[Pediatric neurosurgical treatment of aneurysmal bone cyst at the level of thoracic spine]. / Aneurysmás csontcysta gyermek-idegsebészeti megoldása a háti gerinc magasságában.

Aneurysmal bone cysts are benign but locally aggressive bone tumours, most often affecting children and young adults. In this case report, we present the clinical  picture of a 15-year-old boy with progressive, chronic back pain. An MRI of thoracic spine  confirmed a T2 cystic spinal tumour. After considering potential options surgical removal was our choice and gross total removal was achieved with T1-3 short-segment fixation. Aneurysmal bone cysts are often rapidly expanding lesions with vascular  transformation. In order to avoid irreversible damage, in addition to early diagnosis, it is necessary to carefully consider the therapeutic options, perform surgical removal and stabilization as necessary. In case of the presented patient, extensive surgical removal and short-segmentation were performed. At 18 months of follow-up, he had no complaints and was asymptomatic. Follow-up imaging studies showed no residual or recurrent tumour to date.

Large skull osteoblastoma presented as aneurysmal bone cyst (ABC).

Aneurysmal bone cysts (ABCs) are rare benign vascular bony lesions mostly encountered in young patients. These cysts can occur as primary lesions or, less frequently, secondary to other pathologies such as osteoblastomas. Skull ABCs are rare and can extend intracranially, presenting with hydrocephalus and bleeding. Here we illustrate the case of a 9-year-old male who presented with headache, nausea, and vomiting, without neurological deficit. Radiological investigations showed a soap-bubble lesion with mass effect over the right cerebellum. The patient underwent right sub-occipital craniotomy with marginal wide resection of the cystic lesion. The patient had excellent outcomes. The histopathological report was consistent with osteoblastoma with an aneurysmal bone cyst.

Aneurysmal bone cyst: Is selective arterial embolization effective as curettage and bone grafting?

INTRODUCTION: Aneurysmal bone cyst (ABC) is a lytic benign bone lesion representing about 1% of all primary bone tumors. Method to treat ABC's have developed over time. The standard of care cure for ABC has been curettage with or without bone grafting of the defect but is burdened by recurrence rates of approximately 25%-31%. Based on the assumption that ABCs usually supplied by one or more pathological feeding arteries, selective arterial embolization has been described as an adjuvant preoperative procedure to reduce intra-operative hemorrhage, and as primary treatment for lesions in difficult surgical access. In the current study, we therefore asked whether (1) a single or a repeat selective arterial embolization (SAE) for treating ABCs would produce comparable healing rates compared with curettage and bone grafting; (2) evaluated the relationship of recurrence in relation to the site of the cyst, the age, and gender of the patients; and (3) the two techniques differ in term of long-term complication. MATERIAL AND METHODS: We retrospectively reviewed 265 patients who underwent curettage and bone grafting or SAE performed at our institute from 1994 to 2018. The diagnosis of ABC was always established with percutaneous CT-guided biopsy or open biopsy. Patients were followed clinically with plain radiographs or CT scan at 3, 6, 9, and 12 months then annually in the absence of symptoms. Treatment success was determined evaluating pre- and postprocedural imaging according to Chang classification. RESULTS: Two hundred and nineteen were treated with curettage and bone grafting (curettage group), and 46 with SAE Group. Of the 219 patients treated with Curettage and bone grafting (curettage group), 165 out of 219 (75.3%) experienced bone healing, while local recurrence was observed in 54 cases (24.7%) after 12 months on average (range: 3-120 months) from surgery. After the first SAE, bone ossification was seen in 27 (58.7%), without needing any further treatment. Eleven recurred patients were treated with SAE (four patients need two while seven need three SAE to heal), and eight patients with curettage and bone grafting. Thirty-eight out of 46 (82%) patients experienced bone ossification regardless the number of SAE. The overall rate of local recurrence for all patients was 26.7%. SAE group presented a lower complication rate (6%) where two patients experienced skin necrosis, and one limb-length discrepancies (2% of all cohort). DISCUSSION: The use of SAE is an attractive option to treat ABC as it combines on one hand a lower complication rate than curettage and bone grafting, on the other it can be carried out in case of nonresectable ABCs, significantly reducing the size of viable ABC lesions, fostering bone remodeling and mineralization, and most importantly, significantly improving the patient's quality of life.

Does the preoperative neutrophil-to-lymphocyte ratio have a prognostic value in aneurysmal bone cysts?

