Secondary Bone Tumors Research Articles

Magnetic resonance guided focused ultrasound for treatment of bone tumors.

Magnetic resonance guided focused ultrasound (MRgFUS) is a new modality in the management of primary and secondary bone tumors. We aimed to investigate the safety, efficacy, and feasibility of using MRgFUS for the treatment of (1) benign bone tumors with the intent of complete tumor ablation, (2) primary malignant bone tumors with the intent to assess its effectiveness in causing tumor necrosis, and (3) metastatic bone disease with the intent of pain relief. Twenty-four patients with benign bone tumors, primary malignant bone tumors, and metastatic bone disease were treated with one session of MRgFUS. Contrast-enhanced (CE) magnetic resonance imaging (MRI) was carried out post-procedure to assess and quantify the area of ablation. Those with malignant primary tumors had the tumors resected 2 weeks after the treatment and the ablated areas were examined histopathologically (HPE). The other patients were followed up for 3 months to assess for the side effects and pain scores. Significant volume of ablation was noted on CE MRI after the treatment. Benign bone tumors were ablated with minimal adverse effects. Metastatic bone disease was successfully treated with significant decrease in pain scores. Ablated primary malignant tumors showed significant coagulative necrosis on MRI and the HPE showed 100% necrosis. Pain scores significantly decreased 3 months after the procedure. Only two patients had superficial skin blistering and three patients had increase in pain scores immediately after treatment. MRgFUS is effective, safe, and noninvasive procedure that can be an adjunct in the management of primary and metastatic bone tumors.

Spinal tumors in children.

Spinal tumors are rare in the pediatric population, presenting many specific peculiarities when compared to adults. We have performed a broad narrative review to describe the most common spinal tumors in children, discussing their main characteristics and management options. The authors have performed an extensive review of the peer-reviewed literature addressing the aforementioned objectives. Multimodality radiological studies (plain films, 3D computed tomography scan and magnetic resonance imaging) are necessary for proper evaluation and differential diagnosis of spinal tumors in children. In selected cases nuclear medicine imaging is used to improve the chances of a more accurate diagnosis. As a general rule, a fine needle biopsy is recommended after radiological evaluation to confirm the tumor's histology. Primary bone tumors can be divided into benign bone tumors, mostly represented by vertebral hemangiomas, osteoid osteomas, osteoblastomas, aneurismal bone cysts, and eosinophilic granulomas, and malign or aggressive tumors, such as Ewing's or osteogenic sarcomas. Secondary bone tumors (spinal metastases) comprise different tumor histologies, and treatment is mainly based on tumor's radiosensitivity. The characteristics and treatment options of the main spinal tumors are discussed in details. Spinal tumors in children are rare lesions that demand a thorough understanding of their main characteristics for their proper management. Understanding the nuances of spinal tumors in children is of paramount importance for improving outcomes and chances of cure.

Pre-operative Embolization for Bone Tumors; Single Center Experience

Objective: The purpose of this study was to report our experience with 35 patients, presenting with primary or secondary bone tumors, who underwent pre-operative transarterial embolization in our institution. Methods: Pre-operative transarterial embolizations between 2009 and 2013 were retrospectively reviewed in 35 patients (20 men and 15 women), with a mean age of 49.29 years, range 15-79 years. Medical records were reviewed to obtained patient’s data, histological diagnosis, anatomical site, post embolization complication, interval between embolization and surgery, operative procedure and operation time. Estimated blood losses (EBL) were obtained from operative notes or anesthetic notes. Results: Thirty-five patients had a total of 43 procedures in 5 years period, in which five patients underwent twice and one patient underwent four pre-operative embolizations. All 43 pre-operative embolization procedures were technically successful and underwent surgery after embolization, with a mean of 2.7 days, range 0-15 days. No patient experienced embolization associated major complication. The mean estimated blood loss was 2,915 mL (range 20-14,000 mL). Conclusion: Pre-operative transarterial embolization of both primary and secondary bone tumors was safe and effective and can help to reduce intra-operative blood loss particularly when superselective embolization was performed. Blood loss during surgery increased if the operation was not performed within 3 days after embolization due to re-canalization and angiogenesis.

Patellar resurfacing after endoprosthetic replacement for primary or secondary bone tumors.

