entities and therefore each need a specific therapeutic approach. Solitary giant cell lesions of the jaw present with a great diversity of symptoms. Recent molecular analysis revealed that these are associated with somatic gain-of-function mutations in KRAS, FGFR1 or TRPV4 in a large component of the mononuclear stromal cells which all act on the RAS/MAPK pathway. For multifocal lesions, a small group of neoplastic multifocal giant cell lesions of the jaw remain after ruling out hyperparathyroidism. Strikingly, most of these patients are diagnosed with jaw lesions before the age of 20 years, thus before the completion of dental and jaw development. These multifocal lesions are often accompanied by a diagnosis or strong clinical suspicion of a syndrome. Many of the frequently reported syndromes belong to the so-called RASopathies, with germline or mosaic mutations leading to downstream upregulation of the RAS/MAPK pathway. The other frequently reported syndrome is cherubism, with gain-of-function mutations in the SH3BP2 gene leading through assumed and unknown signaling to an autoinflammatory bone disorder with hyperactive osteoclasts and defective osteoblastogenesis. Based on this extensive literature review, a RAS/MAPK pathway activation is hypothesized in all giant cell lesions of the jaw. The different interaction between and contribution of deregulated signaling in individual cell lineages and crosstalk with other pathways among the different germline- and non-germline-based alterations causing giant cell lesions of the jaw can be explanatory for the characteristic clinical features. As such, this might also aid in the understanding of the age-dependent symptomatology of syndrome associated giant cell lesions of the jaw; hopefully guiding ideal timing when installing treatment strategies in the future.

Towards better understanding of giant cell granulomas of the oral cavity

Giant cell granulomas are enigmatic lesions of the oral cavity characterised by a peculiar combined proliferation of mononuclear and multinucleated giant cells in a mesenchymal stromal background. Central and peripheral giant cell granulomas may have similar pathogenesis and histology but differ in their location and biological behaviour. It is important to differentiate them from other giant cell lesions that can occur in the oral cavity, such as giant cell tumour of the bone, aneurysmal bone cyst, brown tumour of hyperparathyroidism, and giant cell lesions of Ramon syndrome, Noonan syndrome, neurofibromatosis and Jaffe-Campanacci syndrome. A recent insight into their molecular genetics and pathogenesis, with identification of KRAS, FGFR1 and TRPV4 mutations, allows for better diagnostic differentiation and opens the door to the use of pathway inhibitors in the treatment of recurrent or dysmorphic lesions. In this review, we provide an updated summary of the clinical and pathological features of oral cavity giant cell granulomas that help with their precise diagnosis and management.

Osteoclast-derived IGF1 is required for pagetic lesion formation in vivo

We report that transgenic mice expressing measles virus nucleocapsid protein (MVNP) in osteoclasts (OCLs) (MVNP mice) are Paget's disease (PD) models and that OCLs from patients with PD and MVNP mice express high levels of OCL-derived IGF1 (OCL-IGF1). To determine OCL-IGF1's role in PD and normal bone remodeling, we generated WT and MVNP mice with targeted deletion of Igf1 in OCLs (Igf1-cKO) and MVNP/Igf1-cKO mice, and we assessed OCL-IGF1's effects on bone mass, bone formation rate, EphB2/EphB4 expression on OCLs and osteoblasts (OBs), and pagetic bone lesions (PDLs). A total of 40% of MVNP mice, but no MVNP/Igf1-cKO mice, had PDLs. Bone volume/tissue volume (BV/TV) was decreased by 60% in lumbar vertebrae and femurs of MVNP/Igf1-cKO versus MVNP mice with PDLs and by 45% versus all MVNP mice tested. Bone formation rates were decreased 50% in Igf1-cKO and MVNP/Igf1-cKO mice versus WT and MVNP mice. MVNP mice had increased EphB2 and EphB4 levels in OCLs/OBs versus WT and MVNP/Igf1-cKO, with none detectable in OCLs/OBs of Igf1-cKO mice. Mechanistically, IL-6 induced the increased OCL-IGF1 in MVNP mice. These results suggest that high OCL-IGF1 levels increase bone formation and PDLs in PD by enhancing EphB2/EphB4 expression in vivo and suggest OCL-IGF1 may contribute to normal bone remodeling.

