Imaging and differential diagnosis of primary bone tumors and tumor-like lesions of the spine

[Translated article] Diagnostic imaging in patients with vertebral compression fractures

Vertebral compression fractures by osteoporosis (OVF) is usually a diagnostic problem and coincides on the age group of metastatic vertebral compression fractures (MVF). Although radiography is the first diagnostic technique, generally is not accurate for depicting demineralization and soft tissue lesions. Magnetic resonance (MRI) is the diagnostic choice. The most relevant signs are intravertebral fluid collection or fluid signal, other vertebral deformities without oedema and older age. Among the most relevant findings for diagnosis MVF are soft tissue mass and pedicle intensity signal asymmetries. However, reproducibility of these findings in clinical practice is moderate.

Unusual Presentation of Thoracic Chordoma with Spinal Epidural Hematoma: A Rare Case Report and PRISMA-Driven Systematic Review

A chordoma is a slow growing, locally invasive, low-grade tumor belonging to the sarcoma family. It mainly affects the sacrum and skull base. We present a case of thoracic chordoma initially presented with epidural hematoma (EDH), which is a rare clinical entity. We reported this case, and also performed a PRISMA-driven systematic review to summary the similar cases in the literature. This review includes the clinical characteristics and outcome of thoracic chordoma. Our case involves a 60-year-old male who, despite no history of trauma, presented with acute paraparesis. An epidural hematoma was identified at T6 level, leading to a surgical intervention involving T4-6 laminectomy and fixation. Six months subsequent to surgery, the patient experienced progressive lower limb weakness and spasticity. Computed tomography (CT) exhibited erosion of T6 and an associated aggressive mass. Magnetic resonance imaging (MRI) revealed a large heterogenous soft tissue mass arising from the vertebral body and right pedicle of D6, protruding in the epidural space and compressing the spinal cord focally at this level. The mass measured approximately 5 × 4 × 3.5 cm. Magnetic resonance myelography indicated a filling defect at T5-6 level, confirming the intraspinal location of the soft tissue lesion. Complete excision of the mass confirmed the diagnosis of thoracic chordoma. Postoperative follow-up demonstrated notable improvement in the lower limb spasticity and paraparesis, and the patient started adjuvant radiotherapy. This case underscores the importance of maintaining a high index of suspicion when evaluating presentations resembling EDH.

Diagnostic imaging in patients with vertebral compression fractures

Vertebral compression fractures by osteoporosis (OVF) is usually a diagnostic problem and coincides on the age group of metastatic vertebral compression fractures (MVF). Although radiography is the first diagnostic technique, generally is not accurate for depicting demineralization and soft tissue lesions. Magnetic resonance (MRI) is the diagnostic choice. The most relevant signs are Intravertebral fluid collection or fluid signal, other vertebral deformities without edema and older age. Among the most relevant findings for diagnosis MVF are soft tissue mass and pedicle intensity signal asymmetries. However, reproducibility of these findings in clinical practice is moderate.

Chondromyxoid fibroma of the lumbar facet joint: A case report

Chondromyxoid fibroma (CMF) is a rarely documented benign osseous neoplasm, particularly with respect to its incidence in the lumbar spinal region. CMF predominantly manifests in vertebral bodies, exhibiting atypical emergence in ancillary anatomical sites. The present report describes, to the best of our knowledge, the second documented instance of CMF originating from the lumbar facet joint. The present case provides an example of CMF in the lumbar facet joint precipitating spinal canal stenosis, thereby engendering neurological manifestations in the lower extremities due to neoplastic proliferation through the intervertebral foramen. The present therapeutic intervention entailed surgical excision of the neoplasm concomitant with facet joint arthrodesis, with the objective of achieving comprehensive neoplasm eradication, ameliorating the symptomatology and safeguarding the spinal structural integrity of the patient. The present study aimed to illustrate the clinical implications of this rare neoplasm, thereby elucidating the diagnostic quandaries and therapeutic complexities associated with CMF in the lumbar facet joint. In addition, the present study aimed to augment the existing knowledge for the diagnosis and clinical management of CMF.

[Imaging Findings of Spinal Metastases with Differential Diagnosis: Focusing on Solitary Spinal Lesion in Older Patients]

If a solitary spinal lesion is found in an older patient, bone metastasis can be primarily considered as the diagnosis. Bone metastasis can occur anywhere, but it mostly occurs in the vertebral body and may sometimes show typical imaging findings, presenting as a single lesion. Therefore, differentiating it from other lesions that mimic bone metastases can be challenging, potentially leading to delayed diagnosis and initiation of primary cancer treatment. This review provides an overview of imaging findings and clinical guidelines for bone metastases and discusses its differences from other diseases that can occur as solitary spinal lesions in older patients.

Vertebral Primary Bone Lesions: Review of Management Options

The assessment and treatment of vertebral primary bone lesions continue to pose a unique yet significant challenge. Indeed, there exists little in the literature in the way of compiling and overviewing the various types of vertebral lesions, which can often have complicated intervention strategies. Given the severe consequences of mismanaged vertebral bone tumors-including the extreme loss of motor function-it is clear that such an overview of spinal lesion care is needed. Thus, in the following paper, we aim to address the assessment of various vertebral primary bone lesions, outlining the relevant nonsurgical and surgical interventional methods. We describe examples of primary benign and malignant tumors, comparing and contrasting their differences. We also highlight emerging treatments and approaches for these tumors, like cryoablation and stereotactic body radiation therapy. Ultimately, we aim to emphasize the need for further guidelines in regard to correlating lesion type with proper therapy, underscoring the innate diversity of vertebral primary bone lesions in the literature.