OBJECTIVES: The aim of this study was to evaluate the prognostic value of neutrophil-to-lymphocyte ratio (NLR), lymphocyte-tomonocyte ratio (LMR), and platelet-to-lymphocyte ratio (PLR) in aneurysmal bone cysts (ABCs). PATIENTS AND METHODS: Between February 2001 and August 2019, a total of 86 patients (44 males, 42 females; mean age: 21.5±15.2 years; range, 2 to 73 years) with a histologically confirmed diagnosis of ABCs who did not receive cancer treatment previously and had a minimum follow-up period of 24 months were retrospectively analyzed. Data including age, sex, side, tumor location, pre-treatment complete blood count analysis results, preferred surgical method, follow-up period, presence of recurrence, and date of recurrence were recorded. Preoperative NLR, LMR and PLR values were calculated in all patients. RESULTS: The mean follow-up was 56.7±13.5 (range, 24 to 179) months. Forty-one (47.7%) ABCs were located in the lower extremities, 36 (41.8%) in the upper extremities, and nine (10.4%) in the pelvic girdle. A statistically significant difference was detected in the NLR values according to recurrence status (p=0.023). The PLR and LMR values were not significant for area under the curve, while NLR values were significant for recurrence. The cut-off value was determined as 2.054. Those with an NLR of ≥2.054 were found to have a 4.561-fold higher risk of recurrence than those with an NLR of <2.054 (odds ratio [OR]=4.561). CONCLUSION: Our study results suggest that NLR, which is the pre-treatment inflammatory index, is a prognostic factor in patients with ABCs. Although NLR alone is not decisive in patients with elevated NLR, it can be used to evaluate the clinical prognosis and recommend an appropriate treatment strategy.

Secondary aneurysmal bone cyst of the frontal bone with fibrous dysplasia showing rapid expansion: a case report.

A 19-year-old woman presented with swelling of the left forehead without pain. She did not have any relevant past or family history. Computed tomography showed destruction of the outer cortex of the frontal bone. A solitary mass lesion with a fluid collection was detected with magnetic resonance imaging. Because the swelling of the left forehead had enlarged rapidly with osteolytic changes, surgical removal of the lesion was performed. The lesion appeared to be enveloped in a fibrous capsule. The soft lesion was removed from the frontal bone. The outer frontal bone was absent, although the inner frontal bone was preserved. Then, the frontal bone was resected with margins from the edge of the erosion. The dura mater under the lesion was intact. A cranioplasty was performed using titanium mesh. On histological examination, the trabecular bones revealed irregular shapes and arrangements, indicating fibrous dysplasia. There was a continuous high-cell-concentration pathological lesion outside the fibrous dysplasia. There were numerous cells, such as mononuclear cells, osteoclast-like multinucleated giant cells, foam cells, and red blood cells. The osteoclast-like multinucleated giant cells and other cells did not show significant nuclear atypia. Immunostaining with H3.3G34W was negative, and the ubiquitin-specific peptidase 6/Tre-2 gene showed no rearrangements. The histopathological diagnosis was secondary aneurysmal bone cyst with fibrous dysplasia. Additional postsurgical therapy was not performed. There has been no evidence of recurrence of the lesion for two years.

Aneurysmal bone cyst of the temporal bone presenting with reversible vestibular impairment.

BACKGROUND: Aneurysmal bone cysts are expansile benign lesions associated with compressive destruction and obscure pathogenesis. The most common sites of temporal bone involvement are the petrous apex, squamous portions and mastoid. CASE REPORT: This paper reports a right temporal aneurysmal bone cyst in a 51-year-old man who presented clinically with facial palsy, and hearing loss and impaired vestibular function. Magnetic resonance imaging and computed tomography findings were consistent with a diagnosis of aneurysmal bone cyst. Inter-operative findings showed that the lesion had caused compressive damage to the internal auditory canal. Following surgical excision, the patient experienced vertigo, indicating recovery of vestibular function. Follow-up imaging revealed complete resection without clinical recurrence. CONCLUSION: To our knowledge, this is the first report of aneurysmal bone cyst invasion of the inner auditory canal. Our clinical experience indicates that vestibular nerve damage recovery is relatively uncommon. This case report will hopefully inform future studies.

The treatment of aneurysmal bone cysts.