Hybrid ameloblastoma and central giant cell lesion: Challenge of early diagnosis

Hybrid lesions encompass the occurrence of different entities in one lesion. A 67-year-old woman was referred to the Oral and Maxillofacial Surgery Service for treatment of mandibular Central Giant Cell Lesion (CGCL) previously diagnosed. Intraoral examination revealed edentulism and a painless swelling extending from the alveolar ridge to the buccal vestibule with hard consistency covered by normal mucosae, with unknown duration. Panoramic radiograph revealed a large, multilocular and well-defined radiolucent lesion extending from the region of left mandibular lateral incisor teeth to right mandibular first molar with no evidence of osseous perforation. Initially, a treatment with intralesional injection of corticosteroids was performed. After 18 months of treatment, an increase in size of the osteolytic lesion was noted. An incisional biopsy was carried out and the microscopic examination revealed a unicystic ameloblastoma associated to CGCL. It was performed marsupialization and later the enucleation of residual lesion. The follow-up remains being performed.

Key words:Hybrid lesion, central giant cell lesion, ameloblastoma.

A Comparative Analysis of p63 Expression in Giant Cell Tumour (GCT), Central Giant Cell Granuloma (CGCG) and Peripheral Giant Cell Granuloma (PGCG)

Giant cell tumour (GCT) is locally aggressive benign neoplasm of long bones whereas giant cell granulomas; central giant cell granuloma (CGCG) and peripheral giant cell granuloma (PGCG); are tumour-like conditions of the oral cavity. This study aimed to evaluate and compare the immunohistochemical expression of p63 in GCT, CGCG, PGCG and determine whether p63 can be used as a diagnostic, prognostic and differential biomarker between these entities. Histopathologically diagnosed 10 cases of GCT, 20 cases of CGCG and 20 cases of PGCG were subjected to p63 immunohistochemical staining. The percentage of p63-positive cells was semi-quantitatively assessed on the whole section. Intergroup comparison was done using Kruskal-Wallis test and one-way ANOVA. The value p < 0.05 was considered to be statistically significant and value p < 0.01 was considered to be statistically highly significant. p63 immunoexpression was seen in 100% (10/10) cases of GCT whereas CGCG and PGCG revealed the complete absence of p63 immunopositivity. These results showed a highly significant difference in p63 expression between GCT, CGCG and PGCG (p < 0.01). No difference was noted between CGCG and PGCG. GCT is a distinct entity when compared with CGCG and PGCG. Even aggressive CGCG also did not show p63 immunopositivity, so it is not a prognostic marker. Also, p63 cannot differentiate between CGCG and PGCG.

KRAS mutations in implant-associated peripheral giant cell granuloma

OBJECTIVES

To investigate the molecular pathogenesis of implant-associated peripheral giant cell granuloma (IA-PGCG).

METHODS

A convenience sample of 15 IA-PGCG cases was selected. Hotspot mutations of KRAS, FGFR1, and TRPV4 genes, previously reported in conventional giant cell lesions of the jaws, were investigated by Sanger sequencing. As these mutations could activate MAPK/ERK pathway, the expression of phospho-ERK1/2 was also evaluated by immunohistochemistry.

RESULTS

KRAS mutations were detected in 8/15 (53.4%) samples. Similar to conventional peripheral giant cell granuloma, the KRAS mutations most frequently occurred in codon 146 (p.A146V, n = 3), followed by codon 12 (p.G12A and p.G12D, n = 1 each) and codon 14 (p.V14L, n = 1). Variants of unknown significance (VUS) were also detected in two cases, affecting codons 37 (p.E37K) and 127 (p.T127I). All samples showed wild-type (WT) sequences for FGFR1 and TRPV4 genes. Consistent with MAPK/ERK pathway activation, all mononuclear cells of the lesion showed strong staining for phospho-ERK1/2 protein in the immunohistochemical analysis.

CONCLUSIONS

KRAS mutations and activation of the MAPK-ERK signaling pathway occur in IA-PGCG. This is the first study to demonstrate cancer-associated gene mutations in a non-neoplastic reactive condition associated with dental implants.