Progressive kaposiform hemangioendothelioma and sirolimus-related severe thrombocytopenia

Kaposiform hemangioendothelioma is a locally invasive tumor and we were unable to find any previous reports of multifocal progression. Sirolimus, a mammalian target of rapamycin inhibitor, has been widely used to treat kaposiform hemangioendothelioma. Herein, we report a case of multifocal progressive kaposiform hemangioendothelioma, wherein sirolimus treatment caused severe thrombocytopenia. A 12-year-old East Asian girl presented with indurated dark-purple masses on her back. The patient had received three surgical interventions following the first appearance of the masses in 2012 and subsequent reappearances in 2014 and 2016. Kaposiform hemangioendothelioma was diagnosed based on radiological and pathological findings. Two more masses appeared in the following year. The patient was treated with oral sirolimus (2.5 mg/ m2/day) and developed grade 3 thrombocytopenia 8 days later. The patient was uneventfully relieved 5 days later after the withdrawal of sirolimus and the administration of appropriate medications. This rare case indicated that kaposiform hemangioendothelioma could be progressive with local metastatic characteristics in children. Besides, the severe sirolimus-induced complication highlights the importance of serum drug level monitoring during treatment. Physicians should be extremely cautious while treating kaposiform hemangioendothelioma patients with sirolimus.

Characterization and Treatment of Spinal Tumors

The prevalence of spinal tumors is rare in comparison to brain tumors which encompass most central nervous system tumors. Tumors of the spine can be divided into primary and metastatic tumors with the latter being the most common presentation. Primary tumors are subdivided based on their location on the spinal column and in the spinal cord into intramedullary, intradural extramedullary, and primary bone tumors. Back pain is a common presentation in spine cancer patients; however, other radicular pain may be present. Magnetic resonance imaging (MRI) is the imaging modality of choice for intradural extramedullary and intramedullary tumors. Plain radiographs are used in the initial diagnosis of primary bone tumors while Computed tomography (CT) and MRI may often be necessary for further characterization. Complete surgical resection is the treatment of choice for spinal tumors and may be curative for well circumscribed lesions. However, intralesional resection along with adjuvant radiation and chemotherapy can be indicated for patients that would experience increased morbidity from damage to nearby neurological structures caused by resection with wide margins. Even with the current treatment options, the prognosis for aggressive spinal cancer remains poor. Advances in novel treatments including molecular targeting, immunotherapy and stem cell therapy provide the potential for greater control of malignant and metastatic tumors of the spine.

Primary Bone Tumors of the Spine—Proposal for Treatment Based on a Single Centre Experience

This study reports a large single-center series of primary bone tumors of the spine (PBTs). We aimed to review the concepts for management, as this kind of tumor represents a very rare entity, and also propose a new treatment algorithm. Retrospective analysis revealed 92 patients receiving surgery for PBTs from 2007 to 2019 at our center. They were analyzed based on surgical management and the course of the disease. A total of 145 surgical procedures were performed (50 cervical, 46 thoracic, 28 lumbar, and 21 sacral). Complete tumor resection was achieved in 65%, of which 22% showed tumor recurrence during follow-up (mean time to recurrence 334 days). The five-year mortality rate was significantly lower after complete resection (3% versus 25% after subtotal resection). Most of the patients improved in their symptoms through surgery. Regarding the tumor entity, the most common PBTs were vertebral hemangiomas (20%), osteoid osteomas (15%), and chordomas (16%). The Enneking graduation system showed a good correlation with the risk of recurrence and mortality. Complete resection in PBTs increased survival rates and remains the method of choice. Thus, quality of life—especially with a higher extent of resection—should be considered.

Epithelioid hemangioendothelioma of the spine: an analysis of imaging findings

Background

Epithelioid hemangioendothelioma (EHE) is a low-grade malignant vascular neoplasm with the potential to metastasize. Primary EHE of the spine is very rare and an accurate diagnosis is crucial to treatment planning. We aim to investigate the imaging and clinical data of spinal EHE to improve the understanding of the disease.

Methods

We retrospectively analyzed the imaging manifestations and clinical data of 12 cases with pathologically confirmed spinal EHE. The imaging features analyzed included number, locations, size, border, density, signal, majority of the lesions, expansile osteolysis, residual bone trabeculae, sclerotic rim, vertebral compression, enhancement.

Results

Patients included 5 female and 7 male patients (mean age: 43.0 ± 19.6 years; range 15–73 years). Multiple lesions were noted in 1 case and single lesion was noted in 11 cases. The lesions were located in the thoracic, cervical, lumbar, and sacral vertebrae in 7, 3, 1, and 1 cases, respectively. They were centered in the vertebral body and posterior elements in 9 and 3 cases, respectively. Residual bone trabeculae, no sclerotic margin, and surrounding soft-tissue mass were noted in 11 cases, each, and mild expansile osteolysis and vertebral compression were noted in 10 and 6 cases, respectively. MRI was performed for 11 patients, all of whom showed isointensity on T1WI, hyperintensity or slight hyperintensity on T2WI, and hyperintensity on fat-suppressed T2WI. A marked enhancement pattern was noted in 10 cases.

Conclusion

Spinal EHE tend to develop in the thoracic vertebrae. EHE should be considered when residual bone trabeculae can be seen in the bone destruction area, accompanied by pathological compression fracture, no sclerotic rim, and high signal intensity for a vascular tumor on T2WI.

Fifth lumbar vertebrae solitary osteochondroma arising from the neural arch, a case report

Background

Osteochondromas are a benign outgrowth of bone and cartilage and one of the most common bone tumors that usually occur in long bones, with only 1–4% being located in the spine, more frequently in the cervical and upper dorsal region, and rarely the lumbar spine. Here, we report a case of lumbar spine (L5) osteochondroma arising from the neural arch.

Case presentation

A 30-year-old man presenting with a solid painless mass at the lower lumbar region. No neurological symptoms. Radiological examinations revealed an exophytic lesion in the fifth lumbar articular process, and the spinous process appears to be a solitary osteochondroma. Lumbar spine magnetic resonance imaging showed a bony lesion covered by a 2-mm-thick cartilaginous cap. Surgical en bloc resection of the mass was performed, and the histopathological examination confirmed the diagnosis of osteochondroma. No evidence of recurrence at the end of 4-year follow-up.