The question of whether or not to resurface the patella during primary total knee replacement (TKR) is an enduring controversy in orthopaedic surgery (1-4). Opinion is divided—some surgeons will routinely resurface the patella, some will never resurface and the remainder will resurface or not on the basis of the appearance of the patella at operation or the location of the patient’s pain. Osteoarthritis (OA), the most common indication for TKR, is considered to be a disease of the whole joint and proponents of resurfacing suggest that the whole joint should be treated; indeed, a proportion of cases in whom patellar resurfacing is not performed will later go on to undergo secondary resurfacing. Those who do not tend to resurface the patella point to the morbidity associated with patellar resurfacing, which may predispose to patellar fracture and extensor mechanism rupture (5). On the basis of the current evidence, patellar resurfacing appears to have a small effect the overall rate of revision following surgery (probably as a result of eliminating secondary resurfacing), but has little or no effect on patient-reported outcome measures (PROMs) after TKR (2).

How to Study Basement Membrane Stiffness as a Biophysical Trigger in Prostate Cancer and Other Age-related Pathologies or Metabolic Diseases

Here we describe a protocol that can be used to study the biophysical microenvironment related to increased thickness and stiffness of the basement membrane (BM) during age-related pathologies and metabolic disorders (e.g. cancer, diabetes, microvascular disease, retinopathy, nephropathy and neuropathy). The premise of the model is non-enzymatic crosslinking of reconstituted BM (rBM) matrix by treatment with glycolaldehyde (GLA) to promote advanced glycation endproduct (AGE) generation via the Maillard reaction. Examples of laboratory techniques that can be used to confirm AGE generation, non-enzymatic crosslinking and increased stiffness in GLA treated rBM are outlined. These include preparation of native rBM (treated with phosphate-buffered saline, PBS) and stiff rBM (treated with GLA) for determination of: its AGE content by photometric analysis and immunofluorescent microscopy, its non-enzymatic crosslinking by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS PAGE) as well as confocal microscopy, and its increased stiffness using rheometry. The procedure described here can be used to increase the rigidity (elastic moduli, E) of rBM up to 3.2-fold, consistent with measurements made in healthy versus diseased human prostate tissue. To recreate the biophysical microenvironment associated with the aging and diseased prostate gland three prostate cell types were introduced on to native rBM and stiff rBM: RWPE-1, prostate epithelial cells (PECs) derived from a normal prostate gland; BPH-1, PECs derived from a prostate gland affected by benign prostatic hyperplasia (BPH); and PC3, metastatic cells derived from a secondary bone tumor originating from prostate cancer. Multiple parameters can be measured, including the size, shape and invasive characteristics of the 3D glandular acini formed by RWPE-1 and BPH-1 on native versus stiff rBM, and average cell length, migratory velocity and persistence of cell movement of 3D spheroids formed by PC3 cells under the same conditions. Cell signaling pathways and the subcellular localization of proteins can also be assessed.

How to Study Basement Membrane Stiffness as a Biophysical Trigger in Prostate Cancer and Other Age-related Pathologies or Metabolic Diseases.

Here we describe a protocol that can be used to study the biophysical microenvironment related to increased thickness and stiffness of the basement membrane (BM) during age-related pathologies and metabolic disorders (e.g. cancer, diabetes, microvascular disease, retinopathy, nephropathy and neuropathy). The premise of the model is non-enzymatic crosslinking of reconstituted BM (rBM) matrix by treatment with glycolaldehyde (GLA) to promote advanced glycation endproduct (AGE) generation via the Maillard reaction. Examples of laboratory techniques that can be used to confirm AGE generation, non-enzymatic crosslinking and increased stiffness in GLA treated rBM are outlined. These include preparation of native rBM (treated with phosphate-buffered saline, PBS) and stiff rBM (treated with GLA) for determination of: its AGE content by photometric analysis and immunofluorescent microscopy, its non-enzymatic crosslinking by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS PAGE) as well as confocal microscopy, and its increased stiffness using rheometry. The procedure described here can be used to increase the rigidity (elastic moduli, E) of rBM up to 3.2-fold, consistent with measurements made in healthy versus diseased human prostate tissue. To recreate the biophysical microenvironment associated with the aging and diseased prostate gland three prostate cell types were introduced on to native rBM and stiff rBM: RWPE-1, prostate epithelial cells (PECs) derived from a normal prostate gland; BPH-1, PECs derived from a prostate gland affected by benign prostatic hyperplasia (BPH); and PC3, metastatic cells derived from a secondary bone tumor originating from prostate cancer. Multiple parameters can be measured, including the size, shape and invasive characteristics of the 3D glandular acini formed by RWPE-1 and BPH-1 on native versus stiff rBM, and average cell length, migratory velocity and persistence of cell movement of 3D spheroids formed by PC3 cells under the same conditions. Cell signaling pathways and the subcellular localization of proteins can also be assessed.

