Treatment of central giant cell granuloma in children with denosumab

Hypercalcemia in children induced by denosumab: a case report and an analysis of the FDA adverse event reporting system database

BACKGROUND

The potential risks of denosumab on pediatric patients have raised concerns about its safety. This article aims to analyze the adverse effects of denosumab in minors, with a specific focus on hypercalcemia.

RESEARCH DESIGN AND METHODS

A case study involving a child was analyzed. The OpenVigil 2.1 was utilized to extract adverse event data from the FAERS database, focusing on denosumab as the primary suspect drug in pediatric patients. The study also reviewed published cases of children developing hypercalcemia after discontinuing denosumab.

RESULTS

The incidence of denosumab induced hypercalcemia in individuals under 18 years old is significantly higher than the overall incidence. The signal value for hypercalcemia was higher in the male group and was highest in the adolescent group. Hypercalcemia usually appeared approximately 4 months after denosumab discontinuation. Males had a higher peak blood calcium level. Patients aged 0-11 years had a higher average peak serum calcium compared to aged 12-17 years.

CONCLUSIONS

This study highlights the risk of hypercalcemia after discontinuation of denosumab in minors, with young age and male gender identified as potential high-risk factors. These findings offer valuable safety warnings and preventative measures for the secure administration of this drug in pediatric populations.

Management of RANKL-mediated Disorders With Denosumab in Children and Adolescents: A Global Expert Guidance Document

CONTEXT

Denosumab is an effective treatment for many receptor activator of nuclear factor kappa-B ligand (RANKL)-mediated disorders but there are potential safety considerations and limited data to guide its use in children and adolescents.

OBJECTIVE

This document seeks to summarize the evidence and provide expert opinion on safe and appropriate use of denosumab in pediatric RANKL-mediated disorders.

PARTICIPANTS

Ten experts in pediatric bone and mineral medicine from 6 countries with experience in the use of denosumab participated in the creation of this document.

EVIDENCE

Data were sourced from the published literature, primarily consisting of case reports/series and review articles because of the lack of higher level evidence. Expert opinion of the authors was used substantially when no published data were available.

CONCLUSION

Denosumab is an effective treatment for RANKL-mediated disorders in children and adolescents but is often not curative and, in some cases, is best used in conjunction with surgical or other medical treatments. Careful multidisciplinary planning is required to define the goals of treatment and expert oversight needed to manage the risk of mineral abnormalities. Substantive, collaborative research efforts are needed to determine optimal treatment regimens and minimize risks.

Central giant cell granuloma: Off-label treatment with Denosumab in a patient with Noonan syndrome

This study aims to describe the utilization of Denosumabࣨ, a human monoclonal antibody against the RANK-L receptor, in a mandibular giant cell granuloma (GCG) with a significant local aggressiveness component that was unresponsive to surgical treatment. We present a case of a 19-year-old male patient diagnosed with Noonan syndrome, who presented a multifocal giant cell granuloma with aggressive behaviour resistant to surgical treatment. Due to the functional and aesthetic implications associated with a surgical procedure, a decision was made to initiate medical treatment using Denosumabࣨ. Throughout the treatment, the patient presented excellent clinical and analytical tolerance, with no reported adverse effects. Surgical intervention remains the preferred approach for GCG. Denosumabࣨ emerges as an alternative, either as neoadjuvant treatment or as definitive therapy for unresectable or resectable tumors associated with significant morbidity. It leads to size stabilization and regression of the tumour stage.

Response of Central Giant Cell Granuloma of the Jaw to Imatinib

Central giant cell granuloma of the jaw (CGCJ) can be locally aggressive and result in facial and dental deformity. A child with CGCJ was treated surgically and with denosumab with a response but life-threatening toxicity. Imatinib, a tyrosine kinase inhibitor, was prescribed based on clinical similarities between CGCJ and cherubism, for which Imatinib has been effective. Within 2 months, a computed tomographic scan showed significant ossification, which increased over the following 8 months. This case suggests that tyrosine kinase inhibitors may be an effective option, and one with limited toxicity, for CGCJ.

Central Giant Cell Reparative Granuloma (CGCRG) of the Jaw in Children Treated with Neoadjuvant Bisposphonates: Review and a Case Report

Central giant cell reparative granuloma (CGCRG) of the jaw is a neoformation localized in the mandible or in the maxillary bone and characterized by fibrous tissue, osteoclast-like giant cells and reactive bone formation. The CGCRG is a less frequent benign tumor but sometimes it is characterized by an aggressive behavior with a very rapid growth. It affects the young adults mainly and the children occasionally. Nowadays no medication therapy is approved for CGCRG in pediatric cases. We present a case of an aggressive form of a mandibular CGCRG in a 5-year child with Arnold-Chiari syndrome. This case is unique for the use of bisphosphonates (BPs) as neoadjuvant therapy in pediatrics. The therapy were administrated with the purpose of arresting the rapid growth of the tumor in order to avoid a demolitive surgery to the young patient. The child was without symptoms and presented an unusual swelling in the left mandible developed in a few weeks. The lesion was diagnosed by a CT scan and it was confirmed by a biopsy performed for histopathological assessment a few days later. The drug therapy consisted of seven cycles iv of Zoledronate associated to Calcium Gluconate. The child was closely observed through clinical and serological evaluations during the following months. About five months after the last cycle of BPs the child underwent CT scan and a conservative surgical treatment, consisted in a deep curettage, was programmed. Seven months after surgery the aesthetic profile of the patient improved and CT scan reported a significant calcic neoapposition in the area of the previous bone lesion. After more than one year from surgery, no relapse was observed. This case report demonstrates that BPs can be used safely in pediatric patients with CGCRG. Especially BPs could have a role as neoadjuvant therapy: If administrated before surgical treatment BPs avoid the necessity of resective surgery and reduce the risk of recurrence in pediatric CGCRG after conservative curettage.