Conclusion

Osteochondromas are benign tumors rarely present in the spine; diagnosis can be made by the typical appearance of the cartilaginous cap over the mass in the magnetic resonance imaging. Surgical excision is the best management option.

Primary Tumors of the Sacrum: Imaging Findings

The diagnosis of sacral neoplasms is often delayed because they tend to remain clinically silent for a long time. Imaging is useful at all stages of managing sacral bone tumors: from the detection of the neoplasm to the long-term follow-up. Radiographs are recommended as the modality of choice to begin the imaging workup of a patient with known or suspected sacral pathology. More sensitive examinations such as computerized tomography (CT), magnetic resonance (MRI), or scintigraphy are often necessary. The morphological features of the lesions on CT and MRI help to orientate the diagnosis. Although some imaging characteristics are helpful to limit the differential diagnosis, an imaging-guided biopsy is often ultimately required to establish a specific diagnosis. Imaging is of paramount importance even in the long-term follow-up in order to assess any residual tumor when surgical resection is incomplete, to assess the efficacy of adjuvant chemotherapy and radiotherapy, and to detect recurrence.

Diagnostic Modality in Spine Disease: A Review

Spine diseases are common and exhibit several causes, including degeneration, trauma, congenital issues, and other specific factors. Most people experience a variety of symptoms of spine diseases during their lifetime that are occasionally managed with conservative or surgical treatments. Accurate diagnosis of the spine pathology is essential for the appropriate management of spine disease, and various imaging modalities can be used for the diagnosis, including radiography, computed tomography (CT), magnetic resonance imaging (MRI), and other studies such as EOS, bone scan, single photon emission CT/CT, and electrophysiologic test. Patient (or case)-specific selection of the diagnostic modality is crucial; thus, we should be aware of basic information and approaches of the diagnostic modalities. In this review, we discuss in detail, about diagnostic modalities (radiography, CT, MRI, electrophysiologic study, and others) that are widely used for spine disease.

Differentiating atypical hemangiomas and vertebral metastases: a field-of-view (FOV) and FOCUS intravoxel incoherent motion (IVIM) diffusion-weighted imaging (DWI) study

PURPOSE

Some atypical vertebral hemangiomas (VHs) may mimic metastases on routine MRI and can result in misdiagnosis and ultimately to additional imaging, biopsy and unnecessary costs. The purpose of this study is to assess the utility of intravoxel incoherent motion (IVIM) diffusion-weighted imaging (DWI) on account of field-of-view optimized and constrained undistorted single shot (FOCUS) in distinguishing atypical VHs and vertebral metastases.

METHODS

A total of 25 patients with vertebral metastases and 25 patients with atypical VHs were confirmed by clinical follow-up or pathology. IVIM-DWI imaging was performed at different b values (0, 30, 50, 100, 150, 200, 400, 600, 800, 1000 mm²/s). IVIM parameters [the true diffusion coefficient (D), pseudodiffusion coefficient (D*), standard apparent diffusion coefficient (ADC), and perfusion fraction (f)] were calculated and compared between two groups by using Student's t test. A receiver operating characteristic analysis was performed.

RESULTS

Quantitative analysis of standard ADC and D parameters showed significantly lower values in vertebral metastases when compared to atypical hemangiomas [ADC value: (0.70 ± 0.12) × 10^-3 mm²/s vs (1.14 ± 0.28) × 10^-3 mm²/s; D value: (0.47 ± 0.07) × 10^-3 mm²/s vs (0.76 ± 0.14) × 10^-3 mm²/s, all P < 0.01]. The sensitivity and specificity of D value were 93.8% and 92.3%, respectively.

CONCLUSION

The standard ADC value and D value may be used as an indicator to distinguish vertebral metastases from atypical VHs. FOCUS IVIM-derived parameters provide potential value in the quantitatively differentiating vertebral metastases from vertebral atypical hemangiomas.

Solitary vertebral metastatic glioblastoma in the absence of primary brain tumor relapse: a case report and literature review

BACKGROUND

Metastatic glioblastoma presenting as a solitary osteolytic cervical vertebral mass without primary brain tumor relapse is extremely rare with only 1 reported case in the literature. Because of its rarity, it can be easily overlooked and misdiagnosed, posing a diagnostic dilemma.

CASE PRESENTATION

A 51-year-old man with right temporal glioblastoma was initially treated by tumor resection, radiotherapy and chemotherapy. Eighteen months after surgery, he was readmitted with complaints of neck pain for 2 weeks. Follow-up magnetic resonance imaging (MRI) and fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) revealed a solitary FDG-avid osteolytic lesion in the 4th cervical vertebral body without other abnormal FDG-uptake in the body and in the absence of local recurrence at the resection cavity. Because of the sudden worsening situation and intractable neck pain, the patient underwent tumor resection. Postoperatively, the pain was obviously reduced and the situation was improved. Interestingly, the immunohistochemical findings of glial fibrillary acidic protein (GFAP) indicated the characteristic of metastatic glioblastoma, despite that the histopathological findings of Hematoxylin & Eosin (H&E) staining was suspicious of osteoclastoma. According to the clinical history, imaging findings, pathological and immunohistochemical results, a final diagnosis of solitary vertebral metastasis from glioblastoma without central nervous system (CNS) relapse was confirmed. Then, the patient received radiotherapy on spine and adjuvant chemotherapy with temozolomide. However, he died suddenly 2 months after the tumor resection, nearly 21 months after the initial diagnosis.