Radiothérapie stéréotaxique des métastases osseuses vertébrales

After the liver and lungs, bones are the third most common sites of cancer metastasis. Palliative radiotherapy for secondary bone tumours helps relieve pain, improve the quality of life and reduce the risk of fractures. Stereotactic body radiotherapy can deliver high radiation doses with very tight margins, which has significant advantages when treating tumours close to the spinal cord. Strict quality control is essential as dose gradient at the edge of the spinal cord is important. Optimal schedule is not defined. A range of dose-fractionation schedules have been used. Pain relief and local control are seen in over 80%. Toxicity rates are low, although vertebral fracture may occur. Ongoing prospective studies will help clarify its role in the management of oligometastatic patients.

Primary intraosseous meningioma: an osteosclerotic bone tumour mimicking malignancy

BackgroundSclerotic tumours of the calvarial bones are rare and may be due to primary and secondary bone tumours as well as extradural tumours of meningeal origin.Case presentationWe report a case of primary intraosseous meningioma (PIM) which arose in the frontal bone of a 63 year old woman who complained of progressive pain and thickening of the right skull. Radiology showed a large osteosclerotic lesion in the right frontal bone. Histology showed an intraosseous lesion containing dense fibrous tissue in which there were scattered cells that expressed epithelial membrane antigen and progesterone receptor. The tumour was partially resected and 3 years after operation has not recurred.ConclusionsPIM is a rare tumour which needs to be distinguished from primary/secondary osteosclerotic calvarial bone tumours.

Primary Malignant Bone Tumours at the University Teaching Hospital in Lusaka Zambia

Introduction: Primary malignant bone tumours include malignancies arising primarily from bone tissue. This is opposed to secondary bone tumours in which case the neoplastic elements arise primarily from other sites within the body and secondarily spread to bone. Primary malignant bone tumours are generally considered rare. Wherever primary malignant bone tumours occur they tend to pose serious challenges in terms of diagnosis, management and morbidity and mortality. However there is a lack of organised local information demonstrating the burden of disease resulting from these tumours.Objectives: The main objective of this study was to establish the pattern of primary malignant bone tumour distribution at the UTH. The specific objectives of the study included to: Outline of the socio-demographic characteristics of patients, determining the frequency of primary malignant bone tumours at UTH and the hospital prevalence of primary malignant bone tumours including their histological distribution and the clinical presentation.Materials and Methods: A retrospective cross-sectional survey of patients who presented to The University Teaching Hospital (UTH), Lusaka, Zambia with histologically confirmed primary malignant bone tumours was conducted for the period from the 1st of January 2008 to the 31st of December 2012.Results: There were a total of hundred and fifty three (153) patients seen in total. Sixty six (43%) were females while 87 (57%) were males. The age range was 3yrs to 78yrs. The mean age was 31.6 yrs. Sixty nine percent (69%) of the patients were aged 40 years and below. The age distribution of primary malignant bone tumours showed a bimodal pattern of distribution with peaks in the second and sixth decades of life. The majority (35%) of the patients reported Lusaka Province as their domicile, while the least (2.0%) hailed from North Western Province. The highest number of patients, 39 (25.5%) was recorded in 2012 and the lowest number 20 (13%) was recorded in 2011. Based on National Cancer Registry data, from 2008 to 2011, the overall proportion of patients with primary malignant bone tumours compared to all the other cancers recorded at UTH ranged between 1.7 to 2.8%. The majority, 84 (55.3%), of the patients had osteosarcoma, followed, in descending order, by multiple myeloma 42 (27.6%), chondrosarcoma 11 (7.2%), Ewing’s sarcoma 8 (5.3%), fibrosarcoma 3 (2.0%) and lymphoma 2 (1.3%). The majority of patients (35.5%) reported pain and swelling alone as a presenting complaint while 19.8% of the patients presented with pathological fractures. The single and most commonly reported anatomical site was from multiple myeloma which has a general skeletal involvement (27%); the second most commonly involved site was the femur 23.7%, followed by the tibia 17.1%, and the humerus 7.5%.Conclusion: Notwithstanding the inconclusive nature of the information on geographic distribution of tumours, the findings in the study paralleled those reported in literature.

