Novel karyotypes in giant cell-rich lesions of bone

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

The highly prevalent H3F3A mutation in giant cell tumours of bone is not shared by sporadic central giant cell lesion of the jaws

OBJECTIVE

Central giant cell lesion (CGCL) and giant cell tumour (GCT) are bone lesions that share similar microscopic features. Recently, it was reported that 90% of bone GCT exhibit either p.Gly34 Trp or p.Gly34 Leu in H3F3A, one of two genes for histone H3.3 located on chromosome 1. We aimed to test whether sporadic CGCL of the jaws share the H3F3A mutations reported in GCT of other bones.

METHODS

Nine samples of CGCL of the jaws were included in the study, and mutations were assessed by direct sequencing.

RESULTS

None of the CGCL samples presented the recurrent p.Gly34 Trp or p.Gly34 Leu mutations in the H3F3A gene.

CONCLUSION

On the basis of our findings, H3F3A p.Gly34 Trp or p.Gly34 Leu mutations are not a frequent event in CGCL. If these alterations are confirmed to be exclusive of GCT, the assessment of H3F3A mutations may help in the differential diagnosis of GCT and CGCL of the jaws.

USP6-induced neoplasms: the biologic spectrum of aneurysmal bone cyst and nodular fasciitis

USP6 (also known as TRE17) is a ubiquitin-specific protease that was identified as an oncogene in transfection experiments with Ewing sarcoma DNA 2 decades ago. Until recently, little was known about USP6 function and mechanisms of oncogenic activation. The identification of USP6 fusion genes in aneurysmal bone cyst (ABC) and, more recently, in nodular fasciitis led to a better understanding of the pathogenesis of these lesions. Furthermore, the detection of USP6 genomic rearrangements or USP6 fusion genes may be used as a diagnostic tool for these lesions. In this review, we discuss the clinicopathologic features, molecular pathology, and pathogenesis of ABC and nodular fasciitis. We also discuss the possible line of differentiation of ABC and its relationship to nodular fasciitis and other lesions.

Current treatment of sacral giant cell tumour of bone: a review

Sacral giant cell tumour of bone has an insidious onset and slow growth rate, making early diagnosis difficult. The tumour has a high recurrence rate and is often fatal. Magnetic resonance imaging and computed tomography (CT), including CT-guided fine-needle biopsy, are useful for early diagnosis. Although therapy for sacral giant cell tumour often involves surgical resection and reconstruction challenges, improvements in various treatment modalities, including arterial embolization and radiotherapy, have widened the effective treatment options. The current surgical and adjuvant treatment modalities available for the management of sacral giant cell tumour are systematically reviewed and a suggested treatment algorithm is provided. En bloc excision remains the surgical procedure of choice, with functional reconstruction important in cases where the lesion is high in the sacrum. The use of adjuvant radiotherapy and chemotherapy remains controversial and should be studied further. Determination of the optimum treatment for sacral giant cell tumour will require randomized controlled trials. Early diagnosis, complete surgical resection with tumour-free margins and comprehensive treatment are important for local tumour control and improved outcome.

Solid variant of aneurysmal bone cyst of the hamate

Solid variant of aneurysmal bone cyst is a variant of aneurysmal bone cyst in which the predominant histology is that of the solid material of a cystic aneurysmal bone cyst. In this article, we present a patient with solid variant of aneurysmal bone cyst of the hamate and discuss the differential diagnosis and current treatment for this lesion.

First report of a solid variant of aneurysmal bone cyst in the os sacrum

We report on a 19-year-old woman with a rapidly growing, solid variant of aneurysmal bone cyst (solid ABC) in the right part of the lateral mass of the sacrum. On admission, the magnetic resonance imaging (MRI) scan disclosed an inhomogeneous low intensity mass right of the centre of the os sacrum with a diameter of 38 x 64 mm and a height of 56 mm on T1 and T2 weighted images. The mass showed homogenous high signal intensity on Gd-enhanced images. Computed tomography demonstrated an expansile osteolytic lesion and (99m)Tc-methylene diphosphonate bone scintigraphy revealed uniform accumulation in the lesion. The histological evaluation showed a proliferation of fibroblasts, histiocytes, chronic inflammatory cells and numerous multinucleated giant cells. Nevertheless, the cells were devoid of nuclear atypia. A cystic component was not observed. In spite of thorough curettage, the patient suffered from recurrence and severe neurological deficits. A review of the literature revealed no previous cases of solid ABC in the sacrum.

Paediatric aneurysmal bone cysts of the head and neck

Objective:

To provide an up to date review of the literature on aneurysmal bone cysts, including their diagnosis, pathology, pathophysiology, radiology and management.

Method:

Retrospective review of six cases over a 15-year period.

Results:

Six patients (age range, eight months to 17 years; mean, 9.6 years) presented with an aneurysmal bone cyst in the mandible (n = 3), maxilla (n = 2) or occipital soft tissue (n = 1). Each patient underwent primary excision, with one subsequent recurrence.

Conclusion:

Aneurysmal bone cysts are benign but locally destructive entities which may occasionally present to otolaryngologists, since they can involve the head and neck region, in particular the mandible.