Sarcome d’Ewing agressif apparaissant comme une lésion froide sur la scintigraphie osseuse

Ewing's sarcoma classically presents as a hot spot on bone scan as a result of increased vascularity of the tumor and new bone formation.PurposeWe report and analyze an uncommon pattern of a “cold” lesion in Ewing's sarcoma on bone scan and its physiopathologic significance.Case reportA 15-year-old boy complaining of thigh pain. CT scan evocated Ewing's sarcoma or osteitis. MRI evocated chronic osteitis. Scintigraphy showed a fairly intense and heterogeneous uptake on the femoral lesion and no abnormal uptake elsewhere. Biopsy showed none pathologic pattern. Three months later, a second biopsy concluded to Ewing's sarcoma. Bone scan showed a larger lesion with peripheral intense uptake centered by enlarged “cold” area in the left femoral diaphysis and no evident bone metastasis. The patient underwent chemotherapy and surgery. Three months later, bone scan showed extensive skeletal metastasis.ConclusionEwing's sarcoma appears usually as an intense lesion on bone scan. Nevertheless, decreased radiopharmaceutical uptake or “cold” lesion may be seen in aggressive Ewing's sarcoma with lytic tumor, growth of which is very rapid and bony reaction is minimal.     

Report from Mongolia – How much do we know about the incidence of rare cases in less developed countries: a case series

Introduction

Prostate cancer is known to have a tendency to metastasize to bone. Skeletal scintigraphy can be used to show multiple lesions. Diffuse metastasis, which is not infrequent in prostate cancer, can also be suspected on the basis of a 'super scan'. However, this phenomenon in nuclear medicine has several other causes that need to be considered.

Case presentation

A patient with a history of prostate cancer presented with pleural fluid, peripheral edema and bone pain. A super scan of the bone was found which suggested diffuse skeletal metastasis of the prostate cancer but the patient also had a prostate specific antigen level which was not compatible with this diagnosis. Further investigations revealed the paraneoplastic phenomenon of hypertrophic osteoarthropathy, related to an incurable carcinoma of the lung, to be the cause of the super scan.

Conclusion

A super scan is characterized by a high bone to soft tissue ratio on skeletal scintigraphy, with a uniform symmetrical increase in bone uptake and diminished to absent renal visualization ('absent kidney sign'). It can be seen in a variety of diseases in which there is a diffusely increased bone turnover. Diffuse skeletal metastasis of a well-differentiated prostate carcinoma is unlikely to be the cause of a super scan when the prostate specific antigen level is not elevated. This is the first report of a super scan due to pulmonary hypertrophic osteoarthropathy which can be seen in lung carcinoma and other pulmonary diseases.     

Aspects des complications ostéo-articulaires de la maladie de Gaucher de type 1 en scintigraphie osseuse planaire (infection exclue) : à propos d’un cas

Type 1 Gaucher disease is an autosomal recessive inheritance lysosome storage disorder, corresponding to an inherited deficiency of glucocerebrosidase. Bone complications are frequently revealing and constitute the main source of morbidity and disability. They can appear on the acute (osseous infarction, acute osteomyelitis) or chronic mode (bone modelling disorders, osteopenia, osteonecrosis, chronic osteomyelitis). The aim of our work is to evaluate the contribution of the 99mTc labeled diphosphonates bone scan in the case of a 28-year-old patient, followed up for type 1 Gaucher disease and presenting for 2 months knees and pelvis inflammatory pain with functional impotence. X-ray had shown a stage IV aseptic osteonecrosis of the right femoral head. The bone scan found other osteo-articular lesions of the left hip, knees and right tibia related to Gaucher disease with a high likelihood. Bone scan is a very sensitive procedure in the early diagnosis and in the follow-up of bone complications of type 1 Gaucher disease. Bone scan allows to clinically silent lesions on the whole skeleton.     

Oesophageal carcinoma demonstrated by whole-body nuclear magnetic resonance imaging.

The quality of the images produced by nuclear magnetic resonance (NMR) imaging has steadily improved over the past five years. Images of the head, thorax, and abdomen have clearly shown the normal anatomy. A clinical trial of NMR imaging has therefore been started in Aberdeen to assess its diagnostic accuracy and compare it with conventional radiography and other imaging technique. The first patient examined by whole-body NMR imaging had carcinoma of the oesophagus diagnosed on barium meal examination. A technetium-99m-sulphur colloid liver scan also showed hepatic metastases. NMR imaging showed a large tumour in the lower third of the oesophagus, and areas of increased proton spin-lattice relaxation time (T1) on a section through the liver corresponded with the metastases shown on the radionuclide scan. Increased areas of T1 were present in some vertebrae, and a technetium-99m bone scan confirmed the presence of bone metastases. The NMR images in this patient compared well with the images from other techniques. The continuing clinical trial may show that NMR is an accurate diagnostic aid which will complement existing techniques for diagnosing intrathoracic and intra-abdominal conditions.     