Third-generation percutaneous vertebral augmentation systems.

Currently, there is no general consensus about the management of osteoporotic vertebral fractures (OVF). In the past, conservative treatment for at least one month was deemed appropriate for the majority of vertebral fractures. When pain persisted after conservative treatment, it was necessary to consider surgical interventions including: vertebroplasty for vertebral fractures with less than 30% loss of height of the affected vertebral body and kyphoplasty for vertebral fractures with greater than 30% loss of height. Currently, this type of treatment is not feasible. Herein we review the characteristics and methods of operation of three of the most common percutaneous vertebral augmentation systems (PVAS) for the treatment of OVF: Vertebral Body Stenting(®) (VBS), OsseoFix(®) and Spine Jack(®). VBS is a titanium device accompanied by a hydraulic (as opposed to mechanical) working system which allows a partial and not immediate possibility to control the opening of the device. On the other hand, OsseoFix(®) and Spine Jack(®) are accompanied by a mechanical working system which allows a progressive and controlled reduction of the vertebral fracture. Another important aspect to consider is the vertebral body height recovery. OsseoFix(®) has an indirect mechanism of action: the compaction of the trabecular bone causes an increase in the vertebral body height. Unlike the Vertebral Body Stenting(®) and Spine Jack(®), the OsseoFix(®) has no direct lift mechanism. Therefore, for these characteristics and for the force that this device is able to provide. In our opinion, Spine Jack(®) is the only device also suitable for the treatment OVF, traumatic fracture (recent, old or inveterate) and primary or secondary bone tumors.

SPECT/CT IN DETECTION OF BONE METASTASES IN BREAST AND PROSTATE CANCERS

Most cancers have the ability to metastasize to the bones. Absolute leaders among them are breast and prostate cancers. Progressive growth of bone metastases causes serious metabolic disturbances in the body and loss of skeletal integrity thus resulting in the development of serious complications leading to death. The need for early detection of secondary bone cancer as well as poor images obtained by using available imaging methods contributed to the creation of multimodality SPECT/CT systems. The article discusses the use of SPECT/CT in detection of metastatic involvement of the skeleton. It describes the basic principles of SPECT/CT clinical applications. In addition, both the advantages and disadvantages of the hybrid technology are shown. The results of different studies assessing the diagnostic efficacy of SPECT/CT in the detection of secondary bone tumors are compared.

Preliminary fsLIBS study on bone tumors.

The aim of this study is to evaluate the capability of femtosecond Laser Induced Breakdown Spectroscopy (fsLIBS) to discriminate between normal and cancerous bone, with implications to femtosecond laser surgery procedures. The main advantage of using femtosecond lasers for surgery is that the same laser that is being used to ablate can also be used for a feedback system to prevent ablation of certain tissues. For bone tumor removal, this technique has the potential to reduce the number of repeat surgeries that currently must be performed due to incomplete removal of the tumor mass. In this paper, we performed fsLIBS on primary bone tumor, secondary tumor in bone, and normal bone. These tissues were excised from consenting patients and processed through the UC Davis Cancer Center Biorepository. For comparison, each tumor sample had a matched normal bone sample. fsLIBS was performed to characterize the spectral signatures of each tissue type. A minimum of 20 spectra were acquired for each sample. We did not detect significant differences between the fsLIBS spectra of secondary bone tumors and their matched normal bone samples, likely due to the heterogeneous nature of secondary bone tumors, with normal and cancerous tissue intermingling. However, we did observe an increase in the fsLIBS magnesium peak intensity relative to the calcium peak intensity for the primary bone tumor samples compared to the normal bone samples. These results show the potential of using femtosecond lasers for both ablation and a real-time feedback control system for treatment of primary bone tumors.