CONCLUSION

We emphasize that metastatic glioblastoma should be considered in the differential diagnosis of a solitary FDG-avid osteolytic vertebral mass on PET/CT. And the diagnosis of extracranial metastasis (ECM) from glioblastoma can be achieved through clinical history, imaging findings, pathological examination, and immunohistochemical staining with GFAP.

Bone up on spinal osseous lesions: a case review series

Spinal osseous neoplasms are frequently encountered and can be challenging when present as solitary lesions. Familiarity with the range of benign and malignant spinal pathology can help the radiologist formulate a comprehensive differential diagnosis. This article focuses on the spectrum of extradural spinal tumors, accounting for the majority of primary spinal tumors, by comparing the epidemiology, pathophysiology, clinical presentation, and characteristic imaging appearance of these lesions. The discussion includes the commonly encountered benign lesions, such as vertebral venous vascular malformation and enostosis, as well as malignant lesions including metastases and lymphoma. The article also includes other less-encountered primary spinal tumors such as plasmacytoma, osteoid osteoma, osteoblastoma, giant cell tumor, eosinophilic granuloma, chordoma, chondrosarcoma, osteosarcoma, Ewing’s sarcoma, and angiosarcoma. Familiarity with the characteristic imaging features can help the radiologist reach an accurate diagnosis and obviate the need for unnecessary invasive procedures such as biopsy and surgery.

Huge chondromyxoid fibroma of the right iliac wing with tremendous soft tissue extensions

This report describes a huge chondromyxoid fibroma (CMF) that developed in the right iliac crest and wing. The tumour is rare, perhaps the rarest of all bone tumours, and its occurrence in the iliac crest and wing of a 63-year-old male is extraordinarily uncommon. The patient complained of gradual onset of right groin pain over a period of more than 2 years and low back pain and tender swelling of the right gluteal region over a period of another 1 year. Conventional radiography of the lumbar spine and pelvis revealed a large osteolytic lesion of the right iliac crest and wing associated with mild levoscoliosis. MRI of the pelvis revealed a huge well-defined lesion arising from the right iliac crest and wing and extending to the right paraspinal region, false pelvis and right gluteal region and displacing rather than invading the surrounding structures. The patient underwent surgery, and the mass was totally removed. The clinical manifestations, imaging findings and surgical treatment of the lesion are discussed.

Vertebral metastases from neuroendocrine tumours: How to avoid false positives on 68Ga-DOTA-TOC PET using CT pattern analysis?

OBJECTIVES

To develop criteria to improve discrimination between vertebral metastases from neuroendocrine tumours (NETs) and benign bone lesions on PET combined with CT using DOTA-D-Phe¹-Tyr³-octreotide labelled with gallium-68 (⁶⁸Ga-DOTA-TOC).

METHODS

In 535 NET patients, ⁶⁸Ga-DOTA-TOC PET/CT examinations were reviewed retrospectively for vertebral CT lesions and/or PET foci. For each vertebral PET abnormality, appearance on CT, biological volume (BV), standardized uptake value (SUV_max) and ratios to those of reference organs were determined. All vertebral abnormalities were characterized as a metastasis, a typical vertebral haemangioma (VH) or other benign lesion.

RESULTS

In 79 patients (14.8 %), we found 107 metastases, 34 VHs and 31 other benign lesions in the spine. The optimal cut-off values to differentiate metastases from benign lesions were BV ≥0.72 cm³, SUVmax ≥2, SUVmax ratio to a reference vertebra ≥2.1, to liver ≥0.28 and to spleen ≥0.14. They corresponded to lesion-based ⁶⁸Ga-DOTA-TOC PET/CT sensitivity of 87 %, 98 %, 97 %, 99 % and 94 %, and specificity of 55 %, 100 %, 90 %, 97 %, 100 %, respectively.

CONCLUSIONS

The high sensitivity of ⁶⁸Ga-DOTA-TOC-PET/CT in detecting NET vertebral metastases was confirmed; this study showed that specificity could be improved by combining CT features and quantifying ⁶⁸Ga-DOTA-TOC uptake.

KEY POINTS

• Bone metastases in neuroendocrine tumours correlate with prognosis. • Benign bone lesions may mimic metastases on ⁶⁸ Ga-DOTA-TOC PET/CT imaging. • The specific polka-dot CT pattern may be missing in some vertebral haemangiomas. • Lesion atypical for haemangiomas can be better characterized by quantifying ⁶⁸ Ga-DOTA-TOC uptake.

Differential diagnosis of hemangiomas from spinal osteolytic metastases using 3.0 T MRI: comparison of T1-weighted imaging, chemical-shift imaging, diffusion-weighted and contrast-enhanced imaging

The retrospective study investigated accuracy of quantitative evaluation of T1-weighted imaging (T1WI) with and without fat suppression (FS), chemical-shift, diffusion-weighted imaging (DWI) and enhanced imaging at 3.0 T MRI for distinguishing spinal hemangiomas from metastases. 27 patients with 33 spinal hemangiomas (15 atypical hemangiomas) and 26 patients with 71 metastases were recruited. T1WI, FS T1WI, in- and out-phase, DWI and enhanced T1WI were acquired. Signal intensities (SIs) of lesions were obtained. Signal intensity ratios (SIRs) and enhancement ratios of lesions in enhanced imaging were assessed. Ratio of SI loss of hemangiomas or atypical hemangiomas between T1WI and FS T1WI was higher than those of metastases (p < 0.001). The accuracies of ratio of SI loss between T1WI and FS T1WI for differentiating hemangiomas and atypical hemangiomas from metastases were 96.15% and 91.86%. Ratio of SI loss between in- and out- phase could differentiate hemangiomas and atypical hemangiomas from metastases with accuracies of 74.04% and 84.88%. Cutoff values for hemangiomas in SIRs of ≤ 1.52 (early phase) and ≤ 1.38 (middle phase) yielded accuracies of 92.31% and 82.69%. Enhancement ratios of atypical hemangiomas in middle and delayed phases were higher than that of metastases. Accuracies of apparent diffusion coefficient for differentiating hemangiomas and atypical hemangiomas from metastases were 70.19% and 89.53%. T1WI with and without fat suppression could distinguish spinal hemangiomas from metastases. Quantitative assessment of chemical-shift, DWI and enhanced imaging were helpful to identification of spinal hemangiomas and metastases.

