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J Sciuk

Publications and source records attributed to J Sciuk.

At least 19 recordsLinked to original sources
PubMed2006

[Radioiodine therapy for combined disseminated and nodular thyroid autonomy. Results after using a correction term for the disseminated part].

AIM: In combined focal and disseminated thyroid autonomy a variety of concepts in the treatment with radioiodine are used. The difference lies mainly in the calculation of the autonomous volume. This retrospective study shows a new method of calculating the autonomous volume. PATIENTS AND METHODS: In 398 patients with combined thyroid autonomy and good correlation of scintigraphically hot nodules and lesions defined by ultrasound the volume of the nodules is ascertained from scintigraphic and ultrasound parameters and the volume of the disseminated autonomous tissue is assessed with a weighting factor (VF). This factor is the ratio of impulse density in a ROI over the disseminated volume divided by the corresponding impulse density over the nodular volume of the thyroid scintigraphy. The sum of nodular volume and weighted perinodular volume gives the total autonomous volume. A standard radioiodine test gives the maximum iodine-131-uptake and effective half-life to calculate the activity to obtain a treatment dose of 400 Gy. RESULTS: The rate of success with and without thyrostatic medication was 97% with an 18.6% rate of hypothyroidism observed from 4 months post therapy onwards. CONCLUSION: The use of the weighting factor VF in the treatment of combined autonomy leads to an excellent rate of success in patients with good correlation of functional imaging and ultrasound findings.

Humans↗
PubMed2004

Unilateral multicystic dysplastic kidney: experience in children.

OBJECTIVES: To report a retrospective study of unilateral multicystic dysplastic kidneys (MCDK) in children, assessing the contralateral kidneys and urinary tract, the functional consequences, and the urological and nephrological management and outcome, as unilateral MCDK is the most common cause of renal cystic disease in children, and malformations of the contralateral urinary tract and kidney (pelvi-ureteric obstruction, megaureter, reflux, renal dysplasia) have been reported. PATIENTS AND METHODS: The study included 97 patients (60 boys, 37 girls) with MCDK seen between 1985 and 1998; 82 were diagnosed in utero by ultrasonography (US). After birth, the diagnosis was verified by US, renal scanning (in 93) or intravenous urography (in four), and 89 (92%) had voiding cysto-urethrography (VCUG). Of the 97 children, 87 (90% had a mean (range) follow-up of 44.3 (15-115) months. RESULTS: The MCDK was removed in 17 children; the follow-up of 75 children (five lost to follow-up) showed total involution of the MCDK in 25%, shrinkage in 60% and a stable size in 15%. None had any sign of malignancy. The contralateral kidney showed anomalies in 19 of 97 children (20%); 12 had a dilated renal pelvis (two with megaureter), six had a high echogenicity of the contralateral kidney (one had reflux, and two also pelvic dilatation). In only four of the 89 children was reflux found by VCUG; 16 of the 19 anomalies were detected by US. Five children needed surgery on the contralateral urinary tract (three a pyeloplasty, and one each a pyeloplasty plus ureteroneocystostomy, and an antireflux procedure). Of the contralateral kidneys 43% showed compensatory hypertrophy. There was mild renal insufficiency in three children; renal function seemed to be slightly impaired in many. Five infants had hypertension (four with spontaneous resolution) caused by renal scarring after pyelonephritis or inborn dysplasia of the contralateral kidney. There were symptomatic urinary tract infections in seven children. CONCLUSION: US can be used safely to diagnose unilateral MCDKs and malformations of the contralateral urinary tract and kidney. In cases where US of the dysplastic kidney remains uncertain renal scintigraphy is necessary to detect the lack of renal function. The low rate of reflux makes routine VCUG unnecessary if the contralateral upper urinary tract and kidney appear to be normal on US. Nephrectomy of the dysplastic kidney in typical cases is also unnecessary. A long-term nephro-urological follow-up of children with MCDK is recommended.