Making sense of giant cell lesions of the jaws (GCLJ): lessons learned from next-generation sequencing

Next-generation sequencing has revealed mutations in several bone-related lesions and was recently used to uncover the genetic basis of giant cell lesions of the jaws (GCLJ). Consistent with their benign nature, GCLJ show a low tumor mutation burden. They also harbor somatic, heterozygous, mutually exclusive mutations in TRPV4, KRAS, or FGFR1. These signature mutations occur only in a subset of lesional cells, suggesting the existence of a 'landscaping effect', with mutant cells inducing abnormal accumulation of non-mutant cells that form the tumor mass. Osteoclast-rich lesions with histological similarities to GCLJ can occur in the jaws sporadically or in association with genetically inherited syndromes. Based on recent results, the pathogenesis of a subgroup of sporadic GCLJ seems closely related to non-ossifying fibroma of long bones, with both lesions sharing MAPK pathway-activating mutations. In this review, we extrapolate from these recent findings to contextualize GCLJ genetics and we highlight the therapeutic implications of this new information. © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Peri-implant peripheral giant cell lesions: report of 13 new cases and comparative histological and immunohistochemical analysis with peripheral and central giant cell lesions

BACKGROUND

Few cases or peri-implant peripheral giant cell lesions (PGCL) have been reported in the literature. The aim of this study was to report 13 new cases of peri-implant PGCL and compare the expression of smooth muscle actin, Bcl-2 protein, GLUT-1, CD68, osteoprotegerin, receptor activator of nuclear factor kappa-B, Ki-67 and CD34 in these cases with PGCL and central giant cell lesions (CGCL).

MATERIAL AND METHODS

Clinical data were retrieved from the laboratory records and histological analysis was performed using HE-stained slides. Immunohistochemical reactions for the above mentioned antibodies were performed and digitally scored.

RESULTS

Peri-implant PGCL mostly affected the posterior mandible of adult females. CD68 and Bcl-2 expressions were higher in conventional PGCL and CGCL than in peri-implant PGCL ( p=0.033 for CD68 and p<0.0001 for Bcl-2). Microvessel density was higher in conventional peripheral than in central and peri-implant PGCL ( p=0.002). Proliferative index of the mononuclear cells showed no statistically significant differences comparing the three groups but it was higher in peri-implant PGCL.

CONCLUSIONS

The current study demonstrated that peri-implant PGCL is more common in the posterior mandible of adult females. There were some differences in microvessel density, proliferative activity and expression of CD68 and Bcl-2 among conventional PGCL, peri-implant and CGCL. Further studies are encouraged to better understand these early findings.

Use of Denosumab in Children With Osteoclast Bone Dysplasias: Report of Three Cases

Denosumab has been used successfully to treat disease‐associated osteoclast overactivity, including giant cell tumor of bone. Given its mechanism of action, denosumab is a potent potential treatment of other osteoclast bone dysplasias including central giant cell granuloma (CGCG), aneurysmal bone cyst (ABC), and cherubism. Relatively little is known about the safety and efficacy of denosumab in patients with these conditions, especially in children. We report on 3 pediatric patients treated with denosumab over a 3‐year period at UCLA Medical Center (Los Angeles and Santa Monica, CA, USA): a 12‐year‐old with recurrent ABC of the pelvis, a 14‐year‐old with CGCG of the mandible, and a 12‐year‐old with cherubism. All were started on a 1‐year course of 15 doses 120 mg s.c., given monthly with two loading doses on day 8 and 15. All patients demonstrated rapid and pronounced clinical improvement while on denosumab, including a significant reduction in pain and sclerosis of lytic lesions on radiographs. Within 1 month of initiating therapy, 2 patients experienced hypocalcemia (Common Terminology Criteria for Adverse Events [CTCAE] grade 2) and hypophosphatemia, with 1 patient experiencing symptoms. One patient went on to experience symptomatic rebound hypercalcemia (CTCAE grade 4) 5 months after completing therapy, requiring bisphosphonates and calcitonin. For the second patient, we developed a schedule to wean denosumab involving the progressive lengthening of time between doses from 1 to 4 months in 1‐month increments before cessation. We found that denosumab therapy results in significant clinical and radiographic improvement for pediatric patients with nonresectable ABC, CGCG, and cherubism. Problems with serum calcium may be more common in younger patients, with symptomatic and protracted rebound hypercalcemia after cessation of therapy the most significant. We present a potential solution to this problem with progressive spacing of doses. Potential serious adverse events from alterations in calcium homeostasis should be explored in prospective clinical trials. © 2019 The Authors. JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research.