PURPOSE OF REVIEW: Aneurysmal bone cysts are rare, locally aggressive bone tumors. Optimal treatment of ABCs is still matter of debate as therapies including sclerotherapy, selective arterial embolization and systemic treatment with denosumab are increasingly utilized, in addition to or instead of traditional curettage. The purpose of this review is to discuss current concepts and difficulties in diagnosing and treating primary ABCs, based on latest available literature. RECENT FINDINGS: In diagnostics, multiple new fusion partners of USP-6 have been described on next-generation sequencing specifically for primary ABCs. In a recent systematic review, failure rates of percutaneous injections and surgery were comparable. In a literature review, the use of denosumab seemed effective but resulted in multiple cases of severe hypercalcemia in children. SUMMARY: Accurately diagnosing primary ABC is crucial for treatment decisions. Curettage remains a valid treatment option, especially with adjuvant burring, autogenous bone grafting and phenolization. Percutaneous sclerotherapy represents a solid alternative to surgery, with polidocanol showing good results in larger studies. Systematic therapy with denosumab exhibits favorable results but should be reserved in the pediatric population for unresectable lesions, as it may result in severe hypercalcemia in children. When selecting a treatment option, localization, stability and safety should be considered.

Aneurysmal Bone Cyst of the Orbit With USP6 Gene Rearrangement.

PURPOSE: Aneurysmal bone cyst (ABC) of the orbit is a very rare tumor, occurring mostly in the pediatric population, and can result in sight threatening complications and disfigurement. This review discusses previously reported cases with a focus on evolving treatment options and molecular genetics. METHODS: We report the youngest case of an orbital ABC with a confirmed gene fusion: a 17-month-old girl, with confirmed FGFR-UPS6 (Fibroblast Growth Factor Receptor 1-ubiquitin specific peptidase 6/tre-2). A literature search for relevant publications on the topic was performed via Medline and PubMed, with the appropriate data extracted. RESULTS: Thirty-two cases of orbital aneurysmal bone cyst were identified in the literature. Presentations are varied and can include pain, proptosis, decreased vision, and extraocular motility disturbance. Typical imaging and histopathology findings are discussed, in particular the usefulness of identifying USP6 gene arrangements. Treatment modalities are reviewed including surgery, embolization, and receptor activator of nuclear factor kappa-B ligand (RANKL) inhibitors. Recurrences can occur, usually within 2 years. CONCLUSIONS: Orbital ABC is a neoplasm that presents unique diagnostic and treatment challenges. Gene rearrangements can confirm primary ABC and rule out other underlying pathology. Disfigurement and sight threatening complications can occur due to both the disease process and with treatment. Outcomes may be improved with the use of systemic therapy.

Unusual presentation of aneurysmal bone cyst with scoliosis: a case report.

BACKGROUND: Aneurysmal bone cysts are benign bone tumors that not uncommonly involves the spine. However, this involvement can cause scoliosis, albeit rarely. This report focuses on the importance of proper management for complete tumor resection to prevent recurrence and spinal deformity. CASE PRESENTATION: A 12-year-old Middle Eastern boy, with a history of T11 aneurysmal bone cyst resection and bone grafting carried out at another hospital, presented with spine deformity of 4 months' duration. The deformity was not associated with pain or neurological deficit. A whole-spine magnetic resonance imaging with contrast confirmed the recurrence of the aneurysmal bone cyst. Posterior spinal instrumentation with corpectomy of T11 was then performed, and confirmed with histopathology the recurrence of aneurysmal bone cyst. Two years post-corpectomy, deformity correction was done from T5-L4. CONCLUSION: Management of aneurysmal bone cysts requires meticulous planning and full excision to prevent recurrence, especially in the growing spine. If neglected, it can cause major spinal deformities and cord compression, which places a medical burden on the patient and family. To avoid such complications, treating aneurysmal bone cysts along with scoliosis correction can prevent deformity progression.

Aneurysmal bone cyst of the proximal femur concomitant with Graves' disease and Moyamoya disease: report of a rare case.

Aneurysmal bone cyst is a type of benign bone pathology with expansile and osteolytic features whose etiology remains unclear. Graves' disease is an autoimmune disease characterized by diffuse goiter and hyperthyroidism. Moyamoya disease is a progressive cerebral vasculopathy. It has been reported that Graves' disease and Moyamoya disease share a similar etiology involving cytokines and autoimmune and genetic factors. There are no previous reports regarding the relationship between aneurysmal bone cyst and Graves' disease. Here, we present the rare case of a 25-year-old woman with suspected aneurysmal bone cyst of the left proximal femur and a definite preoperative diagnosis of Graves' disease, in whom lesion resection combined with left total hip replacement was indicated. Biopsy confirmed the diagnosis of aneurysmal bone cyst. Three days postoperatively, the patient developed acute ischemic cerebral infarction owing to Moyamoya disease, which was subsequently confirmed. This case elucidates the potential interaction among aneurysmal bone cysts, Graves' disease, and Moyamoya disease and provides lessons regarding appropriate perioperative preparation for patients with Graves' disease who require surgery to avoid potential severe complications.