Child↗
PubMed2002

[Valence of F-18-FDG-PET in the diagnosis of malignant lymphoma].

PET enables tomographic imaging and quantification of molecular metabolism with high temporal and spatial resolution. For routine clinical questions in oncology F-18-labeled fluorodeoxyglucose is the tracer of choice. In malignant lymphoma staging, response control and follow-up studies are valid indications. The initial glucose-uptake and especially the response of metabolism to therapy are in correlation with the outcome of the disease. Complementary to conventional staging PET is able to detect further lymphnode manifestation or extranodal involvement that can result in up-staging. Down-staging is less frequent. In follow-up studies PET is valuable, to assess therapy response, to differentiate viability of lymphoma from fibrous remnants at end of therapy and to detect relapse at an early stadium. In this context it proves to be superior to conventional tomographic imaging. In individual cases relevant therapeutic consequences arise from the metabolic PET-informations. Whether in future PET will be able to partially replace conventional imaging and whether it withstands to cost/effectiveness analysis requires additional prospective studies.

Blood Glucose↗
PubMed2002

FDG-PET for detection of recurrences from malignant primary bone tumors: comparison with conventional imaging.

BACKGROUND: The aim of this study was to assess the diagnostic ability of positron emission tomography using 2-[fluorine-18]fluoro-2-deoxy-D-glucose (FDG-PET) in the detection of recurrences from malignant primary bone tumors compared with conventional imaging. PATIENTS AND METHODS: In 27 patients (6 osteosarcomas, 21 Ewing's sarcomas), 41 FDG-PET examinations performed for diagnosis or exclusion of recurrent disease were evaluated. Conventional imaging techniques consisted of magnetic resonance imaging of the primary tumor site, thoracic computed tomography, and Tc-99m methylene diphosphonate bone scintigraphy. The reference methods were the histopathological analysis and/or the clinical and imaging follow-up. RESULTS: In 25 examinations reference methods revealed 52 sites of recurrent disease (local n = 7; distant: osseous n = 22, pulmonary n = 13, soft tissue n = 10). On an examination-based analysis FDG-PET had a sensitivity of 0.96, a specificity of 0.81 and an accuracy of 0.90. Corresponding values for conventional imaging were 1.0, 0.56 and 0.82. CONCLUSIONS: The sensitivity, specificity and accuracy of FDG-PET in the detection of recurrences from osseous sarcomas are high. On an examination-based analysis, FDG-PET had a not significantly lower sensitivity in comparison with conventional imaging. However, FDG-PET showed a small advantage in the detection of osseous and soft-tissue recurrences compared with conventional imaging.

Adolescent↗
PubMed2001

Characterization of 3-[123I]iodo-L-alpha-methyl tyrosine ([123I]IMT) transport into human Ewing's sarcoma cells in vitro.

3-[(123)I]Iodo-L-alpha-methyl tyrosine ([(123)I]IMT) scintigraphy of extracranial malignant tumors has been described, but little is known about the transport systems involved in [(123)I]IMT uptake into extracranial tumor cells. Here, the precise kinetics of [(123)I]IMT transport into human Ewing's sarcoma cells (VH-64) was determined. The apparent Michaelis constant was of high affinity value (K(m)=41.7+/-3.9 microM) and maximum transport velocitiy amounted to V(max)=20.7+/-0.6 nmol x mg protein(-1) x 10 min(-1). Inhibition experiments revealed the predominance of [(123)I]IMT uptake via sodium-independent system L.

Biological Transport↗
PubMed2001

FDG-PET for detection of pulmonary metastases from malignant primary bone tumors: comparison with spiral CT.