Effect of bergenin on RANKL-induced osteoclast differentiation in the presence of methylglyoxal

Methylglyoxal (MG), a highly reactive dicarbonyl compound, is a major precursor in the formation of advanced glycation end products, which are associated with diabetes-related diseases. Bergenin, an active constituent of plants of the genus Bergenia, exhibits multiple biological activities. This study evaluated the effect of bergenin on osteoclast differentiation and determined its mechanism of action. Bergenin reversed MG-inhibited tartrate-resistant acid phosphatase (TRAP) activity and decreased the bone resorption activity of osteoclasts. Quantitative RT-PCR revealed that bergenin decreased the expression of ERK1, Akt2, MMP-9, and OSTM1 genes in the presence of MG. Bergenin pretreatment yielded significant increases in intracellular calcium concentration, mitochondrial mass, mitochondrial membrane potential, and glyoxalase I reduced by MG. Additionally, bergenin decreased the formation of mitochondrial superoxide induced by MG. Detoxification of MG by bergenin may be a viable treatment for bone disorders in patients with diabetes.

Esthetic Management of Peripheral Giant Cell Granuloma Affecting a Dental Implant in the Esthetic Zone

INTRODUCTION

A size increase of the gingiva can be a manifestation of gingival disease. While gingival lesions can affect periodontal tissue, only few reports described the association between peripheral giant-cell granuloma (PGCG) with dental implants and their clinical management. Their clinical relevance is of a great interest since some lesions may lead to extensive bone resorption, esthetic alterations, or even tooth/implant loss. To the author's best knowledge, no specific guidelines for the treatment of PGCG affecting dental implant in the esthetic zone have been reported. The aim of this paper was to report an extensive PGCG associated with a dental implant in the esthetic area and its surgical management.

CASE PRESENTATION

A 39-year-old suffered from concussive trauma on her anterior maxillary dentition leading to an expanded, purplish soft tissue lesion surrounding the implant provisional crown on right central maxillary incisor. After complete lesion excision, the implant neck was carefully and gently debrided. Histological analysis confirmed the diagnosis of PGCG. The patient was then evaluated weekly for the first 3 weeks then monthly. No episodes of recurrence were identified. After 16 weeks of undisturbed healing, a soft tissue augmentation via tunnel technique was elected as the first treatment option to improve esthetics. Final implant restoration was delivered. Follow up at 22 months from biopsy excluded any recurrence of PGCG with stability of peri-implant soft tissues.

CONCLUSION

Excisional biopsy, careful removal of irritating factors, monitoring, and connective tissue grafting can esthetically improve a malpositioned implant and showed no recurrence over a period of 22 months.

An Overview of the Derivation and Function of Multinucleated Giant Cells and Their Role in Pathologic Processes

Monocyte lineage cells play important roles in health and disease. Their differentiation into macrophages is crucial for a broad array of immunologic processes that regulate inflammation, neoplasia, and infection. In certain pathologic conditions, such as foreign body reactions and peripheral inflammatory lesions, monocytes fuse to form large, multinucleated giant cells (MGCs). Currently, our knowledge of the fusion mechanisms of monocytes and the regulation of MGC formation and function in discrete pathologies is limited. Herein, we consider the types and function of MGCs in disease and assess the mechanisms by which monocyte fusion contributes to the formation of MGCs. An improved understanding of the cellular origins and metabolic functions of MGCs will facilitate their identification and ultimately the treatment of diseases and disorders that involve MGCs.

Molecular and cellular characterizations of human cherubism: disease aggressiveness depends on osteoclast differentiation

Background

Cherubism is a rare autosomal dominant disorder of the jaws caused by mutation of the SH3BP2 gene. The bone is replaced by a fibrous granuloma containing multinucleated giant cells. Cells of the cherubism granuloma have never been systematically analyzed. Hence, the aim of this study was to characterize the cells in human cherubism granulomas, to determine the osteoclastic characteristics of the multinucleated giant cells and to investigate the potential role of TNF-α in human cherubism.