Surgical Management and Denosumab for Aneurysmal Bone Cysts of the Spine in an Australian Tertiary Paediatric Centre

Aneurysmal bone cysts (ABC) are rare osteolytic, benign but often locally aggressive tumours of the long bones or vertebrae. For spinal ABC, surgical management, embolisation or sclerotherapy alone often carry high morbidity and/or high recurrence rates. Interruption of receptor activator of nuclear factor-kappa B ligand (RANKL) signalling holds promise as an effective therapeutic strategy for these tumours. We aimed to review the approach to surgical management and evaluate the efficacy and safety of denosumab for ABC of the spine in children. Retrospective review of 7 patients treated with denosumab using a standardised protocol for ABC of the spine in a tertiary paediatric centre. Surgical intervention was only conducted if there was spinal instability or significant neurological impairment. Denosumab 70 mg/m² was given 4-weekly for at least 6 months, followed by 2 doses of zoledronate 0.025 mg/kg, aiming to prevent rebound hypercalcaemia. All patients achieved stability of the spine and resolution of neurological impairment, if present. Six patients achieved metabolic remission and have ceased denosumab without recurrence to date; the other showed clinical and radiological improvement without complete metabolic remission. Three patients developed symptomatic hypercalcaemia 5-7 months after cessation of denosumab, requiring additional bisphosphonate treatment. We present our algorithm for the surgical and medical management of paediatric spinal ABC. Denosumab produced a radiological and metabolic response in all patients, with complete remission in most. Follow-up time was not long enough to evaluate the endurance of response after cessation in some patients. Incidence of rebound hypercalcaemia in this paediatric cohort was high, prompting a change to our protocol.

RANKL inhibition for giant cell lesions of the jaw: A retrospective cohort analysis

BACKGROUND

In all giant-cell-rich lesions (GCRL) occurring in bone, a common underlying excessive RANKL expression is held responsible for the osteolytic activity. Apart from giant cell tumour of bone (GCTB), systematic outcome analysis of RANKL inhibition in other GCRL is unavailable. The aim of this study is to assess the efficacy and safety of a 1-year denosumab protocol in giant cell lesions of the jaw (GCLJ).

METHODS

A retrospective cohort study was conducted compromising patients treated with a 1-year protocol of monthly subcutaneously administered 120 mg denosumab. Objective tumour response based on histology and imaging was used to calculate objective tumour response rate, progression-free survival (PFS) and time to progression. Type, severity and frequency of adverse events were recorded in a standardised way to assess safety.

RESULTS

Twenty patients, predominantly female (90%), were included. Fifty-five per cent of lesions were located in the mandible; most classified as aggressive lesions (90%). Thirty-five per cent (7/20) of cases were either recurrent after prior treatment or progressive, while on other drug treatment. Objective tumour response rate was 100% after 12 months of treatment. Median PFS was 50.4 months (95% CI 38.0-62.8) with a cumulative PFS rate of 22.6% (95% CI 1.8-43.4) at 5 years follow-up. Median time to progression was 38.4 months (95% CI 26.0-50.8). Treatment was well tolerated, and none of the patients had to interrupt therapy for toxicity.

CONCLUSION

High-dose denosumab is effective and safe in achieving a complete response in GCLJ within 12 months. The high long-term relapse rate after treatment cessation is the main obstacle for denosumab to become standard treatment for GCLJ.

Denosumab for central giant cell granuloma in an Australian tertiary paediatric centre

BACKGROUND

Central giant cell granulomas (CGCG) are rare osteolytic, benign but often locally aggressive tumours of bone. Surgical curettage may not be possible in extensive lesions and resection carries high morbidity, especially in growing children, and previous medical therapies have had variable efficacy and high recurrence rates. Interruption of receptor activator of nuclear factor-kappa B ligand (RANKL) signalling holds promise as an effective therapeutic strategy for these tumours.

AIMS

To evaluate the efficacy and safety of our protocol for denosumab treatment of CGCG in children.

METHODS

Retrospective review of 4 patients treated with denosumab using a standardised protocol for CGCG in a tertiary paediatric centre. Denosumab 70 mg/m² was given 4-weekly, followed by 2 doses of zoledronate 0.025 mg/kg, aimed at preventing rebound hypercalcaemia.