An 8-YEAR analysis of bone tumours in a Caribbean island

BackgroundAn epidemiologic analysis of bone tumours in Trinidad & Tobago.MethodsA retrospective analysis of primary and secondary bone tumours, site of origin and demographic data was conducted.Results63 bone tumours were analysed and included 27 primary benign (43%), 12 primary malignant (19%), 19 metastatic (30%) and 5 by contiguous spread (8%). The most common malignant primary tumour was the osteosarcoma (n = 7), originating from the femur in mostly males in the 11–20 age group. There was 1 chondrosarcoma, 2 fibrosarcomas and 2 plasmacytomas. Benign tumours consisted of 8 osteochondromas, 2 osteomas, 3 giant cell tumours, 3 bone cysts and 11 cases of fibrous dysplasia.ConclusionBone tumours are rare with a low incidence of 1.125 per 100,000 population annually and malignant tumours being even rarer at an incidence of 0.18 per 100,000 population annually. There is need for better documentation and data registries in Trinidad and Tobago.

An instrumented bone/soft tissue phantom designed to mimic HIFU treatments of bone

Clinically, HIFU exposures of bone are used to palliate pain from primary or secondary bone tumours. Such tumours weaken bone structure and render the patient susceptible to bone fracture. Ultrasound metrology for bone exposures is extremely challenging. The ultrasound beam is strongly reflected at the bone surface, with rapid surface absorption of sound entering the cortex. Pain relief is obtained when the HIFU induced temperature increase ablates the peri-osteal nerves. Standard PRF based MR thermometry, used for treatment monitoring, is inappropriate for bone. Thus, a method of determining the temperature distribution in a clinical environment is needed.

Epiphyseal Sparing and Reconstruction by Frozen Bone Autograft after Malignant Bone Tumor Resection in Children.

Limb salvage surgery has become the standard treatment for malignant primary bone tumors in the extremities. Limb salvage represents a challenge in skeletally immature patients. Several treatment options are available for limb reconstruction after tumor resection in children. We report our results using the technique of epiphyseal sparing and reconstruction with frozen autograft bone in 18 children. The mean follow-up period for the all patients included in this study is 72 ± 26 m. Eight patients remained disease-free, seven patients lived with no evidence of disease, two were alive but with disease, and one patient died of the disease. Five- and ten-year rates of survival were 94.4%. Graft survival at 5 and 10 years was 94.4%. Functional outcome using the Enneking scale was excellent in 17 patients (94.4%) and poor in one patient (5.5%). Complications include 2 nonunions, 2 fractures, 2 deep infections, 1 soft tissue recurrence, and leg length discrepancy in 7 cases. This technique is a good reconstructive choice in a child with a nonosteolytic primary or secondary bone tumor, responsive to chemotherapy, without involvement of the articular cartilage. It is a straight forward, effective, and biological technique, which affords immediate mobilization of joints and possible cryoimmune effects, with excellent long term functional outcome and less complication.

Enthesopathy of the pectoralis major tendon mimicking osteoid osteoma. A case report with an unfortunate series of events.

we present the case of an enthesopathy at the proximal humerus which was initially - due to the clinical history and a positive bone scintigraphy - regarded suspicious for metastatic breast cancer in a 50-year-old woman. after complementing radiographs and a magnetic resonance (MR) examination exhibiting a focally contrast enhancing juxtacortical osteolysis of the humerus, a metastasis seemed radiologically unlikely, but besides a traction-related periosteal reaction of the pectoralis major tendon an unusual osteoid osteoma could not unequivocally be ruled out. Although radiological follow-up was recommended the patient insisted on a surgical resection that was performed subsequently and confirmed an enthesopathy. Shortly after, she fractured her upper arm following minor trauma but is doing well after conservative treatment since then. enthesopathies presenting as unusual periosteal reactions can mimic primary and secondary bone tumors and should always be included in the differential diagnosis.