Skeletal Scintigraphy

Skeletal scintigraphy, using phosphates or diphosphonates labeled with technetium 99m, is a sensitive method of detecting bone abnormalities. The most important and most frequent role of bone scanning is evaluating the skeletal areas in patients who have a primary cancer, especially a malignant condition that has a tendency to spread to bone areas. The bone scan is superior to bone radiographs in diagnosing these abnormalities; 15 percent to 25 percent of patients with breast, prostate or lung cancer, who have normal roentgenograms, also have abnormal scintigrams due to metastases. The majority of bone metastases appear as hot spots on the scan and are easily recognized. The incidence of abnormal bone scans in patients with early stages (I and II) of breast cancer varies from 6 percent to 26 percent, but almost invariably those patients with scan abnormalities have a poor prognosis and should be considered for additional therapies. Progression or regression of bony lesions can be defined through scanning, and abnormal areas can be identified for biopsy. The incidence of metastases in solitary scan lesions in patients with known primary tumors varies from 20 percent to 64 percent. Bone scintigraphy shows positive uptake in 95 percent of cases with acute osteomyelitis. Stress fractures and trauma suspected in battered babies can be diagnosed by scanning before there is radiological evidence. The procedure is free from acute or long-term side effects and, except in cases of very young patients, sedation is seldom necessary.Although the test is sensitive, it is not specific and therefore it is difficult to overemphasize the importance of clinical, radiographic, biochemical and scanning correlation in each patient.     

Early experience with the Autophor prosthesis using a posterior approach

Twenty-eight Autophor hip prostheses have been implanted in 25 patients, using primarily a posterior approach. Complications have included two dislocations and two femoral shaft fractures. One dislocation required reoperation. The shaft fractures healed in three months with bone grafting and cerclage wiring. There were no infections and no cases of loosening or component failure. Radiological follow-up including bone scan suggests implant boney stabilization at six months. Our early experience suggests that this implant is quite successful, especially in the young patient and the patient with significant loss of bone stock from protrusio or revision surgery.     

Diagnostics différentiels d’une lésion de la mandibule chez un patient aux antécédents de cancer ORL localement avancé

Eighteen months after completion of a radiochemotherapy treatment for a T4 tonsil cancer, a patient presented with a piece of bone coming out through a submandibular fistula and increasing pain. A CT scan, a bone scintigraphy and an 18-fluorodeoxyglucose positron-emission tomography were performed. Both diagnoses of osteoradionecrosis and tumor recurrence were suspected and then confirmed after mandibulectomy.     

Fixations extra-osseuses inhabituelles de diphosphonates technétiés dans un cas de cancer bronchique

Visceral uptake of radiobiphosphonates on bone scan is infrequent. A 53-year-old man, with untreated left lung cancer was referred to our department for a bone scan. The bone scan showed a bone metastasis at the right humeral shaft, and uncommon visceral uptake throughout the gastric wall, the liver and the right lung parenchyma. The serum biochemistry revealed a malignant hypercalcemia. Thus, the incidental observation of metastatic calcifications on bone scintigraphy should alert the physician, and lead to an etiological investigation to search an unknown calcium metabolism disturbances requiring emergency treatment.     

Fixation extraosseuse du radiotraceur lors de la réalisation d’une scintigraphie du squelette chez un patient atteint de bêta-thalassémie : à propos d’un cas

Red blood cell transfusion, main therapeutic modality of beta-thalassemia, leads to iron overload which may perturb several metabolic ways. The aim of this paper is to illustrate the uptake abnormalities observed on bone scan of thalassemic patients and to discuss mechanisms of extraosseous accumulation of the radiopharmaceutical in this pathology. We report a 16-year-old child suffering from beta-thalassemia major undergoing transfusion therapy. A bone scan was indicated to look for osseous infection. This study revealed a little skeletal uptake and abnormal liver, splenic and renal accumulation. A repeat bone scan, performed three weeks later showed a better skeletal uptake which enabled the discovery of focal abnormalities and made the diagnostic easier. The effect of iron overload on radiopharmaceuticals's uptake in bone scan is known since 1975. Dissociation of ^99mTc from the carrier ligand due to the presence of iron excess seems the most plausible hypothesis. Free ^99mTc can be bound to other tissular substrates which can explain extraosseous uptake. The normally available pool for bone is reduced and then the skeletal uptake decreased. This report limits considerably the sensitivity of the bone scan. A well-led iron chelation and eventually the use of diuretic drug may guarantee a better quality of bone scan images.     