Results

Seven granulomas were analyzed in pathology, molecular biology and immunohistochemistry. Granulomas were composed mainly of macrophages or osteoclasts within a fibroblastic tissue, with few lymphoid cells. Myeloid differentiation and nuclear NFATc1 localization were both associated with disease aggressiveness. OPG and RANKL immunohistochemical expression was unexpected in our specimens. Five granuloma cells were cultured in standard and osteoclastogenic media. In culture, cherubism cells were able to differentiate into active osteoclasts, in both osteoclastogenic and standard media. IL-6 was the major cytokine present in the culture supernatants.

Conclusion

Multinucleated giant cells from cherubism granulomas are CD68 positive cells, which differentiate into macrophages in non-aggressive cherubism and into osteoclasts in aggressive cherubism, stimulated by the NFATc1 pathway. This latter differentiation appears to involve a disturbed RANK-L/RANK/OPG pathway and be less TNF-α dependent than the cherubism mouse model.

Electronic supplementary material

The online version of this article (10.1186/s13023-018-0907-2) contains supplementary material, which is available to authorized users.

Radiographic Diagnosis of a Central Giant Cell Granuloma Using Advanced Imaging: Cone Beam Computed Tomography

Central giant cell granuloma (CGCG) is a benign non-neoplastic, proliferative intraosseous lesion of the jaw with an unknown etiology often diagnosed during the first two decades of life. The true nature of this lesion is controversial and remains elusive. Here, we report a case of central giant cell granuloma, diagnosed using cone-beam computed tomography (CBCT). A 21-year-old female presented to the clinic complaining of a painless swelling involving the right side of the mandible that had started one year previously. A CBCT scan revealed a well-defined, multilocular radiolucent lesion on the right side of the mandible extending from the molar region to the ramus with wispy septations. Wispy septations and undulating borders are some of the characteristic radiographic features of a central giant cell granuloma. The patient underwent an excisional biopsy. The biopsy revealed multinucleated giant cells in a fibrous stroma confirming our radiographic diagnosis of a central giant cell lesion.

Multi-nucleated cells use ROS to induce breast cancer chemo-resistance in vitro and in vivo

Although there is a strong correlation between multinucleated cells (MNCs) and cancer chemo-resistance in variety of cancers, our understanding of how multinucleated cells modulate the tumor micro-environment is limited. We captured multinucleated cells from triple-negative chemo-resistant breast cancers cells in a time frame, where they do not proliferate but rather significantly regulate their micro-environment. We show that oxidatively stressed MNCs induce chemo-resistance in vitro and in vivo by secreting VEGF and MIF. These factors act through the RAS/MAPK pathway to induce chemo-resistance by upregulating anti-apoptotic proteins. In MNCs, elevated reactive oxygen species (ROS) stabilizes HIF-1α contributing to increase production of VEGF and MIF. Together the data indicate, that the ROS-HIF-1α signaling axis is very crucial in regulation of chemo-resistance by MNCs. Targeting ROS-HIF-1α in future may help to abrogate drug resistance in breast cancer.

Brown tumor of the jaws as a manifestation of tertiary hyperparathyroidism: A literature review and case report

Brown tumor of the jaws is a manifestation of hyperparathyroidism consisting of osteolytic lesions that show proliferation of multinucleated giant cells in the maxilla and/or mandible. Differential diagnosis of these lesions from local central giant-cell granuloma is mandatory for the correct treatment of the patient. Radiographic and histopathological exams of the jaw lesion are not sufficient to determine the diagnosis, which requires laboratory tests including serum levels of calcium, alkaline phosphatase, parathyroid hormone (PTH) and phosphate, and radiographic examination of other bones as well, such as hand-wrist, pelvis, and femur. We present here a brief literature review focusing on the clinical and radiographic features, diagnostic criteria and treatment of brown tumor and also report a case of the disease affecting the jaw.

A comparative study of osteopontin and MMP-2 protein expression in peripheral and central giant cell granuloma of the jaw

Introduction

Oral peripheral and central giant cell granulomas are lesions with little-known etiology and pathogenesis.