The CCN Family Proteins: Modulators of Bone Development and Novel Targets in Bone-Associated Tumors

The CCN family of proteins is composed of six extracellular matrix-associated proteins that play crucial roles in skeletal development, wound healing, fibrosis, and cancer. Members of the CCN family share four conserved cysteine-rich modular domains that trigger signal transduction in cell adhesion, migration, proliferation, differentiation, and survival through direct binding to specific integrin receptors and heparan sulfate proteoglycans. In the present review, we discuss the roles of the CCN family proteins in regulating resident cells of the bone microenvironment. In vertebrate development, the CCN family plays a critical role in osteo/chondrogenesis and vasculo/angiogenesis. These effects are regulated through signaling via integrins, bone morphogenetic protein, vascular endothelial growth factor, Wnt, and Notch via direct binding to CCN family proteins. Due to the important roles of CCN family proteins in skeletal development, abnormal expression of CCN proteins is related to the tumorigenesis of primary bone tumors such as osteosarcoma, Ewing sarcoma, and chondrosarcoma. Additionally, emerging studies have suggested that CCN proteins may affect progression of secondary metastatic bone tumors by moderating the bone microenvironment. CCN proteins could therefore serve as potential therapeutic targets for drug development against primary and metastatic bone tumors.

Nothing new under the nuclear sun: towards 80 years of theranostics in nuclear medicine

Some time in the early 2000s, the word “theranostics” (or “theragnostics”) started surfacing in the medical literature. Theranostics (from the Greek therapeuein “to treat medically” and gnosis “knowledge”) is the use of individual patient-level biological information in choosing the optimal therapy for that individual [1]. In the modern era of “personalized medicine”, theranostics is increasingly pursued in many branches of medicine in order to develop ever more effective treatment regimens. There are now many studies and reviews dedicated to theranostics, and even a journal bearing the name of this principle, detailing many different concepts on how to combine imaging and therapy using, for example, complex molecules [2] or nanotechnology [3]. However, it is rarely realized by either clinicians or scientists that nuclear medicine has been employing theranostics for nearly 80 years now. In fact, the very foundations of targeted therapy in nuclear medicine are those that are only now being adopted by other medical disciplines under the designation “theranostics”. The cornerstones of theranostics can be traced back to some of the most illustrious names among the founding fathers of nuclear medicine. Soon after Chiewitz and de Hevesy [4] described the uptake of radioactive P in the bones of rats, Erf and J.H. Lawrence (brother of the physicist Ernest O. Lawrence, who built the first cyclotron) applied this same radioisotope to patients suffering from leukaemia and polycythaemia vera [5]. Although this treatment certainly was not without success, it has since been superseded by more effective nonradioactive chemotherapy. Shortly afterwards Pecher [6] discovered that Sr accumulated in secondary bone tumours in animals, and subsequently successfully used this radioisotope to treat patients with painful bone metastases (unfortunately this work was immediately classified as secret and it took more than five decades for Sr to be registered as a therapeutic drug). These two studies are perhaps the earliest examples of diagnostic studies leading to targeted therapy of cancer using radionuclides. Around the same time the most prominent example of pure nuclear theranostic medicine emerged: the diagnosis and treatment of thyroid disorders using various isotopes of iodine. Hertz et al. in 1938 described the first study of thyroidal radioiodine uptake [7], and in 1942 Hertz and Roberts reported on the treatment of the first patients with Graves’ disease with radioiodine [8]. A short time later Seidlin et al. treated the first patient with metastatic thyroid cancer with radioiodine [9] – at the time this compoundwas so rare that radioiodinewas purified from the patient’s urine and readministered. During this therapy, additional metastases were identified using a Geiger counter and the first rudimentary dosimetry was performed. It is of course only with the benefit of hindsight that we can now say that this was the first application of theranostics in targeted molecular medicine through a specific molecular target, the sodium iodine symporter, long before any of these concepts were first described as “theranostics”. Indeed, even today it is hard to think of a single combination of targeted diagnostics and therapy that is more specific than radioiodine. F. A. Verburg (*) :A. Heinzel : F. M. Mottaghy Department of Nuclear Medicine, RWTH University Hospital Aachen, Pauwelsstrase 30, 52074 Aachen, Germany e-mail: fverburg@ukaachen.de