La maladie d’Erdheim-Chester : à propos d’un cas

IntroductionErdheim-Chester disease (ECD) is a rare form of non-Langerhans histiocytosis of which prevalence is difficult to estimate. To date, 178 cases have been published. Its pathophysiology is still unknown. It is characterized by an infiltration of foamy histiocytes within several organs, mainly bone, retroperitoneum, lung, heart, brain and retro-orbital tissue.ObservationWe present the case of ECD in a 62-year-old woman with neurological symptoms, retro-orbital and osseous involvement. Diagnosis was made through an anatomopathological examination of the brain biopsy. A Tc^99m-HDP bone scan revealed a bilateral and symmetric increased uptake of diaphyses and metaphyses of the long bones and a focal increased uptake of the skull. The axial skeleton is spared. The evolution of this patient was marked by recurrences of cerebral localizations and by worsening of neurological deficits. The patient was treated by corticosteroids.Discussion and conclusionErdheim-Chester is a rare non-Langerhans histiocytosis showing characteristic radiological and histological features. Extraskeletal manifestations can occur in almost all organs, leading to a poor prognosis. The diagnosis requires biopsy with histologic confirmation of an extraosseous site. Because clinical bone symptoms can be mild or absent, bone scan may be valuable, as it discloses all sites of bone affected in one diagnostic procedure.     

Apport de la fusion d’images tomoscintigraphiques avec la tomodensitométrie X ou l’imagerie par résonance magnétique en pathologie osseuse : expérience du service de médecine nucléaire de Sfax

The aim of our study was to assess the contribution of image fusion of SPECT combined with computed tomography (SPECT-CT) or magnetic resonance imaging (SPECT-MRI) in our daily practice of bone scintigraphy. Seventeen patients underwent a SPECT image fusion, SPECT-CT or MRI in addition to conventional bone scintigraphy. These acquisitions are made separately with images stored in DICOM format. The fusion was operated after a manual coregistration of the images. Results show that in 35.29% of cases, the image fusion allowed to pinpoint the exact location of increased uptake seen on the whole body scan and/or on static images. In 35.29% of cases, the fusion has confirmed a diagnosis doubtful in planar imaging. In five patients, representing 29.41% of cases, the fusion has corrected a diagnosis. In one patient (5.88% of cases), the fusion has eliminated a false positive related to increased uptake visualized on the whole body scan. In two patients (11.11% of cases), the fusion has eliminated false negative of bone scan in one case and of MRI in the other case. Finally, in nine patients (50% of cases), the fusion has influenced the therapeutic management.     

Bilan scintigraphique osseux d’une hypercondylie unilatérale

A 10-year-old girl with unilateral condylar hyperplasia was referred to our department for a bone scan. We describe the role of the bone scan in this condition. Unilateral condylar hyperplasia is a rare disease of the mandibular condyle cartilage growth leading to facial deformity. Bone scan demonstrates the active or inactive nature of condylar hyperplasia and orients therapy. A planar bone scan completed by single-photon emission computed tomography (SPECT) combined with CT was performed. Increased uptake of the left mandibular condyle, particularly well demonstrated on SPECT images, was seen. This was confirmed by relative quantification and helped decision making to surgical treatment.     

Incorporating tissue anisotropy and heterogeneity in finite element models of trabecular bone altered predicted local stress distributions

Trabecular bone is composed of organized mineralized collagen fibrils, which results in heterogeneous and anisotropic mechanical properties at the tissue level. Recently, biomechanical models computing stresses and strains in trabecular bone have indicated a significant effect of tissue heterogeneity on predicted stresses and strains. However, the effect of the tissue-level mechanical anisotropy on the trabecular bone biomechanical response is unknown. Here, a computational method was established to automatically impose physiologically relevant orientation inherent in trabecular bone tissue on a trabecular bone microscale finite element model. Spatially varying tissue-level anisotropic elastic properties were then applied according to the bone mineral density and the local tissue orientation. The model was used to test the hypothesis that anisotropy in both homogeneous and heterogeneous models alters the predicted distribution of stress invariants. Linear elastic finite element computations were performed on a 3 mm cube model isolated from a microcomputed tomography scan of human trabecular bone from the distal femur. Hydrostatic stress and von Mises equivalent stress were recorded at every element, and the distributions of these values were analyzed. Anisotropy reduced the range of hydrostatic stress in both tension and compression more strongly than the associated increase in von Mises equivalent stress. The effect of anisotropy was independent of the spatial redistribution high compressive stresses due to tissue elastic heterogeneity. Tissue anisotropy and heterogeneity are likely important mechanisms to protect bone from failure and should be included for stress analyses in trabecular bone.     