BACKGROUND: The purpose was the comparison of positron emission tomography using F-18-fluorodeoxy-glucose (FDG-PET) and spiral thoracic CT to detect pulmonary metastases from malignant primary osseous tumors. PATIENTS AND METHODS: In 71 patients with histologically confirmed malignant primary bone tumors (32 osteosarcomas, 39 Ewing's sarcomas) 111 FDG-PET examinations were evaluated with regard to pulmonary/pleural metastases in comparison with spiral thoracic CT. Reference methods were the clinical follow-ups for 6-64 months (median 20 months) or a histopathologic analysis. RESULTS: In 16 patients (23%) reference methods revealed a pulmonary/pleural metastatic disease. FDG-PET had a sensitivity of 0.50, a specificity of 0.98, and an accuracy of 0.87 on a patient based analysis. Comparable values for spiral CT were 0.75, 1.00, and 0.94. It was shown that no patient who had a true positive FDG-PET had a false negative CT scan, nor was a pulmonary metastases detected earlier by FDG-PET than by spiral CT. CONCLUSIONS: There seems to be a superiority of spiral CT in the detection of pulmonary metastases from malignant primary bone tumors as compared with FDG-PET. Therefore, at present a negative FDG-PET cannot be recommended to exclude lung metastases. However, as specificity of FDG-PET is high, a positive FDG-PET result can be used to confirm abnormalities seen on thoracic CT scans as metastatic.

Adolescent↗
PubMed2001

18F-Fluorodeoxyglucose PET in a patient with primary small bowel lymphoma: the only sensitive method of imaging.

This report describes the case of a patient with primary small bowel lymphoma. Well-established methods of imaging did not give a hint on diagnosis. Increased 18F-fluorodeoxyglucose uptake was visualized on performance of positron emission tomography, corresponding with the intraoperatively found tumorous process. The present case points to a potential superiority of positron emission tomography in visualizing primary small bowel lymphoma.

Aged↗
PubMed2001

Whole-body MR imaging for detection of bone metastases in children and young adults: comparison with skeletal scintigraphy and FDG PET.

OBJECTIVE: The purpose of this study was to compare the diagnostic accuracy of whole-body MR imaging, skeletal scintigraphy, and 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) for the detection of bone metastases in children. SUBJECTS AND METHODS: Thirty-nine children and young adults who were 2--19 years old and who had Ewing's sarcoma, osteosarcoma, lymphoma, rhabdomyosarcoma, melanoma, and Langerhans' cell histiocytosis underwent whole-body spin-echo MR imaging, skeletal scintigraphy, and FDG PET for the initial staging of bone marrow metastases. The number and location of bone and bone marrow lesions diagnosed with each imaging modality were correlated with biopsy and clinical follow-up as the standard of reference. RESULTS: Twenty-one patients exhibited 51 bone metastases. Sensitivities for the detection of bone metastases were 90% for FDG PET, 82% for whole-body MR imaging, and 71% for skeletal scintigraphy; these data were significantly different (p < 0.05). False-negative lesions were different for the three imaging modalities, mainly depending on lesion location. Most false-positive lesions were diagnosed using FDG PET. CONCLUSION: Whole-body MR imaging has a higher sensitivity than skeletal scintigraphy for the detection of bone marrow metastases but a lower sensitivity than FDG PET.

Adolescent↗
PubMed2001

High-activity samarium-153-EDTMP therapy followed by autologous peripheral blood stem cell support in unresectable osteosarcoma.