Objective

The aim of this study was to compare matrix metalloproteinases-2 and osteopontin protein expression in the multinucleated giant cells and mononuclear cells of the peripheral and central giant cell granuloma lesions.

Methods

In this retrospective study, the presence of matrix metalloproteinases-2 and osteopontin in 37 cases of central giant cell granuloma and 37 cases of peripheral giant cell granuloma paraffin blocks were assessed by streptavidin-biotin immunohistochemistry. Independent sample t-test, Chi-square, Mann–Whitney tests and Spearman's rank correlation coefficient were used.

Results

The osteopontin was expressed in both multinucleated giant cells and mononuclear cells in all cases of peripheral and central giant cells granulomas. However, the matrix metalloproteinases-2 expression was positive in 86.5% of giant cells and it was positive in all of mononuclear cells in peripheral giant cells granuloma. In central giant cells granulomas, 91.8% of giant cells and all mononuclear cells were positive for matrix metalloproteinases-2 marker. Percentage and Intensity of staining were significantly higher in central than peripheral giant cells lesions, for both markers (p ˂ 0.05).

Conclusion

This study showed that the expression of osteopontin in giant cells supports the theory of osteolcastic nature of these cells. Also, the presence of osteopontin and matrix metalloproteinases-2 in mononuclear cells may indicate the monocyte-macrophage origin of these cells, as the differentiation of the precursors of the mononuclear stromal monocyte/macrophage to osteoclasts is possibly affected by the expression of osteolytic factors. Also, may be differences in biological behaviors of these lesions are associated with the level of osteopontin and matrix metalloproteinases-2 expression.

A Third Case of Glycogen Storage Disease IB and Giant Cell Tumour of the Mandible: A Disease Association or Iatrogenic Complication of Therapy

We report the third case of Glycogen Storage Disease type 1b (GSD 1b) with Giant Cell Tumour (GCT) of the mandible, associated with Granulocyte Colony Stimulating Factor (G-CSF) use. G-CSF in GSD 1b is indicated for persistent neutropaenia, sepsis, inflammatory bowel disease and severe diarrhoea. Our patient was 12 years old at GCT diagnosis and had been treated with G-CSF from 5 years of age. He underwent therapy with interferon followed by local resection which was successful in initial control of the disease. Histology demonstrated spindle shaped stromal cells together with numerous interspersed multinuclear osteoclastic giant cells. G-CSF has been hypothesized to induce osteoclastic differentiation and thus may be involved in the pathogenesis of GCT formation. At age 19 years he required a repeat operation for local recurrence. He currently continues on G-CSF and was commenced on denosumab for control of the GCT with no recurrence to date. A cause and effect relationship between G-CSF therapy and the development of GCT in GSD type 1b remains to be established.

Clinicopathologic and Molecular Characteristics of Familial Cherubism with Associated Odontogenic Tumorous Proliferations

Cherubism is a rare autosomal dominant condition affecting the jaws and caused by mutations in the gene encoding for the adapter protein SH3BP2 that maps to chromosome 4p16.3. Cherubism is characterized by symmetrically developing bone lesions in the maxilla and mandible. The lesions have been radiographically and histopathologically well-described. Here, we present a family with cherubism with two of its members featuring odontogenic tumorous proliferations in association with persistent central giant cell lesions (CGCL). Specifically, the proband, a 25-year-old male, developed a radiolucent lesion characterized histologically by central odontogenic fibroma-like proliferation in association with a CGCL component, while his mother, at age 57, was diagnosed with primary intraosseous odontogenic carcinoma with areas of benign fibro-osseous lesions. In both patients the lesions occurred in the anterior mandible and presented with clinical enlargement. The son underwent incisional biopsy and did not have additional treatment. His mother underwent extensive mandibulectomy due to widespread tumor. The son has two affected children with classic cherubism while a third child at age 5, had not shown any features of the disease. Mutation analysis of three affected members resulted in the identification of a heterozygous mutation in SH3BP2 (c.1244G>C; p.Arg415Pro). To the best of our knowledge, association of cherubism with odontogenic neoplastic lesions has hitherto not been reported in the literature, thus suggesting a relationship between cherubism with disturbed odontogenesis.