Radiographic changes in alveolar bone height on overdenture abutments: a longitudinal study

Objective: Stabilisation of partial dentures is an important part of prosthodontic treatment, particularly in patients with an excessive reduction in alveolar bone supporting their abutment teeth. In these cases, overdenture prostheses are one possible treatment choice. Background: The aim of this study was to evaluate the effects of overdentures on the condition of alveolar bone of the remaining teeth, and to evaluate the overdenture concept in the prosthetic treatment of partially edentulous patients. Materials and methods: The investigation was conducted on 22 patients during observation periods of 6 and 10 years. After preparation, all abutment teeth were provided with either amalgam restorations or gold copings. An overdenture in the lower jaw was fabricated for every patient. A special film holder was used to repeat the X‐ray procedure in every patient in the same manner. The radiographs were evaluated using the grid scale. The alveolar bone level of all remaining teeth was evaluated on dental films by measuring the distance between the root apex and coronal border of the alveolar bone. Results: A statistically significant difference (p < 0.01) was calculated 6 years after delivery stage between distal alveolar bone levels of experimental abutments under overdentures and the remaining teeth of the control group. Alveolar bone of abutment teeth was considerably preserved, particularly in seven patients observed 10 years after provision of their dentures. Conclusion: Within the limitation of this study, the validity of the overdenture treatment in partially edentulous patients is concluded. Good oral hygiene was crucial for the success of treatment with overdentures.     

Potential for improvement in clinical decision-making: tumor imaging with in-111 labeled liposomes results of a phase ii-iii study

Abstract

Liposome scanning using In- 111 labeled VS102 liposomes (VesCan^R) has previously been shown to image a wide variety of common human tumors, probably related to tumor neovascular capIIIary fenestrations and binding of liposomes to tumor cells. We further tested In-III VS102 liposomes in a Phase II trial (27 patients) and a Phase III trial (38 patients). The sensitivity for detecting tumors in primary sites was 82% and in metastatic sites was 65% at the recommended lipid dose of 100 mg. There was 1 false positive scan (specificity 98%). Tumors which have been imaged include carcinomas of the breast, lung, head-neck, prostate, colon, ovary, cervix, thyroid, kidney, testes, melanoma, sarcoma and lymphoma. Sites imaged have included soft tissue, breast, mediastinum, bone, lung, lymph node, liver and pelvis. We also describe five patients in whom a In-111 liposome scan was performed in addition to standard tests, and in whom therapy plans were changed by use of liposome scan results. In two instances, no therapy would have been given without In-III liposome scan, but chemotherapy or radiotherapy were used based on liposome scan results and confirmatory tests. In one patient, surgery would have been used in the absence of In-III liposome scans, versus radiotherapy with In-III liposome scan results. In two other patients, palliative radiotherapy or chemotherapy would have been given without In-111 liposome scan. One of the patients would have required further therapy and the other needed curative surgery after liposome scan evaluation. These results suggest In-111 liposome scans may be useful to complement standard diagnostic tests in cancer patient management.     

Apports de l’imagerie hybride TEMP/TDM dans le descellement aseptique de prothèse de hanche

Hip prosthesis loosening detection is a common indication for bone scan, however, the diagnosis can be difficult to confirm based solely on bone scan information which have a low specificity. The development of bone SPECT/CT hybrid imaging allows the correlation of two complementary modalities to palliate the low sensitivity of CT caused by metallic artefacts and the moderate specificity of bone scan. It becomes a necessity for nuclear medicine physicians to master the bases of pathological hip prosthesis radiological semiology. We propose in this review article to recall the physiopathology of prosthesis loosening then we will describe the radiological and scintigraphic characteristics of hip prosthesis loosening as well as its differential diagnoses and the benefits of other imaging modalities.     

Fixations extra-osseuses du Tc MDP dans le cas d’un cancer du sein métastatique à l’os

Aim

To report and discuss an unusual visceral uptake on bone scan in a case of breast cancer with bone metastases.