PURPOSE: Despite highly efficacious chemotherapy, patients with osteosarcomas still have a poor prognosis if adequate surgical control cannot be obtained. These patients may benefit from therapy with radiolabeled phosphonates. PATIENTS AND METHODS: Six patients (three male, three female; seven to 41 years) with unresectable primary osteosarcoma (n = 3) or unresectable recurrent sites of osteosarcomas (n = 3) were treated with high-activity of Sm-153-EDTMP (150 MBq/kg BW). In all patients autologous peripheral blood stem cells had been collected before Sm-153-EDTMP therapy. RESULTS: No immediate adverse reactions were observed in the patients. In one patient bone pain increased during the first 48 hrs after therapy. Three patients received pain relief. Autologous peripheral blood stem cell reinfusion was performed on day +12 to +27 in all patients to overcome potentially irreversible damage to the hematopoietic stem cells. In three patient external radiotherapy of the primary tumor site was performed after Sm-153-EDTMP therapy and in two of them polychemotherapy was continued. Thirty-six months later one of these patients is still free of progression. Two further patients are still alive. However, they have developed new metastases. The three patients who had no accompanying external radiotherapy, all died of disease progression five to 20 months after therapy. CONCLUSION: These preliminary results show that high-dose Sm-153-EDTMP therapy is feasible and warrants further evaluation of efficacy. The combination with external radiation and polychemotherapy seems to be most promising. Although osteosarcoma is believed to be relatively radioresistant, the total focal dose achieved may delay local progression or even achieve permanent local tumor control in patients with surgically inaccessible primary or relapsing tumors.

Adolescent↗
PubMed2000

FDG-PET for detection of osseous metastases from malignant primary bone tumours: comparison with bone scintigraphy.

The purpose of this study was to compare positron emission tomography using fluorine-18 fluorodeoxyglucose (FDG-PET) and technetium-99m methylene diphosphonate (MDP) bone scintigraphy in the detection of osseous metastases from malignant primary osseous tumours. In 70 patients with histologically proven malignant primary bone tumours (32 osteosarcomas, 38 Ewing's sarcomas), 118 FDG-PET examinations were evaluated. FDG-PET scans were analysed with regard to osseous metastases in comparison with bone scintigraphy. The reference methods for both imaging modalities were histopathological analysis, morphological imaging [additional conventional radiography, computed tomography (CT) or magnetic resonance imaging (MRI)] and/or clinical follow-up over 6-64 months (median 20 months). In 21 examinations (18%) reference methods revealed 54 osseous metastases (49 from Ewing's sarcomas, five from osteosarcomas). FDG-PET had a sensitivity of 0.90, a specificity of 0.96 and an accuracy of 0.95 on an examination-based analysis. Comparable values for bone scintigraphy were 0.71, 0.92 and 0.88. On a lesion-based analysis the sensitivity of FDG-PET and bone scintigraphy was 0.80 and 0.72, respectively. Analysing only Ewing's sarcoma patients, the sensitivity, specificity and accuracy of FDG-PET and bone scan were 1.00, 0.96 and 0.97 and 0.68, 0.87 and 0.82, respectively (examination-based analysis). None of the five osseous metastases from osteosarcoma were detected by FDG-PET, but all of them were true-positive using bone scintigraphy. In conclusion, the sensitivity, specificity and accuracy of FDG-PET in the detection of osseous metastases from Ewing's sarcomas are superior to those of bone scintigraphy. However, in the detection of osseous metastases from osteosarcoma, FDG-PET seems to be less sensitive than bone scintigraphy.

Adolescent↗
PubMed2000

Evaluation of chemotherapy response in primary bone tumors with F-18 FDG positron emission tomography compared with histologically assessed tumor necrosis.

PURPOSE: The purpose of this study was to evaluate the potential of positron emission tomography using F-18-fluoro-2-deoxy-D-glucose (FDG PET) to assess the chemotherapy response of primary osseous tumors compared with the degree of necrosis determined histologically. PATIENTS AND METHODS: Seventeen patients with primary bone tumors (11 osteosarcomas, 6 Ewing's sarcomas) were examined using FDG PET and planar bone scintigraphy before neoadjuvant chemotherapy and before surgery. Tumor response was classified histologically according to Salzer-Kuntschik (grades I-II: good response; grades IV-VI: poor response). In both imaging methods, quantification was performed using tumor to nontumor ratios (T:NT). RESULTS: Histologically, 15 patients were classified as having good responses (grade I, n = 1; grade II, n = 6; grade III, n = 8) and two as having poor responses (grades IV and V). FDG PET showed more than a 30% decrease in T:NT ratios in all patients who had good responses. However, three of these patients had increasing bone scintigraphy T:NT ratios, and another five had decreasing ratios of less than 30%. The patients with poor responses had increasing T:NT ratios and decreasing ratios of less than 30%, respectively, using both imaging methods. CONCLUSIONS: FDG PET seems to be a promising tool for evaluating the response of primary osseous tumors to chemotherapy. In this preliminary study, FDG PET was superior to planar bone scintigraphy.