Spinal osteoid osteoma: efficacy and safety of radiofrequency ablation

OBJECTIVE

The aim of this study was to evaluate the efficacy and complications of CT-guided radiofrequency ablation (RFA) of spinal osteoid osteoma (OO).

MATERIALS AND METHODS

Between 2002 and 2012, a total of 61 patients (46 male and 15 female, mean age 26.4 ± 12.7 years) were subjected to RFA for spinal OO. The diagnosis of OO was made after a period of pain and symptoms of 20.6 ± 14.4 months. RFA was performed under conscious sedation and local analgesia. Clinical symptoms were evaluated at 3, 6, and12 months, and at the end of the time of the present investigation. Mean follow-up was 41.5 ± 7.1 months.

RESULTS

The primary efficacy of RFA, complete regression of symptoms, was obtained in 57 out of 61 patients (93.4%). Four out of 61 (6.5%) patients showed a relapse of OO (after 3 months); 2 out of 4 were subjected to a second RFA, the remaining ones were subjected to surgery. There was one complication (case of lower limb paresthesia for 30 days after the ablation) and one possible complication (a disc herniation).

CONCLUSION

CT-guided RFA is an excellent treatment for spinal OO. Our data suggest that this procedure should be considered for the first stage of therapy for this disease.

[Conventional radiological diagnosis of benign none neoplasms]

BACKGROUND

Benign bone tumors are of special clinical importance because they might be confused with malignant bone tumors.

OBJECTIVES

The aim of this article it to present the characteristics of benign bone tumors. The focus is orientated towards conventional x‑ray as the essential pillar for primary diagnosis. Consequently, the description of signal intensities of benign bone tumors in magnetic resonance images or less helpful clues like male-female ratios are deliberately omitted.

RESULTS

The classification of bone tumors introduced by Lodwick allows the identification of benign growth patterns. Growth patterns will not help, for example, in case of dedifferentiation of benign chondroid tumors towards chondrosarcomas. Therefore, each diagnosis has to incorporate the patient's clinical scenario. Furthermore, benign bone tumors might also cause aggressive growth patterns. Tumors classified as Lodwick Ic or higher should not be automatically regarded as malignant. Naturally, further clarification is mandatory for these tumors.

CONCLUSIONS

Differentiation between definitely benign bone tumors and those which need further work up is a critical diagnostic step. In the majority of cases, this is possible based on the appearance in conventional x‑ray images. In case of possibly malignant lesions, both the patient's symptoms and the x‑ray morphology have to be considered by orthopedic surgeons, pathologists, and radiologists to determine the optimal diagnostic strategy.

Aneurysmal Bone Cyst of the Cervical Spine in Children: A Review and a Focus on Available Treatment Options

OBJECTIVE

To present a series of pediatric cervical spine (CS) aneurysmal bone cysts (ABC), to review the literature, and to propose a treatment algorithm.

MATERIAL

We present a series of 4 cases of ABC and review the literature using PubMed, EMBASE, and Google scholar.

RESULTS

Only 51 cases are documented. The mean age at diagnosis is 11.5 years, and there is a small female predominance (F:M ratio=1.6). Most of ABC occurs in the upper CS (41%), are located in the posterior component (75%), and extends in 40% of the vertebral body. A single treatment modality was used in 56.9%, whereas combination of surgery with other treatment modalities was used in the rest. Of the total number of cases, 56.8% were managed with marginal resection, and instrumentation was used in 80%. Mean follow-up was 72.5 months, with the majority of patients disease free. Pain is the most common symptom present at the latest follow-up.

CONCLUSIONS

ABC of the spine is a pediatric tumor occurring rarely in the CS. Treatment options vary from simple curettage to total resection with or without instrumentation. Recurrence after surgery is highest after curettage alone. The main indications for surgery are rapid progression, despite intracystic injection, and/or the presence of neurological signs or symptoms.

Primary tumors of the spine: a review of clinical features in 438 patients

Primary spinal tumors are rare. Current knowledge on this subject is therefore limited due to the lack of study with large cohort. This study is prompted to share our data on clinical profiles of primary spinal tumors collected from a large series of patients. Clinical manifestations of 438 consecutive patients were summarized retrospectively with statistical analysis. In the spine, benign tumor is more common than malignant. The most prevalent tumor is giant cell tumor. Tumors predominately occur between the age of 18 and 59 and the risk of malignancy increases significantly after 40. Main symptoms include local pain and neurological symptoms with frequent occurrence of neurological deficits and pathological fracture. Pain is caused by tumor expansion, pathological fracture and nerve entrapment. Occurrence of neurological deficits is significantly related to patent's age and the region of involvement. Giant cell tumor is associated with the highest incidence of neurological fracture with significance. Duration of symptom is 6 months on average. The most affected region is the cervical spine, followed by the thoracic and the lumbar spine. Tumors at the sacrum and coccyx are more likely to be malignant. Malignant tumors have significantly higher incidence of involvement at multiple levels than benign tumors. This study contributes by improving our understanding of this rare clinical entity.