Patient and methods

A 40-year-old woman, with untreated bilateral breast cancer was referred to our department for a bone scan.

Results

The bone scan evidenced multiple metastases over the axial skeleton. Uncommonly, visceral uptake was noted associating diffuse bilateral lung uptake and intense myocardium, stomach and kidneys uptakes. Serum calcium level was high: 4.08 mmol/L (normal: 2.38–2.70 mmol/L).

Conclusion

The incidental observation of metastasic calcifications on bone scan is often related to severe hypercalcemia. Such pattern should alert the physician on the existence and the severity of calcium metabolism disturbances that had not been suggested before.     

Role of liver scanning in the preoperative evaluation of patients with cancer

Liver scan characteristics and liver function tests of 72 patients with proved hepatic malignancy (54 metastatic, 18 primary) were evaluated. Well-defined focal defects were observed in 83% of patients with metastatic and 77% of patients with primary liver carcinoma. In 10% of the patients with metastatic liver disease the distribution of radioactivity was normal. Four or more biochemical liver function tests were normal in 33% of metastatic and 29% of primary liver cancer patients. Hepatic enlargement was present in the scan in 94% of the patients with liver metastases; however, data obtained from 104 necropsies of patients with hepatic metastases showed that only 46% had hepatomegaly. We recommend, therefore, that a liver scan should be performed before major tumour surgery in every patient with known malignancy regardless of normal liver size or normal liver function tests.     

Therapy with Zoledronic Acid, 5 Mg,for a Patient with Paget Disease of Bone

ObjectiveTo describe the effects of an infusion of zoledronic acid in a patient with Paget disease of bone (PD) who had been treated unsuccessfully with several other bisphosphonates.MethodsThe patient’s treatment history is described, and his response to various bisphosphonates, including zoledronic acid, is discussed.ResultsThe patient was a 61-year-old man when a diagnosis of PD was made on the basis of an elevated serum alkaline phosphatase (ALP) level of 391 U/L (reference range, 45 to 135). Pagetic bone changes were noted on bone scan and x-ray examinations. Treatment with etidronate had no effect on ALP levels. This intervention was followed by 2 courses of intravenous therapy with pamidronate, which decreased ALP levels by 57% and 55% without inducing a remission. Subsequent oral treatment with alendronate and then risedronate yielded unsustained biochemical remissions of 6 months each. Most recently, therapy with an infusion of 5 mg of zoledronic acid induced a remission that is thus far 20 months in duration. With this therapy, the patient has experienced no side effects, and he has noted a decrease in bone pain.ConclusionThis case study shows that a patient with PD who received successive treatments with several bisphosphonates with inadequate responses or only brief remissions was more effectively treated with a single 5-mg infusion of zoledronic acid. This patient’s therapeutic responses illustrate the relative efficacy of available bisphosphonates and the potential for longer-lasting remissions with zoledronic acid in patients with PD. (Endocr Pract. 2008;14:607-610)     

Variations in mineralization affect the stress and strain distributions in cortical and trabecular bone

The mechanical properties of bone depend largely on its degree and distribution of mineralization. The present study analyzes the effect of an inhomogeneous distribution of mineralization on the stress and strain distributions in the human mandibular condyle during static clenching. A condyle was scanned with a micro-CT scanner to create a finite element model. For every voxel the degree of mineralization (DMB) was determined from the micro-CT scan. The Young's moduli of the elements were calculated from the DMB using constant, linear, and cubic relations, respectively. Stresses, strains, and displacements in cortical and trabecular bone, as well as the condylar deformation (extension along the antero-posterion axis) and compliance were compared. Over 90% of the bone mineral was located in the cortical bone. The DMB showed large variations in both cortical bone (mean: 884, SD: 111 mg/cm(3)) and trabecular bone (mean: 738, SD: 101 mg/cm(3)). Variations of the stresses and the strains were small in cortical bone, but large in trabecular bone. In the cortical bone an inhomogeneous mineral distribution increased the stresses and the strains. In the trabecular bone, however, it decreased the stresses and increased the strains. Furthermore, the condylar compliance remained relatively constant, but the condylar deformation doubled. It was concluded that neglect of the inhomogeneity of the mineral distribution results in a large underestimation of the stresses and strains of possibly more than 50%. The stiffness of trabecular bone strongly influences the condylar deformation. Vice versa, the condylar deformation largely determines the magnitude of the strains in the trabecular bone.