Pharmacological and surgical therapy for the central giant cell granuloma: A long-term retrospective cohort study

PURPOSE

This is a retrospective cohort study of patients with a central giant cell granuloma (CGCG) treated at a single center to assess and compare the different surgical and non-surgical approaches.

MATERIAL AND METHODS

A cohort with a single histologically proven non-syndrome-related CGCG was selected and reviewed. Patients were allocated to group I (surgery), group II (pharmacotherapy), and group III (pharmacotherapy and surgery). The primary outcome was long-term radiologic response using computed tomography. Secondary outcomes were intermediate radiologic responses and occurrence and severity of side effects.

RESULTS

Thirty-three subjects were included in the study. The surgical group (n = 4) included 1 patient with progression during follow-up and a relatively high post-surgical morbidity. Twenty-nine patients started on various pharmacological treatment regimens (groups II and III). Fourteen patients could be managed without additional surgery. One of these lesions showed progression during follow-up. The other 15 lesions underwent additional surgery, and none showed progression during follow-up. Interferon treatment was associated with the most side effects.

CONCLUSION

Pharmacological agents have a role in the treatment of aggressive and non-aggressive CGCGs by limiting the renewed progression during long-term follow up and the extent and morbidity of surgical treatment.

A Clinicopathological Study of 52 Feline Epulides

A retrospective study was performed to characterize 52 new cases of feline epulides between 1995 and 2001, with clinical and pathological results classified according to Head's histopathologic criteria for canine epulides. The incidence of the fibromatous, acanthomatous, ossifying, and giant cell epulis were respectively 57.7% (30/52), 7.7% (4/52), 5.8% (3/52), and 28.8% (15/52). Giant cell epulides presented significant differences in clinical behavior compared with the fibromatous type, including rapid growth ( P < .0001), presence of ulcerative changes ( P < .01), and rapid recurrence after surgery ( P < .01) from which euthanasia was judged necessary in 4 cases. Fifteen giant cell epulides were additionally examined in order to characterize the lesion both histochemically and immunohistochemically and to investigate the origin of the multinucleated giant cells (MGCs). Van Gieson staining showed osteoid and woven bone formation in 11 cases. Both the MGCs and a fraction of the mononuclear cells were positive for vimentin, tartrate-resistant acid phosphatase (TRAP), a commonly accepted marker for osteoclasts, and the polyclonal antibody receptor activator of nuclear factor κβ (RANK), a cytokine leading to the differentiation of osteoclast progenitors into mature osteoclasts in presence of its ligand. MGCs were negative for smooth muscle actin, MIB-1, and factor VIII. The giant cell epulis may be a variant of the fibromatous and ossifying epulis in which extensive ulceration and inflammation results in increased osteoclastic activity. The osteoclast-like giant cells are most likely formed from a monocyte/ macrophage-like osteoclast precursor that differentiates into osteoclasts under the influence of mononuclear osteoblast-like stromal cells.

Immunohistochemical detection of the receptor activator of nuclear factor Kappa B ligand and c-fos in giant cell granuloma

BACKGROUND

Giant cell granuloma (GCG) is an intraosseous giant cell fibroblastic lesion that predominantly affects the jaw bones in children and adults. Despite its frequent local progression and destructive effect, it is traditionally considered reparative or reactive in nature. The receptor activator of nuclear factor Kappa B ligand (RANKL), a member of the tumor necrosis factor family and the transcription factor c-fos play a major role in osteoclast proliferation and differentiation. In this study, we examined the expression of RANKL and c-fos in lesional tissues from seven patients with GCG.

MATERIALS AND METHODS

Automated immunohistochemical staining was performed on formalin-fixed paraffin-embedded sections from 7 cases, using antibodies against RANKL, c-fos and p53.

RESULTS

All tissues showed nuclear staining for c-fos and cytoplasmic staining for RANKL. The staining was strong, diffuse and observed in both mononuclear lesional cells and giant cells. No staining was observed with p53.

CONCLUSION

Expression of RANKL and c-fos in this lesion, similar to what has been reported in giant cell tumors of bone, suggests a similar pathogenesis and hence a potential response to anti-RANKL inhibitors. A larger study is needed to confirm these findings and define the relationship of this lesion to other giant cell-rich bone lesions.