Positron emission tomography/computed tomography for bone tumors (Review)

The aim of the present study was to investigate positron emission tomography (PET)/computed tomography (CT) and its applications for the diagnosis and treatment of bone tumors. The advantages and disadvantages of PET/CT were also evaluated and compared with other imaging methods and the prospects of PET/CT were discussed. The PubMed, Medline, Elsevier, Wanfang and China International Knowledge Infrastructure databases were searched for studies published between 1995 and 2013, using the terms 'PET/CT', 'positron emission tomography', 'bone tumor', 'osteosarcoma', 'giant cell bone tumor' and 'Ewing sarcoma'. All the relevant information was extracted and analyzed. A total of 73 studies were selected for the final analysis. The extracted information indicated that at present, PET/CT is the imaging method that exhibits the highest sensitivity, specificity and accuracy. Although difficulties and problems remain to be solved, PET/CT is a promising non-invasive method for the diagnostic evaluation of and clinical guidance for bone tumors.

Diagnosis and treatment of low back pain in the pediatric population

Back pain in the pediatric population is a common complaint presenting to sports medicine clinics. There is a wide differential that should be considered, including mechanical, infectious, neoplastic, inflammatory, and amplified musculoskeletal pain. The history, pain quality, and examination are key components to help distinguish the etiologies of the pain and direct further evaluation. Laboratory investigations, including blood counts and inflammatory markers, can provide insight into the diagnosis. The HLA-B27 antigen can be helpful if a spondyloarthropathy is suspected. Imaging as clinically indicated typically begins with radiographs, and the use of MRI, CT, or bone scan can provide additional information. Proper diagnosis of back pain is important because prognosis and treatments are significantly different. We review the pertinent evaluation, differential diagnoses, and treatment of low back pain in the pediatric population.

Langerhans cell histiocytosis of spine: a comparative study of clinical, imaging features, and diagnosis in children, adolescents, and adults

BACKGROUND CONTEXT

Langerhans cell histiocytosis (LCH) of the spine has been well documented in the literature, but most studies concern management of the disease. No focused report on the differences in clinical and radiographic features of spinal LCH among children, adolescents, and adults exists.

PURPOSE

To review and stress the clinical and imaging differences of spinal LCH in children, adolescents, and adults to avoid false diagnosis.

STUDY DESIGN

A retrospective study of children and adults with LCH of the spine.

PATIENT SAMPLE

Consecutive patients treated at our institution.

OUTCOME MEASURES

Visual analog scale for pain, Frankel scale for neurologic status, and X-ray, computed tomography (CT) and magnetic resonance imaging (MRI) for imaging.

METHODS

Seventy-six patients with pathology-proven LCH involving the spine were treated at our institution between 1996 and 2010. Only patients with spine involvement pathologically and/or radiographically were included. Two groups were identified based on the age. Group I comprised children and adolescents (age <18 years; n=40) and Group II comprised adults (age ≥18 years; n=36). Analysis included age and gender distribution, clinical presentation, and imaging features and diagnosis. Pathologic diagnosis was performed by needle or open biopsy of the lesions.

RESULTS

Of the 76 patients, 55 were male and 21 were female (ratio of 2.62:1). Neck or back pain was the most common symptom in all patients and was the only presenting symptom in some patients. Restricted motion of spine was the most frequent symptom secondary to pain. Thirty-seven patients presented with neurologic symptoms. Adult patients were more likely to suffer neurologic deficits (p<.005). The distribution of lesions revealed predominance in the cervical spine, followed by thoracic and lumbosacral spine. Plain radiology of children and adolescents with spinal LCH usually revealed a typical vertebral plana, but the adult patients represented different severity of vertebral collapse without typical features. The images of CT scans between the two groups were similar, and all revealed lytic lesions in vertebral bodies and/or posterior elements. In Group I, lesions showed hypointense on T1-weighted images in 15 cases and isointense in 25 cases. Nineteen patients presented as intermediate to slight high signal on T2-weighted images, and the remaining patients presented as hyperintense on T2-weighted images. In Group II, lesions showed hypointense on T1-weighted images in 29 cases, isointense on T1-weighted images in seven cases, and hyperintense on T2-weighted images in 36 cases. Paraspinal soft tissue mass was detected in 28 and 23 cases in Group I and Group II, respectively. Fifteen children and adolescent patients versus 23 adult patients had epidural spinal cord compression. Oversleeve-like or dumbbell sign was observed in 21 cases in Group I but only in four cases in Group II.

CONCLUSIONS

The most common clinical manifestations of LCH of the spine were neck or back pain, followed by restricted motion of spine, neurologic symptoms, and deformity. Neurologic deficits were more frequent in adult patients. Vertebral plana is the typical imaging feature in children and adolescent patients but seldom in adults. Computed tomography is best for characterizing anatomy of the involved vertebra, and MRI is best for delineating marrow and soft tissue. The oversleeve-like sign on MRI may be a feature of spinal LCH as well as vertebra plana in children and adolescents. Needle biopsy under CT guidance should be performed before a treatment strategy is determined.

Case report: Curetting osteoid osteoma of the spine using combined video-assisted thoracoscopic surgery and navigation

BACKGROUND

A spinal osteoid osteoma is a rare benign tumor. The usual treatment involves complete curettage including the nidus. In the thoracic spine, conventional open surgical treatment usually carries relatively high surgical risks because of the close anatomic relationship to the spinal cord, nerve roots, and thoracic vessels, and pulmonary complications and postoperative pain.

CASE REPORT

We report the case of a 16-year-old girl with a symptomatic osteoid osteoma at the T9 level whose lesion was currettaged using video-assisted thoracoscopic surgery (VATS) guided by a navigation system (VATS-NAV). There were no complications and the patient had immediate relief of the characteristic pain after surgery and was asymptomatic at 5 months' followup.

LITERATURE REVIEW

Progressive advances in the technology of spinal surgery have evolved to offer greater safety and less morbidity for patients. The advent of minimally invasive surgery has expanded the indications for VATS for anterior spinal disorders. Spinal navigation systems have become useful tools allowing localization and excision of the nidus of osteoid osteomas with minimal bone resection and without radiation exposure.

CLINICAL RELEVANCE

The VATS-NAV combination in our patient allowed accurate localization and guidance for complete excision of a spinal osteoid osteoma through a minimally invasive approach without compromising spinal stability.