[Giant cell-containing tumors of bone and differential diagnoses]. / Riesenzell-haltige Tumoren des Knochens und Differenzialdiagnosen.

Osteoclastic giant cells represent a common cellular component of lesions arising in bone. Highlighting this morphological finding, the current WHO classification of bone tumors defines a diagnostic group comprising aneurysmal bone cyst, giant cell tumor of bone and non-ossifying fibroma, which may display morphologic similarities while being distinct with regard to molecular and biological features. Starting with these tumors - putting a focus on lesions arising in bone - this article gives a survey of other (chondrogenic and osteogenic) tumors that frequently contain osteoclastic giant cells, which may, particularly in small biopsies, enter differential diagnosis. Overlapping features with selected giant cell-containing soft tissue tumors, which may be of differential diagnostic relevance in daily routine, are discussed.

A sizeable aneurysmal bone cyst of the mandibular ramus on 15-year-old patient. Intraoral approach.

Aneurysmal bone cysts (ABCs) are benign, non-neoplastic bone lesions, which contain blood and demonstrate a destructive pattern. They rarely occur in the head and neck region, with the mandible being the most common site of craniofacial origin. They develop in the second decade of life and their etiology is obscure. ABCs can sometimes demonstrate distinct radiological features and imaging is also necessary for preoperative planning. Surgery is the mainstay of treatment. The ABC should be excised in toto and usually osteotomies and primary reconstruction are necessary. We present a case of sizeable ABC of the mandibular ramus that was excised intraorally, without the need of combined approaches or reconstruction.

Aneurysmal bone cyst and osteoblastoma after neoadjuvant denosumab: histologic spectrum and potential diagnostic pitfalls.

The use of denosumab to treat giant cell tumors of bone (GCT) and other giant cell-containing bone tumors has become more common. While the clinicopathologic features of denosumab-treated giant cell tumors of bone have been well-illustrated, descriptions of other denosumab-treated bone tumors are very limited. Surgical pathology files of two institutions and consultation files from two authors were searched for denosumab-treated aneurysmal bone cysts and denosumab-treated osteoblastomas. Clinicopathologic features were reviewed and analyzed. We identified four patients with denosumab-treated bone tumors other than GCT from our surgical pathology and consultation files, including two aneurysmal bone cysts and two osteoblastomas. All were treated with denosumab for 0.5-7.0 (median 4.5) months. Radiologically, denosumab-treated tumors showed decreased size with increased ossification and mineralization on CT and heterogeneous intermediate to hypointense signal on MRI. Histologically, denosumab-treated aneurysmal bone cyst contained thin, elongated, curvilinear, and anastomosing strands of bone with empty lacunae, while denosumab-treated osteoblastoma showed circumscribed nodules of woven bone lined by small osteoblasts. Denosumab-treated aneurysmal bone cyst and osteoblastoma showed treatment-related morphologic changes that can mimic other bone neoplasms. Their recognition requires correlation with the clinical history of denosumab use and radiologic findings.

Osteoblastoma of the Temporal Bone in a Child.

This report describes osteoblastoma of the temporal bone found on a well-child visit. The relevant clinical, radiographic, and histologic features are described. The tumor was completely resected via a transtemporal approach. The differential diagnosis for these tumors include osteoma, giant cell tumor, histiocytosis, aneurysmal bone cyst and sarcoma. Histologic findings are critical for determining the proper diagnosis.

Aneurysmal bone cyst of the head & neck: A review of reported cases in the literature.

The aneurysmal bone cyst (ABC) is a benign, blood-filled bony lesion that notoriously affects the vertebral column and long bones of the body. Rarely, ABCs can manifest in the head and neck (HNABC). The purpose of this paper is to provide a comprehensive review of existing literature on HNABC. This review includes: case reports and case series on ABCs manifesting in the head and neck region published in the English language. All cases identified via PubMed were analyzed individually. Articles were included according to specified eligibility criteria. The total number of cases analyzed were 72 (39 case reports; 33 case series). The average age at the time of HNABC diagnosis was 19.1 years (range: 0.42-62 years). The ratio of prevalence by gender affected exhibited an even 1:1 male-to-female split. CT in combination with MRI proved to be the most prevalent imaging modality utilized (37.2%). HNABC was most commonly detected in the mandible (37.1%), followed by the sinus (14.3%) and cranium (11.4%). The most frequently employed single treatment modality was surgical excision (94.1%). 94.4% of patients were alive with no evidence of disease at follow-up, while 5.6% of patients exhibited disease at follow-up. The average follow-up period was 3.59 years (range: 0.17-17.0 years). Aneurysmal bone cyst of the head and neck region is a rare condition that should be considered in the differential diagnosis of bony, vascular lesions presenting in the aforementioned locations. Since aneurysmal bone cyst of the head and neck region can present as a rapidly growing, expansive and destructive lesion, it is crucial that clinicians are aware of this entity so that patients are accurately diagnosed and treated.