Percutaneous Doxycycline Treatment of Juxtaphyseal Aneurysmal Bone Cysts

BACKGROUND

A recurrence rate of 19% to 23% has been reported in juxtaphyseal aneurysmal bone cysts (ABC) without en bloc resection or amputation. No percutaneous surgical techniques or drug treatments have demonstrated consistent bone healing with normal physeal growth and a recurrence rate of <19%. Doxycycline has properties that may make it an appropriate agent for percutaneous treatment of juxtaphyseal ABC in skeletally immature patients.

METHODS

We retrospectively reviewed 16 patients who underwent percutaneous treatment of ABCs with doxycycline from 2006 to 2011. The mean age was 7.1 years (range, 2 to 15 y). There were 16 treatment locations: humerus (9), tibia (3), fibula (2), femur (1), and ulna (1). Sixteen patients completed treatment involving 102 treatment sessions (2 to 14 sessions per patient). Treatment response was evaluated radiographically by measuring the lytic component, thickness of involved cortex, and signs of bony remodeling, and evidence of physeal growth arrest. Recurrence was indicated by new areas of lytic destruction after completion of treatment. The minimum follow-up was 18 months (mean, 39 mo).

RESULTS

All 16 patients demonstrated reduction in lytic destruction, bony healing, and bony remodeling. One patient demonstrated recurrent minimal lytic destruction after 20 months of observation. Seven patients (7/16, 44%) demonstrated physeal ABC involvement; 5 of 7 patients healed with a physeal bone bridge, all ≤15% of the physeal surface area, 1 with mild central physeal deformity. All patients with focal transphyseal ABC involvement (4/4, 100%) demonstrated focal bone bridge after treatment. No patient had diffuse physeal growth arrest; only patients with intraphyseal or transphyseal ABC involvement had focal physeal growth arrest.

CONCLUSIONS

In this series, patients undergoing percutaneous doxycycline treatment of juxtaphyseal ABCs demonstrated ABC healing and a recurrence rate of 6% at >18 months. Patients without physeal ABC involvement demonstrated no evidence of physeal growth arrest.

The Pathogenesis of Implant-Related Reactive Lesions: A Clinical, Histologic and Polarized Light Microscopy Study

BACKGROUND

Peri-implant soft tissue reactive lesions (I-RLs) may jeopardize implant success and survival. To the best of the authors' knowledge, its pathogenesis is unknown. The objective of this study is to conduct a clinicopathologic and polarized light microscopy (PLM) analysis of 14 new I-RLs and compare them with comparable tooth-associated cases (T-RLs) to better understand I-RL pathogenesis.

METHODS

Fifty-eight new cases of I-RL and T-RL were retrieved from the pathology department archives of Rambam Health Care Campus, Haifa, Israel. Retrospective analysis of histopathologic and clinical features was conducted, documented, and then compared for: 1) I-RL (n = 14), 2) peri-implant pyogenic granuloma (I-PG) (n = 5), 3) peri-implant peripheral giant cell granuloma (I-PGCG) (n = 9), 4) T-RL (n = 44), 5) tooth-associated pyogenic granuloma (T-PG) (n = 21), and 6) tooth-associated peripheral giant cell granuloma (T-PGCG) (n = 23). Presence of foreign bodies was assessed using PLM.

RESULTS

Foreign bodies were found more commonly in I-RLs (n = 13/14; 93%) when compared with T-RLs (n = 18/44; 41%), which was a statistically significant difference (P = 0.01) with an odds ratio of 7.9. Microscopically, I-PGCG was associated with: 1) lower multinucleated giant cell count (P = 0.04); 2) lower density of mesenchymal cells (P = 0.05); and 3) more diffuse, non-lobulated stromal morphology (P = 0.001). Clinically, I-RLs were found in patients who were older, and all cases were located in the posterior region: mandible (n = 12/14; 86%) and maxilla (n = 2/14; 14%).

CONCLUSIONS

In cases of implant failure, implantation of foreign bodies may play a role with subsequent development of I-PG and I-PGCG-like lesions. Clinicians should be aware of this risk so they can implement measures to minimize adverse implant outcomes.