Image-guided percutaneous spinal biopsy

The purpose of this article is to discuss the role of imaging in the diagnosis and management of spinal disorders, with particular attention to that of image-guided percutaneous spinal biopsy. We discuss the indications, general principles, pre-procedural steps and specific techniques used for image-guided percutaneous spinal biopsy in the context of our experience and the wider literature. Percutaneous spinal biopsy is a safe and diagnostically accurate procedure when appropriately selected for further evaluation in the multidisciplinary team setting.

Malignant degeneration of a lumbar osteochondroma into a chondrosarcoma which mimicked a large retropertioneal mass

We report a case of a lumbar spinal osteochondroma that transformed into a large chondrosarcoma in a 39-year-old male who presented with an abdominal mass and back pain. This mass was also associated with a fracture of the stalk, which on cross-sectional imaging mimicked a mass of retroperitoneal origin. The diagnosis of chondrosarcoma transforming from a lumbar osteochondroma became apparent when comparison was made with previous studies.

Imaging findings of solitary spinal bony lesions and the differential diagnosis of benign and malignant lesions

OBJECTIVE

The purpose of this study was to present the MRI and CT findings of solitary spinal bone lesions (SSBLs) with the aims of aiding the differential diagnoses of malignant tumors and benign lesions, and proposing a diagnostic strategy for obscure SSBLs.

METHODS

The authors retrospectively reviewed the imaging findings of 19 patients with an obscure SSBL on MRI at our hospital from January 1994 to April 2011. The 19 patients were divided to benign groups and malignant groups according to final diagnosis. MRI and CT findings were evaluated and the results of additional work-up studies were conducted to achieve a differential diagnosis.

RESULTS

At final diagnoses, 10 (52.6%) of the 19 SSBLs were malignant tumors and 9 (47.4%) were benign lesions. The malignant tumors included 6 metastatic cancers, 3 multiple myelomas, and 1 chordoma, and the benign lesions included 4 osteomyelitis, 2 hemangiomas, 2 nonspecific chronic inflammations, and 1 giant cell tumor. No MRI characteristics examined was found to be significantly different in the benign and malignant groups. Reactive sclerotic change was observed by CT in 1 (10.0%) of the 10 malignant lesions and in 7 (77.8%) of the 9 benign lesions (p=0.005).

CONCLUSION

Approximately half of the obscure SSBLs were malignant tumors. CT and MRI findings in combination may aid the differential diagnosis of obscure SSBLs. In particular, sclerotic change on CT images was an important finding implying benign lesion. Finally, we suggest a possible diagnostic strategy for obscure SSBLs on MRI.

Chondromyxoid fibroma of the lumbar spine: case report and literature review

PURPOSE

Chondromyxoid fibroma (CMF) is a benign tumour of the bone that typically occurs in long bone metaphysis. Spinal involvement is uncommon, but more frequent in the cervical and thoracic segments. Lumbar involvement is extremely rare. We report the ninth case of lumbar CMF and the first one involving the articular process of the vertebra. A review of the literature is also intended making special emphasis on the differential diagnosis with other benign spinal tumours of the bone.

METHODS

A 21-year-old Caucasian male suffering from low back pain that increased with sports and interrupted sleep was diagnosed with a tumoural lesion in the right inferior articular process of L5.

RESULTS

Complete surgical excision of the tumour was accomplished. Histological diagnosis confirmed a CMF. The patient remains asymptomatic at 1-year follow-up.

CONCLUSION

Despite the low incidence of CMF in the lumbar spine, differential diagnosis must include this subtype of lesion among other benign tumours of the bone and cartilage. Histological diagnosis is essential in order to provide the patient with an accurate management of the pathology. Recurrence rate is to be considered even in the case of complete surgical excision. Radiotherapy administration is controversial due to suspicion of malignant transformation of the tumour.

Primary vertebral tumors: a review of epidemiologic, histological, and imaging findings, Part I: benign tumors

Primary vertebral tumors, although less common than metastases to the spine, make up a heterogeneous group of neoplasms that can pose diagnostic and treatment challenges. They affect both the adult and the pediatric population and may be benign, locally aggressive, or malignant. An understanding of typical imaging findings will aid in accurate diagnosis and help neurosurgeons appreciate anatomic subtleties that may increase their effective resection. An understanding of the histological similarities and differences between these tumors is imperative for all members of the clinical team caring for these patients. In this first review of 2 parts, we discuss the epidemiological, histological, and imaging features of the most common benign primary vertebral tumors-aneurysmal bone cyst, chondroma and enchondroma, hemangioma, osteoid osteoma, and osteoblastoma-and lesions related to eosinophilic granuloma and fibrous dysplasia. In addition, we discuss the basic management paradigms for each of these diagnoses. In combination with part II of the review, which focuses on locally aggressive and malignant tumors, this article provides a comprehensive review of primary vertebral tumors.

Eosinophilia and multifocal vertebral involvement with Hodgkin lymphoma

Patients with Hodgkin lymphoma (HL) usually present with lymphadenopathies. Osseous involvement at presentation is extremely rare. Occurrence of both eosinophilia and osseous involvement has not been reported frequently. We present an adolescent female complaining of lower back pain for 6 months, in whom, multifocal vertebral involvement and peripheral blood eosinophilia preceded the final diagnosis of HL.

Imaging appearance of primary bony tumors and pseudo-tumors of the spine

We aim to review the imaging appearance of primary bony tumors of the spine and simulating lesions. Benign bone tumors commonly appear as well-circumscribed, slow-growing lesions with a calcified or sclerotic matrix. Malignancy is often aggressive permeative lesions with bone destruction, cortical invasion and associated soft-tissue mass. CT is an excellent imaging modality for characterization of the tumor matrix, exact location, extension and osseous changes, while MR imaging is superior for evaluation of the associated soft-tissue mass, bone marrow infiltration and intraspinal extension. There is a spectrum of pseudotumors that may also involve the spine. The imaging appearance of primary spinal bone tumor in conjunction with the patient's age, gender and lesion location allows a high percentage of correct diagnosis. Imaging plays an important role in diagnosis, characterization and extension of bone tumors of the spine which will help guide therapy.