Giant Cell-Rich Tumors of Bone.

The term giant cell-rich tumors of bone refers to a shared morphologic pattern in a group of different osseous lesions, that is, the abundance of osteoclastlike giant cells. Fitting with a broad spectrum of clinical presentations and biological behavior, the recent detection of characteristic molecular alterations in giant cell tumor of bone (H3-3), nonossifying fibroma (KRAS, FGFR1), giant cell granuloma of the jaws (KRAS, FGFR1, TRPV4), and aneurysmal bone cyst (USP6) have contributed significantly to the biological understanding of these morphologically related but clinically distinct lesions and their systematic classification, highlighting differences and pathogenic relationships.

Capillary Venous Malformation With Secondary Aneurysmal Bone Cyst of Temporal Bone.

Aneurysmal bone cysts (ABCs) arising from vascular malformation are extremely rare, and none have been reported in the literature in English till now. We report a very rare case of secondary ABC of left temporal bone in a 5-year-old Caucasian boy who presented with a left sudden facial palsy associated with a painless non-tender mass of the left temporo-parietal region. The computed tomography (CT) and magnetic resonance imaging (MRI) features were suggestive of ABC secondary to a capillary venous malformation, with concurrent involvement of the squamous, mastoid, and petrous portions of the temporal bone. Surgical resection was performed. On follow-up, the patient was found to be doing well.

Aneurysmal bone cyst with an unusual clinical presentation and a novel VDR-USP6 fusion.

Aneurysmal bone cyst is a benign bone neoplasm that most commonly arises from the metaphyses of long bones in the first and second decades of life. Here, we describe a case of an aneurysmal bone cyst that occurred in the distal tibial diaphysis of a 72-year-old female that was concerning for malignancy on imaging, demonstrating cortical breakthrough and soft tissue extension. Histologically, the tumor showed the characteristic morphologic features of aneurysmal bone cyst. Fluorescence in situ hybridization was positive for USP6 rearrangement, and RNA sequencing revealed a USP6 gene fusion with VDR, a novel partner that encodes the vitamin D receptor and that has not been implicated previously in human neoplasia. This case highlights the diagnostic challenges presented by aneurysmal bone cyst in elderly adults, and it expands the genetic spectrum of USP6 rearrangements.

The role of molecular diagnostics in aneurysmal and simple bone cysts - a prospective analysis of 19 lesions.

Aneurysmal (ABC) and simple bone cysts (SBC) have been traditionally distinguished by radiological and histopathological features. However, there is some radiological and histopathological overlap between ABC and SBC. ABC is characterised by USP6 fusions while, recently, NFATC2 fusions have been found in a large proportion of SBC. Identifying these fusions may assist in confirming the diagnosis of either ABC or SBC. To elaborate the potential benefit of molecular testing, we report a prospective series of 19 consecutive bone cysts with comprehensive radiological, histopathological and molecular diagnostics. Integrating radiological, histopathological and molecular findings, 11 cysts were diagnosed as SBC and 8 as ABC. Radiologically, 6 of 11 SBC and 6 of 8 ABC were diagnosed as ABC. Fibrin-like collagen deposits were identified in 8 of 11 (73%) SBC and 3 of 8 (38%) ABC. Nodular fasciitis-like areas were identified in 6 of 8 (75%) ABC and in 7 of 11 (64%) SBC. A USP6 fusion was identified in all 8 ABC, including a novel RBM5-USP6 fusion. An NFATC2 fusion was found in 7 of 11 SBC (FUS-NFATC2 fusion in 5 and EWSR1-NFATC2 in 2 cases). There is radiological and histopathological overlap between SBC and ABC in a significant proportion of cases. A diagnosis of ABC is frequently suggested radiologically in SBC, and fibrin-like deposits, thought to be specific for SBC, may be found in some ABC. Molecular testing may significantly improve diagnostic accuracy in bone cysts.