Adolescent↗
PubMed1999

Reconstructive treatment of sclerosing osteomyelitis of the entire femur of 30 years' duration with avoidance of segmental resection.

We describe the successful operative treatment of a patient with chronic sclerosing osteomyelitis of the femur in which en bloc resection was avoided. Therapy consisted of combined endoscopic, computed tomography and bone scan-guided fenestration and intramedullary reaming, with removal of all sclerotic zones and normalization of the cortical thickness. An adequate supply of oxygen to the area was ensured by improved vascularisation and the application of hydrogen peroxide. At the medium term follow-up no recurrence was seen, and hip and knee function was normal.

Bone Cements↗
PubMed1999

Determination of extent and activity with radionuclide imaging in Erdheim-Chester disease.

Erdheim-Chester disease usually involves the diaphyseal and metaphyseal regions of tubular bones and various visceral organs. A 56-year-old woman presented with the histologically confirmed diagnosis of Erdheim-Chester disease. A Tc-99m MDP bone scan revealed the entire extent of the skeletal disease and showed unusual involvement of the epiphyses and axial skeleton. In addition to MRI, a Ga-67 citrate scan including SPECT showed extensive soft-tissue infiltration of different organs. Both Tc-99m MDP and Ga-67 scintigraphy are useful tools in determining the distribution of this rare disease.

Biopsy↗
PubMed1999

High-activity samarium-153-EDTMP therapy in unresectable osteosarcoma.

Despite highly efficacious chemotherapy, patients with osteosarcomas still have a poor prognosis if adequate surgical control cannot be obtained. We applied high-activity Sm-153-EDTMP therapy within a multimodal therapy concept to improve local control of an unresectable osteosarcoma with poor response to initial polychemotherapy. A 21-year-old woman with an extended, unresectable pelvic osteosarcoma and multiple pulmonary metastases was treated with high-activity of Sm-153- EDTMP (150 MBq/kg BW, total 8.1 GBq). Afterwards external radiotherapy of the primary tumor site was performed and polychemotherapy was continued, followed by autologous peripheral blood stem cell reinfusion. Within 48 h after Sm-153-EDTMP application the patient had complete pain relief. After three weeks the response was documented by 3-phase Tc-99m-MDP bone scintigraphy (primary tumor and metastases: decreased tracer uptake), whole-body F-18-FDG-PET (primary tumor and metastases: diminution of glucose metabolism) and thoracic CT (metastases: reduction of size). The present case warrants further evaluation of feasibility and efficacy of this multimodal therapy combination of high-activity Sm-153-EDTMP therapy, external radiation, polychemotherapy and stem cell support for unresectable osteosarcomas.

Adult↗
PubMed1998

[Role of 18F-FDG positron emission tomography in surgical evaluation].

Positron emission tomography (PET) using F-18-fluorine-deoxy-glucose (FDG) as a metabolic marker is a non-invasive diagnostic tool that can distinguish malignant processes from normal tissue by means of increased glycolysis. Since the advent of whole-body scanning, its higher spatial resolution compared with conventional scintigraphic methods leads to widespread applications of FDG-PET in oncology. The clinical value of FDG-PET has been proven for a number of tumor entities. As will be shown in the following review for bronchial, colorectal and pancreatic malignomas, functional imaging with FDG-PET provides relevant diagnostic information complementary to morphologic imaging.

Carcinoma, Bronchogenic↗