Dual-time point PET/CT with F-18 FDG for the differentiation of malignant and benign bone lesions

PURPOSE

The purpose of the present study was to evaluate whether 2-fluoro[fluorine-18]-2-deoxy-D: -glucose (F-18 FDG) positron emission tomography (PET) could differentiate malignant and benign bone lesions and whether obtaining delayed F-18 FDG PET images could improve the accuracy of the technique.

METHODS

In a prospective study, 67 patients with bone lesions detected by computed tomography (CT) or magnetic resonance imaging were included. Whole body PET/CT imaging was performed at 1 h (early) after the F-18 FDG injection and delayed imaging at 2 h post injection was performed only in the abnormal region. Semiquantitative analysis was performed using maximum standardized uptake value (SUV(max)), obtained from early and delayed images (SUV(maxE) and SUV(maxD), respectively). The retention index (RI) was calculated according to the equation: RI = (SUV(maxD) - SUV(maxE)) x 100/SUV(maxE.) Histopathology of surgical specimens and follow-up data were used as reference criteria. The SUV(maxE) and RI were compared between benign and malignant lesions.

RESULTS

The final diagnoses revealed 53 malignant bone lesions in 37 patients and 45 benign lesions in 30 patients. There were statistically significant differences in the SUV(maxE) between the malignant and benign lesions (P = 0.03). The mean SUV(maxE) was 6.8 +/- 4.7 for malignant lesions and 4.5 +/- 3.3 for benign lesions. However, a considerable overlap in the SUV(maxE) was observed between some benign and malignant tumors. With a cutoff value of 2.5 for the SUV(maxE), the sensitivity, specificity, and accuracy were 96.0%, 44.0%, and 72.4%, respectively. The positive predictive value (PPV) and negative predictive value (NPV) were 67.1% and 90.9%, respectively. There were significant differences in the RI between the malignant and benign lesions (P = 0.004). But there was overlap between the two groups. The mean RI was 7 +/- 11 for the benign lesions and 18 +/- 11 for the malignant lesions. When an RI of 10 was used as the cutoff point, the sensitivity, specificity, and accuracy were 90.6%, 76.0%, and 83.7.0%, respectively. The PPV and NPV were 81.4% and 87.1%, respectively.

CONCLUSIONS

The results of this study indicate that dual-time point F-18 FDG PET may provide more help in the differentiation of malignant tumors from benign ones.

Osteoblastoma of the Orbit

We describe a case of benign orbital tumour involving the frontal sinus and ethmoidal cells. CT findings were typical of “bone tumour of the orbit”, histological analysis yielded a diagnosis of benign osteoblastoma. A review of the literature disclosed only 13 well documented cases. We compared out radiological findings with the features described in these reports. CT patterns were similar in most cases. The lesion generally appears as a heterogeneous mass where it is possible to appreciate both high density portions and low density areas. On MRI osteoblastoma shows an iso- low signal both in T1 and in T2 sequences. Less frequently the lesion may yield a high signal in T2 images. The orbit is rarely involved by bone tumours, but all bone tumours may theoretically involve the orbit, often making it difficult to establish the right differential diagnosis by imaging. Thirteen cases are insufficient to describe general radiological criteria to improve the specificity in detection of this disease and a broader outlook is essential. For this reason we also examined the radiological signs of bone tumours involving other portions of the body. Even though many literature reports suggest CT is the landmark in bone tumour diagnosis, we think it should always be accompanied by MRI. MRI is known to overestimate local staging, but its contribution to differential diagnosis among various tumours may be decisive.

Lumbosacral osseous tumors in children

A wide variety of benign and malignant neoplasms in children involve the lumbosacral region. When a solitary lesion of the lower spine occurs, tumors or tumor-like lesions represent an important group of entities for diagnostic consideration. Diagnostic investigation should begin with a patient history, physical examination, laboratory testing, and radiography. Roentgenograms, which demonstrate bone deviations, should be used as an initial examination. The results should direct further imaging studies, such as computed tomography (CT), magnetic resonance imaging (MRI), and bone scintigraphy. CT should be the chosen modality for delineating tumoral osteoid matrix formation. MRI shows soft-tissue masses and medullary infiltration better than any other radiological modality. A multimodal radiological approach is helpful in the overall evaluation and differential diagnosis of vertebral lesions in children. Although imaging features, especially of benign lesions, may yield a high percentage of accurate diagnoses, in cases with radiological findings highly suggestive of malignancy, a specific diagnosis cannot always be made, and histopathological findings are essential to achieve the diagnosis that will guide the therapy.

A case of pulmonary vein tumor presenting as a left atrial mass

Primary cardiac tumors are extremely rare and can originate within the heart or be the result of tumor spread from other sites. We report a female patient with a pulmonary vein tumor extending into the left atrium that had a suspicious primary malignant origin with a sacral metastatic carcinoma. The patient was admitted complaining of pain in her buttock area as a result of a sacral tumor. It was believed that the sacral tumor was a metastasis from the imaging study and clinical manifestation. The primary malignant origin was evaluated. The chest CT showed a left atrium thrombus-like lesion without a pulmonary abnormality. After a transesophageal echocardiogram, the patient was diagnosed with a pulmonary vein tumor extending to the left atrium. The patient was given palliative radiotherapy for the sacral pain. Initially, the clinical impression was a metastatic sacral tumor with a thromboembolism of the left atrium. However, this patient was finally diagnosed with a pulmonary vein tumor with a left atrium extension by a transesophageal echocardiogram.