Painful left thigh mass

The patient lived alongside dogs and sheep on a rural Greek farm until he was a teenager. Seventeen years before presentation he emigrated to the United States. The radiographic findings of a lytic bone lesion with cortical destruction, scalloping, and periosteal reaction suggested a primary bone tumor (Fig. 1 in the case presentation). After MRI, chondrosarcoma and sarcoma with necrosis were suspected because of the regions of fluid-like signal intensity within the large soft tissue mass (Fig. 2 in the case presentation). Although echinococcal cyst was also considered, this diagnosis was incorrectly dismissed because the patient had not been on a farm for over 30 years. Therefore, the potential for disease spread and anaphylaxis were not considered prior to biopsy. Percutaneous CT-guided 14-gauge needle biopsy targeted the vastus lateralis to enable needle track resection at surgery. Aspirated fluid and cyst wall fragments were diagnostic of hydatid disease (HD) from Echinococcus granulosus. Radical resection of the soft tissue component with debridement of the femur was performed. Low power histological evaluation showed the hydatid cyst and daughter vesicles with central clear areas that had contained primarily fluid, as well as the perihydatidic adventitia (host response; Fig. 3 in the case presentation). Higher magnification demonstrated the laminated echinococcal membrane and multinucleated giant cells in the adventitia (Fig. 3 inset, in the case presentation). Three years after resection, there was local recurrence with a pathological femoral fracture. Treatment included wide excision requiring proximal femoral replacement with a megaprosthesis total hip arthroplasty. Now, 7 years later, the patient is functioning well without assistive devices and with no recurrence. On radiographs, osseous HD may mimic an aggressive primary or secondary bone tumor, bacterial osteomyelitis, or fibrous dysplasia with coarse trabeculation, sclerosis, bone expansion, erosion, cortical destruction, and osteolysis [1, 2]. MRI may demonstrate characteristic round structures, daughter vesicles, within the mother cyst that are lower signal intensity on T1-weighted images with no enhancement after contrast medium administration, a finding helpful in the diagnosis (Fig. 2 in the case presentation) [1, 2]. The younger daughter vesicles appear darker on T1-weighted images because they contain more pure fluid and fewer protoscoleces than the mother cyst [3]. While the “rim sign,” a thick dark cyst wall on T2-weighted images, is characteristic at other sites [4], it is not as specific a finding in muscle. After contrast medium administration, the perihydatidic layer typically enhances [1] (Fig. 2c in the case presentation). Hydatid disease, which occurs in endemic areas worldwide, has a well-described life cycle [5–7]. Dogs are The case presentation can be found at doi: 10.1007/s00256-013-1634-3. F. A. Sakamoto : C. S. Winalski (*) Imaging Institute, Cleveland Clinic, 9500 Euclid Avenue, A21, Cleveland, OH 44195, USA e-mail: winalsc@ccf.org

Dentine matrix protein 1 (DMP-1) is a marker of bone-forming tumours

Dentin matrix protein 1 (DMP-1) is highly expressed by osteocytes and is a non-collagenous matrix protein found in dentin and bone. In this study, we determined the expression of DMP-1 in mature and immature human bone and examined whether DMP-1 is useful in distinguishing osteoid/bone-forming tumours from other primary and secondary bone tumours. DMP-1 expression was immunohistochemically determined in paraffin sections of a wide range of benign and malignant primary bone tumours and tumour-like lesions (n = 353). DMP-1 mRNA expression was also examined in osteosarcoma and fibrosarcoma cell lines as well as bone tumour specimens (n = 5) using real-time PCR. In lamellar and woven bone, DMP-1 was expressed in the matrix around osteocyte lacunae and canaliculi; osteoblasts and other cell types in the bone were negative. Matrix staining of the osteoid and bone was seen in bone-forming tumours including osteoma, osteoid osteoma, osteoblastoma and osteosarcoma. DMP-1 staining was also seen in fibrous dysplasia, osteofibrous dysplasia and chondroblastoma and in reactive bone in solitary bone cysts and aneurysmal bone cysts. DMP-1 was not expressed in the tumour component of other bone neoplasms including Ewing sarcoma, chondrosarcoma, leiomyosarcoma, fibrosarcoma, giant cell tumour of bone and metastatic carcinoma. DMP-1 mRNA was expressed in osteosarcoma cell lines and tumour samples. DMP-1 is a matrix marker expressed around osteocytes in human woven and lamellar bone and is useful in identifying osteosarcoma and other bone-forming tumours.