RESULTS

Treatment of CGCG resulted in metabolic remission in all patients, but recurrence, detected by positron emission tomography (PET), occurred at 6 months in three patients and 12 months in one patient. Three patients developed symptomatic hypercalcaemia 4-5 months and one patient asymptomatic hypercalcaemia 7 months after cessation of denosumab, with 3 requiring additional bisphosphonate treatment.

CONCLUSIONS

Denosumab produced a radiological and metabolic response in our patients, but metabolic recurrence occurred in all patients. PET imaging was effective for monitoring treatment response and early detection of recurrence. Incidence of rebound hypercalcaemia in this paediatric cohort was high. We present proposed changes to our protocol with the aim of producing sustained remission and preventing rebound hypercalcaemia.

Drug Treatment of Low Bone Mass and Other Bone Conditions in Pediatric Patients

Osteoporosis may affect young individuals, albeit infrequently. In childhood, bone mass increases, reaching its peak between the second and third decades; then, after a period of stability, it gradually declines. Several conditions, including genetic disorders, chronic diseases, and some medications, can have an impact on bone homeostasis. Diagnosis in young patients is based on the criteria defined by the International Society for Clinical Densitometry (ISCD), published in 2013. High risk factors should be identified and monitored. Often simple interventions aimed to eliminate the underlying cause, to minimize the negative bone effects linked to drugs, or to increase calcium and vitamin D intake can protect bone mass. However, in selected cases, pharmacological treatment should be considered. Bisphosphonates remain the main therapeutic agent for children with significant skeletal fragility and are also useful in a large number of other bone conditions. Denosumab, an anti-RANKL antibody, could become a potential alternative treatment. Clinical trials to evaluate the long-term effects and safety of denosumab in children are ongoing.

Mechanisms of acute hypercalcemia in pediatric patients following the interruption of Denosumab

PURPOSE

Denosumab is a fully human monoclonal anti-RANK-L antibody that is clinically used to counteract the bone loss induced by exacerbated osteoclast activity. Indeed, its binding to RANK-L prevents the interaction RANK-L/receptor RANK that is essential for osteoclastogenesis and bone resorbing activity. Although there are many medications available to treat bone loss diseases, including bisphosphonates, Denosumab is highly effective since it reduces the bone erosion. The use in pediatric patients is safe. However, some concerns are related to the interruption of the treatment. Indeed, in this study, we reported hypercalcemia in two pediatric patients and alterations of circulating osteoclast precursors.

METHODS

Peripheral Blood Mononuclear Cells (PBMC) were isolated from two pediatric patients with hypercalcemia after Denosumab interruption and from 10 controls. Cytofluorimetric analysis and in vitro osteoclastogenesis experiments were performed.

RESULTS

Increase of CD16^-CD14⁺CD11b⁺ cells was revealed in PBMC from patients reflecting the enhanced in vitro osteoclastogenesis.

CONCLUSION

Our data suggest that precautions must be taken when Denosumab therapy is interrupted and gradual decrease of dose and/or timing of treatment should be performed. To prevent the onset of hypercalcemia that could be in the discontinuation phase, cytofluorimetric analysis of PBMC should be performed to evaluate osteoclast precursors.

Hypercalcemia following discontinuation of denosumab therapy: A systematic review

Denosumab is a monoclonal antibody that has been approved to treat osteoporosis, skeletal metastasis, and giant cell tumor of bone in skeletally mature patients. Due to its potential adverse effects on normal bone growth, its use has not yet been approved in skeletally immature patients; however, the use of this agent in such patients with overt or dysregulated bone resorptive conditions has been explored in recent years. While most studies have proven the effectiveness of denosumab in controlling the progression of various disorders in skeletally immature patients, they have also revealed that refractory hypercalcemia often follows the discontinuation of denosumab treatment, raising a concern over the use of this agent in these patients. Thus, this study was designed to better understand the pathology of this condition through a systematic review of the published literature. Our analysis suggests that this condition has a potential male predisposition, that there is a correlation between the duration of denosumab treatment and patient age, and that this condition often occurs within 3 months after the last administration of denosumab in skeletally immature patients but is significantly less likely in adults. These results may further underscore that high bone formation and bone turnover rates are critically associated with hypercalcemia after the discontinuation of denosumab. In contrast, given that not all skeletally immature patients develop hypercalcemia, it is probable that other unidentified factors are involved in the pathology of this condition.

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Rebound hypercalcemia often follows denosumab cessation in juveniles.

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Although relatively rare, rebound hypercalcemia can occur in adults.

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Rebound hypercalcemia may have a male predisposition in juveniles.

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Treatment duration of denosumab required to trigger hypercalcemia correlates with age.

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Onset of hypercalcemia is significantly earlier in juveniles than in adults.

Medication Management of Selected Pathological Jaw Lesions

Most jaw lesions are treated surgically. Areas of abnormal proliferation or destruction in bone are commonly treated by regional curettage, excision, or resection. However, surgery is invasive and leaves a defect where the lesion was removed. Surgical trauma to adjacent healthy tissue, including vital neurovascular bundles is often unavoidable, and can be especially traumatizing to the pediatric patient. Select jaw lesions with well-studied nonsurgical pharmaceutical treatments are presented here.